Global Warming
                created 7/06
                       updated 3/13/13

My technical essay on Global Warming is here:  Global Warming Physics
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'Unburnable carbon' perspective

Political nonsense
        The current political discussion of global warming has an amazing air of unreality.  Future warming (after a delay caused by the oceans) depends mainly on the level of CO2 in the atmosphere. Annual CO2 production from fossil fuels causes a (small, about 0.44%/year or 1.7 ppm) change (1st derivative) of atmospheric CO2 levels. Yet, unbelievably the political debate is about rates of increase/decrease in annual CO2 production rates, like whether annual production should be allowed to increase 10% or 30% in coming years. This is a debate about the rate of change of the rate of change (2nd derivative!) of atmospheric CO2 levels! This is a joke.

        Until the political global warming debate focuses (directly) on the CO2 levels in the atmosphere you know nothing serious is going to be done by the political classes.

Here's a Crock
       "Here is the good news: the bold steps that are needed to solve the climate crisis are exactly the same steps that ought to be taken in order to solve the economic crisis and the energy security crisis."  Al Gore in a NYT Op Ed, Nov 9, 2008  (Oh, and Gore has now taken to calling CO2 "pollution.")

Crock #2
        George Bush in 1999 campaigned in favor of regulating CO2 levels under the Clean Air act. A few months into office he says he's reversed his position and is not going to regulate CO2. Why? Because he received "new information". And what is this new information? A report from the Energy dept saying regulating CO2 would impose costs on coal burners and raise the price of electricity. What a crock! The politicians are (supposedly) in favor of  regulating CO2 emissions until someone tells them it will cost something! (from Hansen's new climate book)

Wow -- Carbon taxes
        Wait until governments start imposing carbon taxes. They will soon figure out that not only does it feel good to 'save the planet', but they will realized it's a great revenue stream, and they will want more and more (carbon) tax money.

What about earth's store of minerals and energy?

        Global warming is (from a wide perspective) a generational issue. Don't the present generations on earth have a moral responsibility to future earth generations to leave them an earth that is not depleted, polluted, and degraded?  The political classes by arguing that we should do (something) to minimize future global warming seem to be saying that, yes, we do have an obligation to future generations. But there is something bizarre here.

Let me get this straight ! --- We should, says a growing political consensus, try to minimize earth's future heat pollution (global warming), but at the same time do absolutely nothing to curb, slow, or in any way alter the current strip mining of the earth for minerals and stored energy. (Maybe we should be organizing our dumps so they can be mined in the future for rare elements? Nah!)  This is totally bizarre, reflecting either nearly total ignorance or selfishness. Clearly for future generations earth's heat pollution is only part of a much larger problem.
Obama's big plan (1/1/09)
        As Obama is about to come into office, here is his plan for shifting the nation's electrical supply toward renewables. Unless congress makes a huge effort to support renewables, which includes completely rebuilding the nation's electrical grid, which at this time it shows absolutely no sign of doing, the target of reaching 25% renewables in 17 years is likely a pipe dream.

        But look carefully at this graph, the red section is nearly the same height in 2025 as it is now! Even if this massive effort to grow renewables to 25% in 2025 succeeds, it mostly just serves to accommodate the expected growth in electrical demand. There is barely any reduction in fossil fuel usage. All the political talk about reducing carbon emissions with renewables is now seen to be nothing but hot air.

Obama/Democrats targets for renewables for next 17 years
(Technology Review magazine, Jan 2009)

My posting to NYT Global Warming article (1/18/11)
#28 (recommended by 4 readers)

        The article says, "US and the rest of the industrial world have not stopped the rise in their own output”, meaning the rise in CO2 emissions per year.

        There's a subtle trap here. It is the confusing of CO2 'levels' in the atmosphere with 'emissions', or how much the atmospheric CO2 levels change per year. It is the level of CO2 in the atmosphere, not its rate of change, that is the root problem and that is where the focus should be. I suspect many people, including unfortunately many politicians (nearly all of whom are technically untrained), do not understand that solving the global warming problem is much, much more difficult than just limiting the rise in emissions.

        Even if the rise in emissions were to be reduced to zero (or reduced 10-20%), it accomplishes virtually nothing. With emissions flat the CO2 level in the atmosphere will still climb every year by almost 2 ppm and will continue to climb year after year until basically we burn up all the fossil fuels we can get our hands on.

        The only way to prevent the earth from eventually returning to sea levels of the past, which puts most coastal cities underwater, is to directly pull CO2 from the atmosphere or make a drastic reductions (> 50%) in CO2 emissions.

Rep. Dana Rohrabacher (R -CA) on global warming --- What a yahoo! (12/8/09)
        I listened to nearly a nearly one hour speech (special orders House speech) by long time house member Dana Rohrabacher (R-CA) on CSpan about global warming. What a yahoo he is. From a political perspective he is a conservative global warming skeptic. His official bio says he is, "senior member on the House Committee on Science", yet he has no scientific training. His degrees are in history and American Studies (at least he's not a lawyer!).

        He (mano a mano) challenged anyone in the House to "debate" him on global warming. He called for an "honest debate" on global warming. Much of the speech was about the ten year old emails (Climategate) hacked from climate scientists and here he made some valid points, then he gets to the science. OK he says I'll address the issues raised by the other side. Let's take an "honest look", "let's answer it", he says, at the argument about how man made increases in CO2 are causing global warming. (I took notes)

         He says you know a lot of people think CO2 is a huge part of the atmosphere. On man told him 40% another 60%, but he then reveals the truth that CO2 is a "minuscule part of the atmosphere". It's ? 0.04% he says! Not only that but 70% of the 0.04% is due to natural sources! Wow!  He goes on like this for maybe ten minutes on this totally irrelevant point! This is how he addresses one of the key pieces of data underlying the concern with man made increases in CO2 after calling for an "honest debate". What an ignoramus or hatchet man!
        I'd be willing to bet that Rohrabacher is so technically ignorant (i.e. such a hack) that he has no idea how totally crazy he sounds when he goes on and on about the completely irrelevant fact that CO2 is only a tiny is the fraction of the atmosphere (? 0.05%).
        Here's a link to the speech (on YouTube). Jump to Part 4 for the nonsense about CO2 levels and how man's contribution to CO2 is a "minor part of a minuscule part of the atmosphere"

   (part 4)  (271views)

        He did  mention (sort of as a throw away) that historically CO2 has lagged temperature rise, which is a good point, but I suspect he takes this as evidence that CO2 doesn't cause global warming. It's well understood in the climate community that CO2 is a (lagging) amplifier of other primary driving mechanisms, like the insolation changes in solar radiation due to the earth's orbit. I would bet that Rohrabacher doesn't have a clue about what an 'amplifier' mechanism is. The whole speech reads like a list of talking points someone gave him. He read the whole speech.

        A few minutes later he is rambling on about how "we were told cyclamates (sweetener) were dangerous", and how "cranberries supposedly caused cancer". This is in a speech about global warming! His not so subtle point being I guess, don't listen to those scientists look at how wrong scientists were before (on foods). This from a senior member of the science committee!

my screen capture of Rohrabacher on CSPAN giving his 'Climate gate' speech (12/8/09)

        Clicking 'Global Warming' on Rohrabacher's house site (below) brings up a wealth of climate skeptic links and text of a 25 page climate speech he gave in March 2010.


New Republic's Chait on global warming (6/26/10)
        According to the New Republic there appears to be other climate equivalents to Rohrabacher in the house and senate.

        "Anybody unfortunate enough to witness the blustering assaults on climate science by meatheads like James Inhofe or Joe Barton can easily grasp the pitfalls of allowing Congress to adjudicate science." (whoops, my brother tells me that Joe Barton is the only engineer in congress)

        I checked Barton's web site and three of his five points on climate control are the same idiot argument that Rohrabacher uses, which is that CO2 is a trace gas in the atmosphere. (This must be on Republican party talking point list.)

        Jonathan Chait, the editor of New Republic, goes on to give a sort of (too kind) 'explanation' of why politicians have done and continue to do nothing on global warming. He basically has given up on congress and recommends that CO2 control be handed over to a regulatory agency, similar to how control of the money supply that was once managed by congress at the beginning of the 20th century was given over to the Federal Reserve.
        "First, it’s a technical issue requiring specialized knowledge. (Anybody unfortunate enough to witness the blustering assaults on climate science by meatheads like James Inhofe or Joe Barton can easily grasp the pitfalls of allowing Congress to adjudicate science.) Second, the issue requires long time horizons. Congress is not designed to minimize the risks of catastrophes that might take place decades hence. Nor is it prone to consider the interests of potential future industries, like renewable energy, alongside existing ones. And third, the issue requires imposing short-term pain in order to avert long-term costs, a trade-off most pols are loath to make." (Jonathan Chait, New Republic, 6/10)
        A related argument put forward by a global warming writer is that the politial process, which is all about incremental 'fixes' and compromises, is just inappropriate for dealing with mother nature.

       My own (simplistic) view of congressmen is that basically they won't do anything that will cost them a vote. They put their own personal interests above the good of the country. They are mostly lawyers, so they find it easy to spout only arguments that are in their personal interest.

Are politicians really this ignorant?
        Dec 09 National Geographic magazine has a piece about an MIT prof (John Sterman) testing his Sloan business students on global warming. Most of them think:

        If the annual rise in CO2 emissions can be stopped then, the rise of CO2 in the atmosphere will be stopped.
        Sterman thinks this is commonly held view and common too among politicians. Are politicians really this dumb? My ans: Well they are lawyers!

        I suspect Sterman is right, that anyone who tries to follow this story only from the press will have no real understanding. A huge number of people probably do believe that stopping annual increases in CO2 emissions 'solves' the global warming. It actually explains 99% of the political effort, and why it's such a crock!  (The so-called Copenhagen Accord mumbles about scientists saying deep cuts in CO2 emission are needed, and then next paragraph talks about stopping rises in CO2 emissions.)

Easy way to figure time to 480 ppm
        The big Copenhagen climate summit (Dec 2009) result (Copenhagen Accord) targets a maximum rise in Earth's temperature of 2C above preindustrial levels, which (according to headlines) translates into a CO2 target level of 480 ppm.

CO2 rises 1.7 ppm per year
        Linearizing the last 15 rise of CO2 atmospheric CO2 levels from the Mauna Loa CO2 graph (below) I read:

                            1980                                333 ppm   (actual 340 ppm)
                            2010                                384 ppm
                                                            delta   51 ppm in 30 years  (1.70 ppm/year)

480 ppm CO2 target  --- math is simple
        Any engineering can figure in his head what needs to happen to level out CO2 at 480 ppm.

        First if CO2 emissions just stop rising and are held at current levels (so CO2 continues to rise at 1.7 ppm/yr), then 480 ppm is reached in [(480 ppm - 384 ppm)/1.70 ppm/yr] = 56 years, and temperature continues rising from there.

        To level out CO2 at 480 ppm think triangle. If man made CO2 emissions are linearly ramped down starting now to zero (ignoring CO2 sinks, which in long term are small), then then the time we have to do this is [2 x 56 years] = 112 years to transition totally away from fossil fuels,  to a totally non-carbon based energy environment. (One hidden assumption being that we don't do any geo-engineering to pull CO2 out of the atmosphere and bury it.) So if 480 ppm is the magic number (questionable), then our task for the earth can be simply summarized:

Solving Global Warming (480 ppm CO2 limit)
        Starting now reduce man made CO2 emission by 1%/year, reaching (near) zero CO2 emission in a century!
Accounting for ocean sink
        I am not sure there is a good number for the ocean CO2 sink (short term), but National Geographic has the oceans now absorbing 25% of the annual annual man-made CO2 into atomosphere: 2.3 billion tons of CO2 absorbed by oceans out of the 9.1 billion metric tons of CO2 man puts into atmosphere. Since it takes the ocean a century or so to turn over, in this time frame the ocean sink is probably approx constant.

        The above argument of 112 years 'ramp down time' to level out CO2 to 480 ppm are still valid if one just linearly ramps down the annual atmospheric CO2 delta (from +1.7 ppm/yr to 0 ppm/yr) rather than CO2 emissions. It's a CO2 ramp down to 25% of current levels (instead of zero).

350 ppm CO2 target
        Some scientists as of 2009 have begun to argue (based on paleoclimate data) that the target for CO2 in the atmosphere should be 350 ppm.

        "Any value for carbon dioxide (CO2) in the atmosphere greater than 350 parts per million is not compatible 'with the planet on which civilization developed and to which life on earth is adapted.'  That bottom line won’t change: above 350 and, sooner or later, the ice caps melt, sea levels rise, hydrological cycles are thrown off kilter, and so on." (James Hansen, Nasa, below Hansen's 2007? paper.)

        Of course since CO2 levels are already above 350 ppm (384 ppm 2010) that means the political effort to 'solve' the global warming problem by reducing CO2 emissions is nothing but a joke! The politicians response to the 350 ppm limit has been, of course, to just totally ignore it. (I didn't even see 350 ppm ever mentioned in press coverage of the Copenhagen climate summit.)    (For 350 ppm politics see

        A 350 ppm limit implies we must have geo-engineering to pull CO2 out of the atmosphere! Probably supplemented with CO2 reductions, not as a matter of first priority, but just to ease the geo-engineering task.

CO2 sink/source baseline
        National Geographic in Dec 09 shows a bathtub model of the CO2 in the atmosphere, the work of MIT professor  John Sterman.  CO2 is the water level in the bath tub and rising because the tap is running (man made CO2 annually dumped into atmosphere) and the drain is only partially open (CO2 sinks). This is a good model for visualizing CO2 levels and what needs to be done to CO2 flows (emissions) to control the CO2 level.

Carbon Bathtub model --- National Geographic (12/09)
source ---

Checking numbers
            The net CO2 into the atmosphere should be (I would think) pretty accurate since the atmosphere mass is known, CO2 level is known and CO2 annual ppm rise is known. Units: metric ton is 1,000 kg (= 1.1 US ton approx). CO2 by volume is 383 ppm ?=> 582 ppm by weight (Wikipedia. I think this just reflects the ratio of atomic weight of CO2 (about 44) to N2 (about 28) and O2 (about 32).

               Atmosphere mass (total)                                      5.15 x 10^18 kg   (my global warming physics essay)
               CO2 fraction (582 ppm by weight)                     0.0582%  (by weight)

Hence CO2 (kg) in atmosphere

                          0.582 x 10^-3 x 5.15 x 10^18 kg  = 3.00 x 10^15 kg
                                                                                            check --- 3.0 x 10^15 kg is Wikipedia value for CO2
                                                                                                                in atmosphere --- Carbon Dioxide

Annual increment in CO2 in atmosphere

               (1.7 ppm vol/383 ppm vol) x 3.00 x 10^15 kg =
                           0.4439 x 10^-2        x 3.00 x 10^15 kg = 1.33 x 10^13 kg
                                                                                              = 13.3 x 10^9  x 1,000 kg
                                                                                              = 13.3 billion metric tons   (CO2 annual increment)

        Wow, this is way off (x3.2 higher) from the bathtub above, which has the number at 4.1 billion metric tons! The explanation has to be that the bathtub figure above the tons are 'carbon' (not CO2). It is called the Carbon bath tub, but all the flows are labeled CO2. It is not clear).

Scaling CO2 by atomic weights to get annual increment of 'carbon' in atmosphere

                    [12/(12 + 32)] x 13.3 billion metric tons = 3.63 billion metric tons
                                                                                                           pretty close

It's within 12%, but still it seem to me it should have come out within 1%.

How much must CO2 levels be cut back to stop CO2 from rising?
        Anyway the big message of the Bathtub model is that to flatten out CO2 levels means cutting back CO2 (or carbon) emissions to the sink levels. Their raw sink number of 5 billion metric tons yields a cut back to [5/9.1] = 55% of current levels.  Since I have my doubts the 2.7 into soil and plants is really a sink (it may depend on your assumptions about forest lifetime), it could be emissions need to be cut back to [2.3/9.1] = 26% of current levels!

        To flatten CO2 in atmosphere: Cut back CO2 emissions to ( 26% to 55% ) of current levels

Historical perspective
        Paleoclimate records show the temperature over the last few million years has naturally varied in a big way  (an order of magnitude more than in the last 1,000 years) almost all the time. The last 10,000 years of relatively stability stands out in the record as a strange anomaly. 90% of the time in the last few million years it has been colder than today, so the overwhelming odds are that natural forces (long term) will act to lower temperatures. Clearly some global warming is desirable as insurance to prevent another ice age cycle. Even well known researchers like Hansen agree with this.

        So the issue (correctly framed) is not just that Global Warming is bad..... The issue is how much (man made) global warming is desirable. Yet strangely, I never see a global warming guy give a number, or even attempt an argument, for desirable temperature rise! Hansen only says the rise from added greenhouse gases will be "far more" than we need.

Recent Ice Age Cycles
        In the last few million years the earth has been repeatedly cycling in and out of ice ages.  The cycles are very regular each lasting about 100k years, so there has been maybe two dozen or so cycles in the last 2.4 million years. Only for the last four cycles do we good data (from ice cores). The graph below of temperature vs time shows the last four cycles, and as you can see the regularity of the cycle is striking. By geological standards 400k years is very short. The time it has taken for sea floor spreading from the mid-Atlantic ridge to push North America and Europe apart is about 200 million years, so 400k years ago the Atlantic was 99.8% as wide as it is today. The map of the planet 400k years ago was nearly identical to today. This is important because snow accumulation and ocean circulation patterns change hugely as plate tectonics moves continents around.

        Many people think of ice ages as brief cold periods in an otherwise warm earth, in fact it is the other way around. For 90% of each cycle much of the earth is cold and permanently covered with glaciers. Only for short inter-glacial periods of 10k to 12k years of each cycle is the earth warm and relatively ice free.

Variations of temperature, methane, and atmospheric carbon dioxide concentrations derived from air trapped within ice cores from Antarctica (adapted from Sowers and Bender, 1995; Blunier et al., 1997; Fischer et al., 1999; Petit 1999). (Megavolcano Mt Toba erupted 74k years ago. Is it visible?)
        It extremely important to understand that we are now in one of these brief inter-glacial periods between ice ages. We entered this inter-glacial warm period about 10k years ago (time from then to now called the Holocene). From the graph above it would appear likely that the earth is due for another cooling/ice age period pretty soon, however, recent longer ice cores and the study of earth orbital cycles seem to indicate that the warm inter-glacial period every four cycles (this one) may be longer than normal, up to 26k years. I think its fair to say that the coming of a new ice age would be the mother of all global crises!

        The fig below shows temperature variations going back about ten time longer (last 5.5 Myr) than the figure above. It shows the climate has oscillated dozens of cycles in the last few million years. The four ice age cycles that fill the figure above in the figure below are just the first four squashed cycles on the left. This temperature data is reconstructed from from oxygen isotope ratios (O18 to O16) in carbonates of foraminifera shells in ocean sediments.

Re: natural temperature variations -- It was warmer in the last interglacial period (Eemian) than it is now. This is stated in Houghton's book, and it can be seen on the figure above. The figure below shows that the temperature 3 to 5 million years ago was consistently warmer than the interglacial peaks, so it must also have been warmer then than it is now.

Footnote on temperature data --- The temperature data above is reconstructed from ice cores drilled in the Antarctica. Ice core temperatures, of course, are a record of temperature variation at the poles. Houghton in his book says that it is generally estimated that the variations in global average temperature (during the ice ages) are  about half of what is found in polar ice core data.

        On the other hand the data below is based on ocean sediments (where in the ocean I don't know).  I would expect that temperature record from buried shells, which of course reflects ocean temperatures, to closely track global average temperatures. Therefore I find it strange that the ice core and ocean sediment data both show a 10C peak-peak variation in temperature during the last four ice ages! Shouldn't the sediment data show about half the temperature variation of the ice core data?  Does the plotted ice core temperature data contain a hidden scale factor of 1/2 so that it reflects global average temperatures?  (unresolved)

Cause of ice age cycles
        The cause of ice age cycle temperature oscillations are thought to be 'beat' notes between the periods of earth's elliptical orbit and wobble in the inclination of the earth axis. This is known as the Milankovitch Theory. These variations don't have much effect on the total sunlight energy falling on earth, but they have a substantial effect of the split of energy between summer/winter in the northern polar regions. A strongly tipped axis with the earth nearest the sun in summer in the northern hemisphere means warmer artic summers and colder artic winters. Here's a figure showing the orbital and inclinational changes lined up with ice age cycles.

        Milankovitch found in his analysis that the key mechanism leading to ice ages was cool summers (in northern hemisphere). If (at high latitudes) the summer is not warm enough to melt away all the snow left from the previous winter, then a runaway starts (technically a strong positive feedback). First, the snow depth will rapidly build up to glacier depths because each year the snow depth grows by a delta. Second, with snow on the ground all year the albedo increases causing more cooling. Over time the ice sheets by making their own local (? global) cooling are able to 'walk' further and further south.

Milankovitch_Variations.png (Wikipedia)

Civilization Coincides with Inter-glacial
       It's very likely not a coincidence that the rise of civilization has occurred almost entirely within a warm inter-glacial period. The last 10k years  About 10k years ago when the earth last warmed and CO2 levels rose, in a few widely scattered places early farming and domestication of animals began and as farm technology improved it spread because it provided more food with less labor than hunting and gathering. With the energy surplus provided by farming and domestic animals cities became sustainable and the non-farmers were free to develop writing and the myriad of skills civilization needs.

CO2 in Atmosphere
       It's hard to see the short 10k inter-glacial periods in the graph above, but you can just about make out that during these time CO2 concentration based on gas trapped in ice cores was about 280 ppm. How does this agree with modern measured CO2 values? Pretty close. Below is the best data on CO2 in the atmosphere measured at the top of Mauna Loa in Hawaii.

CO2 ppm in atomosphere (by volume)
Change in recent years is +1.70 ppm/year
(51 ppm delta eq 1980 to 2010, 51 ppm/30 year = 1.70 ppm/yr)
383 ppm (by volume) => 582 ppm (by weight)

Hard evidence on how effective politicians really are!

        The upward trend in the data is (mostly) due to the burning of fossil fuels (coal, oil, and gas). Coal, oil, and gas are all hydro-carbons with coal having the most carbon, oil less, and gas the least. When fossil fuels are burned, all the the carbon they contain goes into the atmosphere in the form of CO2. This is 'extra' carbon into the atmosphere coming from deep in the earth where it has been locked up for millions of years.

        All the carbon in land plants has come from the atmosphere (as CO2), so when plants decay, or are eaten, or burned, the carbon they put back into the atmosphere is just equal to what they pulled out when they grew. The same is true of plants in the sea. Therefore, not to worry, from a global warming point of view, when you see satellite pictures of huge fires in the Amazon or Indonesia.

        CO2 levels in the atmosphere are known to have an effect on earth's average temperature. CO2 is a strong greenhouse gas, meaning its gas molecules absorb certain wavelengths of heat preventing them from radiating out into space. If you look far, far back in earth's history when the sun was 30% weaker than it is now (based on solar models), it was high levels of CO2 in earth's atmosphere that warmed the planet (a lot) making it habitable. For much of earth's history, i.e. over billions of years, the big pattern has been CO2 levels going down as the sun warmed.

Aside on methane --- Ice core data (above) shows methane's atmospheric concentration varies substantially during ice ages, closely tracking CO2 and temperature. The reason for this variation was (until recently) not well understood. The primary source of methane is thought to be archea, which are primitive baceteria-like microbes, living in a few oxygen poor environments like wet lands and the gut of ruminant animals and insects. However in early 2006 a paper in Nature disclosed that a new, significant source of methane had been discovered: living plants, mostly in tropical regions. The mechanism by which plants are able to produce methane is not known at this time. The expansion and contraction of tropical flora with temperature might very well explain the ice age methane variations.
        It is estimated that civilization has tripled the concentration of methane in the atmosphere, from 0.6 ppm to 2 ppm, due mostly to increases in rice farming, cattle, and termites. While methane at 2 ppm is only about 0.5% of CO2's concentration, methane is 23 times more potent (by weight) as a global warming gas than CO2, so methane's contribution to global warming is about 10% that of CO2.
Sea level rise
         One of the key concerns about a warmer earth is that it means higher sea levels. Sea level is expected to rise for two separate reasons: one, (existing) water in oceans (and lakes) will expand as it warms, and two, any melting of the glaciers on Greenland or Antarctic continents will release more water into the hydraulic system and most of it will end up in the oceans. But, as is usual with global warming, things are complex and not very well understood.

Sea level rise  --- water expansion
        Water is most dense at 3.98C. If you plot the volume of a mass (specific weight) of water vs temperature, you find volume falls as temperature falls with the slope gradually lessening and falling to zero at 3.98C, and at still lower temperatures the volume starts to increase. Even making the (wildly unrealistic) assumption that a 1C warmer earth means that the temperature vs depth profile just moves up 1C, figuring the expansion of the oceans means knowing how ocean temperatures around the globe vary with depth.

        Note that the water in the oceans that is now colder than 3.98C (39.2F) will contract if it is warmed a little.  Symmetrical temperature changes about 4C produces no net increase in volume. For example, any water warming from 0C to 1C shrinks just about enough to cancel the expansion of the same mass of water warming from 7C to 8C. Similarly 1C to 2C water shrinkage cancels expansion from 6C to 7C water.

        To get an estimate of sea level change due to temperature rise, here's the density of water vs temperature at 4C and 5C increments.

                           temp        water density (g/cm^3)   delta 5C
                            0C                0.999841
                            4C                0.999973
                            8C                0.999849
                            4C                0.999973
                            9C                0.999781                +0.0192 %
                          14C                0.999244                +0.0537 %
                          19C                0.998405                +0.0839 %
                          24C                0.997296                +0.1109%

        For a rough (order of magnitude) estimate of sea level rise due to water expansion, let's just take the average expansion for a 1C change between 4C and 9C (ocean is cold). From the data above this is 1/5 x +0.0192 %, which expressed as a fraction is 1/5 x 1.92 x 10^-4 = 3.84 x 10-5. I'll just guess the average ocean depth is 2 miles. If we view the water in the ocean sitting in a depression of fixed area, then the percent increase in ocean depth (sea level) is the same as the percent increase in density.

                Sea level change = 3.84 x 10-5 x (2 x 5,280 ft) x 12 in/ft
                                            = 3.84 x 10^-5 x (1.27 x 10^5 in)
                                             = 4.9 in/degree C

        Above data shows that warm water expands much more strongly than cold water. The average expansion from 19C to 25C (+0.1109%) is almost six times the average expansion from 4C to 9C (+0.0192 %), so temperature increases in only the upper, warmer levels of the ocean may be alone be able to increase sea level a few inches per degree C of rise.

        After doing the above ballpark estimate, I checked Houghton's book Global Warming. He gives the estimated sea level rise in the 20th Century due to water expansion as between (3.3 to 6.7 cm) x 1in/2.54 cm = 1.3 to 2.6 inches. Pretty close.

Sea level rise  --- glacier melting
        It is important to understand that melting of ice floating in water has zero effect on sea level. Ice bergs ride 90% below the surface. When an ice berg melts, all the water from the melted ice fits in the volume of the ice below the surface. The water from the ice above the surface fits into the volume made available as the ice below the surface converts to a smaller volume of water. Importantly this argument applies to huge  'ice shelfs' on the edge of glaciers in Antarctica and Greenland. Much of this ice is from glaciers that have pushed off shore and are now floating on the water.

        What is important to sea level rise is any reductions of glaciers on land, which mostly means the huge glaciers covering Greenland and Antarctica. However, glaciers are very poorly understood and cannot (currently) be modeled. See the article from the Washington Post July 07, Clues to Rising Seas Are Hidden in Polar Ice, which I have posted below. Houghton says the contribution to sea level rise in the 20th century due to glacier melt in Greenland and Antarctica is thought to be small (neglible).

Gaia Hypothesis
        Why long term CO2 levels in the atmosphere have dropped to neatly compensate for the sun's long term warming is an area of active research. James Lovelock in his Gaia hypothesis argues that life on earth is the controlling factor and evidence is building that he may be right. Plants take in CO2 and put out oxygen. One argument goes that inorganic processes like volcanos pump high levels of CO2 into the atmosphere producing strong warming. Near the temperature at which plants are happy they suck in lots of CO2, some of which gets sequestered, pulling the levels in the atmosphere down.

        One important carbon sequestering mechanism is thought to be due to algae phyto-plankton (single cell marine plants) that grow tiny 'shell like' structures of calcite, which is calcium carbonate. Phyto-plankton are thought to be the top producer of calcite in the ocean, and when they die some of the hard calcite can sink to the ocean bottom and get buried. Here is neat picture from Wikipedia of the calcite growth in the algae coccolithophore (micron = 0.001 mm).


        If plants grow very strongly, CO2 levels drop weakening the greenhouse effect thus cooling the earth. Too much cooling and plants die off allowing inorganic processes to build up CO2 levels again. In other words Gaia postulates that life is part of a negative feedback loop and has long regulated earth's temperature via some combination of changes in CO2 levels and changes in earth's reflectivity (albedo).

        Gaia is all very interesting, but as far as is known it is a long term effect which makes it totally irrelevant to global warming issues over the next few hundred years. However, earth's history strongly confirms that CO2 levels in the atmosphere are very important in raising a planets average (surface) temperature to a level higher than a baseline set by the sun and the distance of the planet from the sun. Venus and Mars, whose atmospheres' consist mostly of CO2, (96% Venus, 95% Mars) also demonstrate the heating power of CO2.

Response time of atmosphere and ocean
        Many physical processes have an exponential response time. The nature of this response is to start quickly changing linearly with time, and as the new steady state condition is approached slow down and settle in with a long tail.  The equation is y= (1 - e^-t/tau) where tau is the called the time constant.  Because of the slow tail settling into a new value it is might seem difficult to say how long it takes for an exponential system to respond. To get around this problem the convention (used by engineers) is to define the response time as tau. When t=tau, the equation simplifies to (1 - e^-1) or (1- 0.37) = 0.63. Therefore the time constant (tau) of an exponential process is the time when 63% of a change (from one level to another) has occurred.

            earth temp response to                             30 year ?   (surface layer of ocean)
            increased greenhouse gases                  100+  year   (deep ocean)

            absorption of CO2 by ocean water        100 year (aprox)

            methane atmospheric lifetime                 10 year
                 (methane reacts with  OH,
                   hydroxyl radical)

        CO2 dissolves in water and over time as the ocean currents circulate much of the CO2 in the atmosphere will be pulled from the atmosphere and dissolved in the ocean raising its CO2 level. This is a slow process because deep ocean waters circulate slowly. Methane in the atmosphere must constantly be replenished, because a methane molecule only lasts about 10 years in the atmosphere before reacting with a hydroxyl radical (OH), which is made by cosmic rays disassociating water vapor.

Good thing --- Matched time constants??
        Here's an idea I have never seen anyone comment on. It recently occurred to me that the (rough) match of the ocean temp time constant and the ocean CO2 removal time constant (both on the order 100 yr) may be a good thing, a fortuitous coincidence. Why? Consider

        On the one hand --- CO2 put into the atmosphere stays there about 100 years before being dissolved in the ocean. So every increment of CO2 we add to the atmosphere has (potentially) a 100 year to effect an earth's power imbalance and consequent temperature rise.

       On the other hand --- The temperature rise due to CO2 (? other greenhouse gases) is delayed about 100 years due to the thermal inertia of the ocean.

So just when CO2 begins to have its full effect on temperature, CO2 levels start to fall.

Ocean temperature rise
        Climate modelers believe that in the short term (? 100 years) the main mechanism slowing the warming of earth is the huge thermal capacity of oceans, i.e. the oceans are absorbing most of the earth's current power unbalance.

        However, a teeny (?) little problem is that confirming data that oceans are absorbing the calculated power (estimated by Hansen at 0.85 w/m2) is thin.  Recently a major published paper on ocean temperature changes (Lyman et al, Recent Cooling of the Upper Ocean, Geophysical Research Letters, May 2006) had to be withdrawn when it was found that (both!) of the new temperature sensors being used were in error. (You would think this would be an area of research that would be adequately funded, but based on this evidence that does not appear to be the case.)

        A co-author with Hansen has a global warming site (see below).  In 2005 he says measured ocean temp data, which he describes as very high quality?,  confirms the oceans are absorbing 0.6 w/w based on ocean temperature measurements (1993 to 2003).

So What's the Problem?
        (letter to Wall Street Journal 6/06) ---  "The most recent warming period (inter glacial) is now the longest recorded. No research has established that natural forces that affect global climate have either ceased to operate or have been altered significantly. If human activity has indeed brought the ice age(s) to an end, then the greatest catastrophe to present civilization will have been avoided."  No doubt this is true, some warming as insurance against another ice age is probably a good idea. Also the mixing with ocean water will eventually pull down atmosphere CO2 levels.  So what's the problem?

        Well it's heating of the earth looking out 30, 50, 100 years from  now and the effects this may have on crops, city water supplies, mountain top fauna, artic, flooding of low lying coastline areas, ocean acidification, and some local regions seeing such large changes (for example, too much or too little rain) that they cannot support the lives of huge numbers of people now living there. This may already have happened in the Sahel region of Aftica.

        CO2 dissolved in water forms an acid (carbonic acid). Over time as the oceans continue to pull CO2 from the atmosphere it's going to reduce the pH of the oceans making them less alkaline. The worry, and it's a big one, is that a lower pH will kill some microorganism and small ocean creatures by preventing them from growing shells. Shells, being calcium carbonate, need an alkaline ocean to form, and some types of shells need a higher pH than others. The risks, long term, are huge here because the marine food chain might possibly be disrupted. This area needs a lot of research. Because the time constant of atmosphere-to-ocean CO2 transfer is so slow, some amount of ocean acidification cannot be prevented, the higher levels of CO2 already in the air are going to slowly lower the ocean pH.

        Calcium carbonate does not build up on the ocean floor in water deeper than 4,500 meters (2.4 miles) according to a Univ of Texas professor. He says the reason is (probably) excess CO2 level in deep water dissolve the tiny shells from the algae and other small critters as it drift down from the surface. Read about it here

         In addition to quasi-predictable effects of temperature change (derived from computer climate models) there is some risk, and this is a big worry, that doubling or tripling CO2 levels with fossil fuel CO2 could have a big, surprise effect. Ice core data and man's history show that there have often been rapid, large changes in earth's average climate. The climate appears to respond non-linearly to disturbances and can be chaotic. For example, suppose the Gulf stream shut down. We know it has shut down during some ice age cycles. Since it brings about 30% of Europe's warmth,  a shut down could make much of Europe nearly uninhabitable (Note, some climate researchers dispute the importance of the gulf stream to the climate of Europe, saying England is warm partly because it is on the east side of an ocean in the same way Seattle is warmer than Siberia).

            Bottom line: Allowing CO2 levels in the atmosphere to increase 'too much' (whatever that means!) means risk, risk, risk.

Really simple, big picture
        From a medium term point of view, say next 50 to 500 years, the CO2 problem is really very simple. The problem is very constrained. When you dig up a fossil fuel and burn it, there are only two things you an do with the resultant CO2, either release it (into the air or water) or capture and store it. Therefore, there are only two ways to prevent all the CO2 now stored underground in gas, oil, and coal from going into the atmosphere/ocean systems.

            1)  Don't use up all the gas, oil, and coal.  Leave a lot of it right where it is,
            2) Sequester carbon, meaning capture CO2 and put it somewhere. The
                            straightforward implementation of sequester is capture the CO2
                            from fuel combustion and pump it underground. At least one new
                            coal plant will do this.

        Thinking in earth engineering terms another type of carbon sequester might (one day) be possible: pull CO2 directly from the air or water and sequester it. Perhaps new plants or microbes could be engineered that would convert a fraction of the carbon they pull from the air or water into something that would survive long term, something that doesn't readily decompose or can be eaten by another microbe. Now there's a challenge!

Hasn't the climate varied (a lot) in the last 1,000 years?
        Answer: yes! It is a well documented fact that the climate of earth, even in the relatively short period of the last 1,000 years, has been all over the place. From 1,000 AD to 1,300 AD there was the medieval warm period, when wine grapes where grown in England and Greenland was colonized. This was followed by a cold period known as the little ice age, which lasted until the middle of the 19th century. During this time the river Thames in London regularly froze and the colonizers of Greenland were killed off by the cold. A particularly cold period corresponded with an unusual solar event, an almost complete lack of sunspots for 70 years (1645 to 1715), known as the Maunder Minimum.

        A good record of solar activity for last 1,000 years or so is available from the carbon 14 record. Radioactive carbon 14 (5,700 year half life) is made in the upper atmosphere by the action of cosmic rays converting nitrogen atoms to carbon atoms; the carbon then getting taken up by plants (as CO2). The carbon 14 nuclear reaction is an interesting one: nitrogen 14 (most common isotope) picks up a thermal (slow) neutron, which is part of the cascade created by a cosmic ray, and even though nitrogen 15 is stable(!) somehow the activated nitrogen spits out a proton. Hence atomic number 7, nitrogen 14, is converted to atomic number 6, carbon 14, with no change in atomic weight.

        Here is the (qualitative) correlation between carbon 14 concentrations and earth's temperature for the last 1,000 years.

Is solar variation responsible for 'global warming'? --- An interesting new climate theory (2/07)
        Svensmark, a Danish scientist, in recent years has put forward a new idea on climate variations. His idea is that small changes in the sun may have more impact on the earth's climate and temperature than is usually thought. Most climate researchers, when considering the effect of the sun on the earth's temperature, have looked (quite reasonably) at only variations in the sun's total energy output. There is no doubt this is important, and there is some evidence that solar variations may have been responsible for the 'medieval warm period' and the 'little ice age' of the last 1,000 years.

        Svensmark's new idea is that variations in the solar wind are affecting the earth's cosmic ray flux, and changes in the cosmic ray flux in turn change the cloud cover of the earth, because cosmic rays act as a seed for cloud formation due to their ability to ionize air.  He has a new book coming out discussing this: The Chilling Stars: A New Theory of Climate Change.  (After I had written up Svensmark basic ideas, I found a reference to his new book in Drudge on 2/11/07)

        "The sun is a variable star". This are the opening words in a paper by climate researchers Marsh ? Svensmark (Danish Space Research Institute). They have an interesting theory that small variations in solar activity affect the cloud cover on earth and in this way can cause relatively large temperature changes in earth's temperature. Briefly, the sun's variation affects the strength of the solar wind, which affects the number of cosmic rays hitting earth, which affects the cloud cover, which affects the earth's temperature. There is no doubt that clouds are very important in the energy balance that controls earth's temperature, yet lack of data and understanding of clouds introduces a serious weakness in all computer climate models.

        A key piece of data about how important the extent of cloud cover (probably) is to climate was found following 9/11, when for a few days nearly all planes worldwide were were grounded. Apparently their wispy high altitude contrails have a measurable, and significant, temperature effect, probably by changing the albedo (reflectivity) of the earth.

        Here is more on the Marsh ? Svensmark's thesis:

                a) solar sun spot cycles affect the strength of the solar wind (charged particles) coming from the sun.
                b) the magnetic field of the solar wind serves to deflect some of the high speed cosmic rays (protons) coming from the galaxy back into space, so a stronger solar wind means fewer cosmic rays hit earth
                c) cosmic rays that hit earth are (mostly) traveling near the speed of light, so they create a cascade of particles that strongly ionizes the atmosphere (i.e. strip electrons off atoms in the atmosphere)
                d) ionized atoms in the atmosphere serve as the nucleus for the formation of cloud droplets.

        Hence the argument is less solar activity means weaker solar wind allowing more cosmic rays through to hit earth, so more clouds form making the earth more reflective and hence cooler. Obviously the obverse is true too, more solar activity leads to fewer clouds and a warming earth. Below is a plot galactic cosmic radiation hitting earth (GCR , upper two curves) vs sunspots (bottom).  Do you see a cycle and a correlation here?.

So all climate researches are convinced of global warming?
        Nope. Wikipedia keeps a list of climate researchers who are in some ways skeptics. Some look at the huge climate variations of just the last 1,000 year, (in this time geography has been constant), the causes of which are not well understood, and argue we cannot separate out man-made from natural variations. Many argue that the climate computer models just don't work well, saying there are fundamental mismatches between the models and data. For example, the models say surface warming and upper air warming should increase together, but while surface warming has increased in the the last 30 years, satellite detect no warming of the upper air. Others argue that the climate models are unable to reproduce the major climate variation of the last few hundred thousand years, which is the ice age cycles shown at the beginning of this essay.

        Reid A. Bryson,  prof emeritus of Univ Wisconsin, founder of their dept of Meterology, age 86, is a skeptic. Excellent credentials: He has authored five books and more than 230 other publications and was identified by the British Institute of Geographers as the most frequently cited climatologist in the world. “the father of the science of modern climatology.” (Dudge 5/5/07)  He believes the earth is warming, but its not caused by CO2, it's a natural variation. He makes following points:

            Historical records indicate that the Mediaeval warm period (1,000 to 1,300) was probably warmer than today. He references: Eric the Red's navigattion instruction for sailing to Greenland (no ice problem, that came later). Greenland settlers homes are now covered by glaciers. When a glacier retreated in Alps, they found a silver mine under glacier. Earth has been warming from the Little ice age since 1800.

            First 30 feet of water vapor in atmosphere absorbes 80% of radiation from earth. CO2 absorbs 0.08% of the earth's radiation, 1,000 times less than water vapor!

Eemian temperature
        The last interglacial before the present interglacial (holocene) was about 130k years ago and is known as the Eemian. The Eemian is very interesting because (at its warmest) it was warmer by a few degrees C (about 3C) than now. And even more interesting there was less glaciation causing seas to be 3 to 5 meters (9 to 15 feet) higher than now. One piece of geological evidence confirming higher sea levels during the Eemian is that the Baltic sea expanded hugely, causing Scandinavia to become an island and putting much of north Europe under shallow water.

        The data below from Vostok (Antarctica) ice core data shows the temperature of the last two interglacials, Eemian and Holocene (ours), in considerable detail. The Eemian interglacial temperature has been moved forward in time (by about 130k years) and overlain with the Holocene interglacial temperature (by Staniford). Note how similar they are. The higher temperatures of the Eemian (for about 5k years) is clearly seen as the red bulge above the green in left center. Since both temperatures are from the same ice core and determined the same way, the relative difference between them is probably pretty accurate. (However, there's something strange about the shape of the green holocene curve. It doesn't match other Holocene curves in the 'corner' region 8k to 10k years ago. Other curves show the interglacial flat temperature extending back about 10k years.)

Eemian temp (red) superimposed on Holocene temp (green) -- Vostok ice core data (Stuart Staniford)

        Below is the full Vostok record of about 400k years showing four ice age cycles. This provides some context to the temperature data above. In the full Vostok record the Holocene and Eemian interglacial temperatures are the two, blue peaks on the left side.

400k years of Vostok ice core data  (Wikipedia)

Northern hemisphere glaciation and summer sun
        It is thought that ice age cycles are mostly due to variation in the pattern of sunlight hitting the earth due to perturbations in the earth's orbit (Milankovitch cycles). Curiously, in the context of the current global warming debate, the ice age driver is not the variation in the total sunlight hitting the earth, but a change in Northern Hemisphere summer sun (technically, a change in insolation -- INcoming SOLar radiATION). The change at 65 N latitude is quite substantial, about 20%, 440 to 540 w/m^2 over (roughly) 24k year cycle with the opposite change occurring in S latitudes).

       Locally glaciation growth is a run away condition. If just a tiny amount of winter's snow survives melting each summer, in almost no time (geologically speaking) a glacier appears, its growth reinforced by higher local albedo as the ice cover expands. Because the Northern Hemisphere has most of the land on the planet where glaciers can grow significantly, it is the amount of summer sun in the the Northern Hemisphere that to a large extent drives ice age cycles.

Glaciers and sea level
       I found an excellent global warming site (with lots of data) that has a good discussion of the Eemian and overview of new glacier data. The writer is Stuart Staniford, who describes himself as a software engineer and Phd in physics. (His publications are about software worms.) He points to a second site with an excellent set of slides (converted to .pdf) about Antarctica by Chris Rapley of the British Antarctic Survey. Staniford's essay is followed by dozens of posting on the Oil Drum site with comments on it.

        -- The summer sunlight is important because an ice sheet can only form in a place where it is cold enough in the summer that at least some of last winter's snow stays throughout the summer. As long as that is true, the ice sheet can build and build. If that is not true, it doesn't matter how much snow fell in the winter or how cold it is then -- the summer will reset the snow level to zero every year. So northern hemisphere sunlight basically controls the extent of the major ice sheets in a glaciation, which in turn control everything else (via albedo feedbacks and a not-fully settled feedback into the CO2 level). (Staniford)

Antarctic ice flow rates from satellite data
(Chris Rapley of British Antarctic Survey presentation as reprinted by Stuart Staniford)

         Antarctica is 99.7% ice covered and holds 90% of the world's glacier ice (2.2 km thick av). It has a total volume of  30 mil cubic km, which if it all melted would raise sea level by 57 meter (188 ft). Most of the remaining world's glacier ice (3 mil cubic km) is in the Greenland ice sheet. The 'sea level equivalent' locations of the Antarctica ice is broken out below:
                   ---  52 m in East Antarctica (2/3 of the continent) on bedrock (above sea level)
                   ---   5 m in West Antarctica (much below sea level)
                   ---  0.3 m in Antarctica peninsula (mountain chain)
                   ---  5.7 m Greenland

            IPCC in 2001 report had forecast Antarctica contributing negatively to sea level rise (more snow falls than ice is lost from edges.) But recent estimates (quoted by British Antarctic Survey) have Antarctica now making a small positive contribution (15% of present 0.2 m(8 in)/century rise). A 0.2C rise in ocean water around Antarctica has speeded melting at the edges causing the fast flowing ice flows 'rivers' (yellow, green) to speed up.

        -- It looks like the mass loss (of Antarctica's glaciers) is going (in the future) to be controlled by ocean temperatures. So the assessment is going to be about where and how much the ocean is going to warm off the coast of Antarctica, and how far inland the glaciers are going to speed up in response to the increased melting where they reach the ocean. This is going to have to be studied glacier by glacier all round the continent. (Staniford)

How much sea rise is in the 'pipeline'?
        Sea rise from glacier melt is a big, big worry long term (more than a century, probably). The Eemian data, to the extent it is understood, is very troubling. Eemian sea level 5 m higher than now must mean that in the Eemian the Antarctica and Greenland ice sheets melted back to a level about 8% smaller (in volume) than now {5m rise/(57 m Antarctica + 6 m Greenland) = 0.08}. Couple this with Eemain temperatures (from proxy sources) being a few degrees higher (3C) than now sustained for a few thousand years, and you get the following (steady state) relationship:

                        +3C higher Earth temp  => +15 ft higher sea level (due to glacier melt back)

        If, as Staniford argues, existing glacier melt in Antarctica is coming mostly from sea temperature rise, which occurs slowly, then we have more sea rise in the pipeline than it being figured by IPCC and others, who typically only look out a century or so. The current estimated earth temperature rise of 0.6C translates into a steady state sea level rise of about 0.6C/3C x 15 ft = 3 ft, and clearly CO2 levels are driving the earth's temperataure even higher!

        By driving Earth's temperature higher with increased CO2 from fossil fuel burning, are we not likely (long term > 100 yr) to see a fraction of the higher sea levels of the Eemian?  And doesn't the Eemain data, which need to be tightened, give us a real world scaling factor from temperature to sea level? It seems to me (? Staniford) that it probably does.
Hansen's new book (2009)
        I'm reading the new book of NASA's James Hansen's, one of the world's leading climate scientist --- Storms of My Grandchildren: The Truth About the Coming Climate Catastrophe and Our Last Chance to Save Humanity. The book relates the global warming politics he ran into under the Bush years and expands on his climate views that he presented a few years ago in a Scientific American article.

        He had been arguing the target should be 450 ppm (doubling from pre-industrial times), which was pretty mainstream. From levels of about 380 ppm another 70 ppm of CO2 rise could be accepted. He uses the same value I read of the Mona Loa curve (1.7 ppm rise/yr) at current emission levels. So to achieve the 450 ppm max his recommendations had been CO2 increases needed to soon flatted out (by about 2010) and begin a slow reduction to the CO2 sink level (whatever it is, maybe about half (?) current emission levels) by 2050. These are the terms in which politicians now at least 'talk'.

        But after studying paleoclimate data, Hansens views of allowable CO2 limits have recently changed. He made headlines when began arguing, as he does in the book, that CO2 limit needs to be 350 ppm, which of course is below the current level of about 383 ppm. This of course blows all the Copenhargen and IPCC goals of slowly decreasing emissions out of the water. The Obama administration who want to follow the science just (I think) ignored Hansen. In other words they did exactly as the Bush administration did when Hansen didn't say what they wanted to hear.

350 ppm argument
        Hansen points out that an MIT professor figured out 30 years ago what (an idealized) temperature change would be to a doubling of CO2 (from preindustrial levels) if changes were limited to only the atmosphere and ocean (no other feedbacks). With this limitation the answer found was a relatively small 1.2C. But Hansen says it is of course known the real temperature for a doubling of CO2 will be much larger because of feedbacks. This includes changes to atmospheric water vapor, clouds, plants, and albedo due to ice coverage. Global warming is all about understanding feedbacks he says. Some feedbacks are well understood, like H2O in atmosphere vs temperature,  and some not at all well understood, like albedo due to clouds. The real strength he argues of using paleoclimate data is that all feedbacks are included. We can get a 10 to 15% accurate scaling factor between watts/CO2 and temperature without a detail understanding of all feedbacks or how they interact.

        He argues (implicitly) that an earth out of power balance will (likely) have growing or declining ice sheet and hence changing sea levels, and sea levels change hugely during recent ice age cycles (100 meters). A Hansen key argument is a constant sea level for a millennium (1,000 years) or so indicates an earth in power balance.   So steady state scaling factors between CO2/forcing vs temperature can be pulled out of the paleoclimate date by comparing periods of constant sea level millennia: [last temperature minimum] to [our interglacial time (holocene)] which is about a 5C difference and [our holocene interglacial] to the [previous interglacial (emian)].

        The technical arguments are stated clearly, but scattered all around the book, so I have tried to pull them together to really see the argument. (Hansen's forcings are in w/m^2 avreraged 24 hr over whole earth, nominal 244w

        * Forcings are due to sun --- insulation and tiny watt changes. Insulation is northern hemisphere closer to sun in winter causes warmer winters (more snow) and cooler summers (increasing chances not all snow will melt) leading to growing larger northern hemisphere ice sheets and lower sea levels. In watts these changes are small (? 1 watt) bus sustained for a long time.

        * CO2 lags temperature change. CO2 changes do not 'cause' (originate) the temperature change. It is an amplifier (of solar forcings) and lags temperature changes. (I am confused here)

        * CO2 (methane, nitrous oxide) forcings in w/m can be calculed quite accurately (10 to 15%) from atmospheric physics.

        * Ice age minimum to maxmium (holecene) steady state millenia show a 5C (global average) change for 6.6 w of forcing for a scale factor of [5C/6.6w = 0.75C/w].

Atmospheric CO2 sink
        A puzzling (or poorly described) aspect of the CO2 emissions issue is the nature of the sink of CO2 from the atmosphere. When the measured CO2 increment of the atmosphere each year is compared against the annual CO2 dumped into the atmosphere by man (fossil fuels burning + cement + deforestation), it's found year after year that only about half (45% or 55%) remains in the atmosphere. There's a very fast sink for about half of the CO2 that's thought to be CO2 dissolving in the ocean and CO2 taken up by the earth.

        But what is the nature of this sink?  Presumably it's some sort of CO2 equilibrium rather than a fixed CO2 flow ('current source') type sink. One mechanism that seems reasonable (though I have nowhere seen this described) is that CO2 might come into equilibrium with surface ocean water, but then there would be a slow tail, which might be the set by CO2 diffusion in water, or more likely the time it takes ocean water to mix and overturn. Found no real info in Hansen's book, but in his target CO2 paper I found the curve below.

(update 5/9/12)
Hansen emphasizes the key climate risk in a new NYT OpEd

        Hansen in an oped piece in NYT argues the key point, which the technically ignorant lawyer-trained political class I am almost sure does not really understand. The point is digging up and burning huge amounts of new untraditional fossil fuels will drive CO2 levels above the level they were at in the last (of 40) climate cycles, and we know from the earth record that sea levels were hugely higher then and now. These higher sea levels would put nearly all coastal cities underwater! This is not a theoretical calculation, it is history.

        His points back to the Pliocene 2.5 million years ago. A check of Wikipedia shows this is prior to the Greenland ice sheet forming, and the reference is a 2008 article saying that sea levels were then 25 meters (83 ft) higher.

Game Over for the Climate
        By JAMES HANSEN, NYT OpEd, May 9, 2012

        GLOBAL warming isn’t a prediction. It is happening. That is why I was so troubled to read a recent interview with President Obama in Rolling Stone in which he said that Canada would exploit the oil in its vast tar sands reserves “regardless of what we do.”

         If Canada proceeds, and we do nothing, it will be game over for the climate. Canada’s tar sands, deposits of sand saturated with bitumen, contain twice the amount of carbon dioxide emitted by global oil use in our entire history. If we were to fully exploit this new oil source, and continue to burn our conventional oil, gas and coal supplies, concentrations of carbon dioxide in the atmosphere eventually would reach levels higher than in the Pliocene era, more than 2.5 million years ago, when sea level was at least 50 feet higher than it is now. That level of heat-trapping gases would assure that the disintegration of the ice sheets would accelerate out of control. Sea levels would rise and destroy coastal cities. Global temperatures would become intolerable. Twenty to 50 percent of the planet’s species would be driven to extinction. Civilization would be at risk.

         That is the long-term outlook. But near-term, things will be bad enough. Over the next several decades, the Western United States and the semi-arid region from North Dakota to Texas will develop semi-permanent drought, with rain, when it does come, occurring in extreme events with heavy flooding. Economic losses would be incalculable. More and more of the Midwest would be a dust bowl. California’s Central Valley could no longer be irrigated. Food prices would rise to unprecedented levels.

        If this sounds apocalyptic, it is. This is why we need to reduce emissions dramatically. President Obama has the power not only to deny tar sands oil additional access to Gulf Coast refining, which Canada desires in part for export markets, but also to encourage economic incentives to leave tar sands and other dirty fuels in the ground.

        The global warming signal is now louder than the noise of random weather, as I predicted would happen by now in the journal Science in 1981. Extremely hot summers have increased noticeably. We can say with high confidence that the recent heat waves in Texas and Russia, and the one in Europe in 2003, which killed tens of thousands, were not natural events — they were caused by human-induced climate change.

        We have known since the 1800s that carbon dioxide traps heat in the atmosphere. The right amount keeps the climate conducive to human life. But add too much, as we are doing now, and temperatures will inevitably rise too high. This is not the result of natural variability, as some argue. The earth is currently in the part of its long-term orbit cycle where temperatures would normally be cooling. But they are rising — and it’s because we are forcing them higher with fossil fuel emissions.

        The concentration of carbon dioxide in the atmosphere has risen from 280 parts per million to 393 p.p.m. over the last 150 years. The tar sands contain enough carbon — 240 gigatons — to add 120 p.p.m. Tar shale, a close cousin of tar sands found mainly in the United States, contains at least an additional 300 gigatons of carbon. If we turn to these dirtiest of fuels, instead of finding ways to phase out our addiction to fossil fuels, there is no hope of keeping carbon concentrations below 500 p.p.m. — a level that would, as earth’s history shows, leave our children a climate system that is out of their control.

        We need to start reducing emissions significantly, not create new ways to increase them. We should impose a gradually rising carbon fee, collected from fossil fuel companies, then distribute 100 percent of the collections to all Americans on a per-capita basis every month. The government would not get a penny. This market-based approach would stimulate innovation, jobs and economic growth, avoid enlarging government or having it pick winners or losers. Most Americans, except the heaviest energy users, would get more back than they paid in increased prices. Not only that, the reduction in oil use resulting from the carbon price would be nearly six times as great as the oil supply from the proposed pipeline from Canada, rendering the pipeline superfluous, according to economic models driven by a slowly rising carbon price.

        But instead of placing a rising fee on carbon emissions to make fossil fuels pay their true costs, leveling the energy playing field, the world’s governments are forcing the public to subsidize fossil fuels with hundreds of billions of dollars per year. This encourages a frantic stampede to extract every fossil fuel through mountaintop removal, longwall mining, hydraulic fracturing, tar sands and tar shale extraction, and deep ocean and Arctic drilling.

        President Obama speaks of a “planet in peril,” but he does not provide the leadership needed to change the world’s course. Our leaders must speak candidly to the public — which yearns for open, honest discussion — explaining that our continued technological leadership and economic well-being demand a reasoned change of our energy course. History has shown that the American public can rise to the challenge, but leadership is essential.

        The science of the situation is clear — it’s time for the politics to follow. This is a plan that can unify conservatives and liberals, environmentalists and business. Every major national science academy in the world has reported that global warming is real, caused mostly by humans, and requires urgent action. The cost of acting goes far higher the longer we wait — we can’t wait any longer to avoid the worst and be judged immoral by coming generations.

James Hansen directs the NASA Goddard Institute for Space Studies and is the author of “Storms of My Grandchildren.”
21 Century trends ? NASA's Aqua satellite
        (Not checked --- From an Australian source (Jennifer Marohasy) on Drudge that sound credible). She makes two points, which could be very important if she is right and the trends persist.

        --- Temperatures since 1998 have gone down and since 2002 have plateaued. She says the head of IPCC acknowledges this.

        --- NASA put up a satellite in 2002 called Aqua that monitors water in the atmosphere and clouds. She says the working assumption by climate modelers is that higher temperature allows the atmosphere to hold more water vapor (true), so that water vapor is an amplifier of CO2 induced temperature increases, in other words water vapor provides positive feedback. (Yup, Houghton's in his global warming book talks of water vapor being a multiplier).

        She says to everyone's surprise data from Aqua since 2002 is showing that the feedback is not positive it's negative. She says,

        "These findings actually aren't being disputed by the meteorological community. They're having trouble digesting the findings, they're acknowledging the findings, they're acknowledging that the data from NASA's Aqua satellite is not how the models predict."
 Random notes on carbon
        Wikipedia --  The carbon dioxide released (from volcanos) is roughly equal to the amount removed by silicate weathering; so the two processes, which are the chemical reverse of each other, sum to roughly zero, and do not affect the level of atmospheric carbon dioxide on time scales of less than about 100,000 yr.

        In addition to digging up buried carbon in the form of hydrocarbons, we are also digging up carbon in the form of carbonate rocks. About 5% of human related CO2 released into the atmosphere is from the production of cement, which involves crushing and baking carbonate rocks such as limestone and chalk. These rocks are also used in the production of iron and steel and other industrial processes.

        Many forms of sea life extract carbon and oxygen from seawater and combine them with calcium to produce calcium carbonate (CaCO3). This is used to produce shells and other hard body parts by a variety of organisms, such as coral, clams, oysters and some microscopic plants and animals. When these organisms die, their shells and body parts sink to the seabed.

        The carbon sequested in the ocean bottom in the form of carbonates is not permanently buried. Plate tectonics gradually moves sea floor and when an ocean plate collides with a continent it sinks (subducts) and melts freeing the carbon. The freed carbon is recycled into the atmosphere in the form of CO2 from the string of volcanoes that sit atop the world's subduction zones.

Ocean carbon sequester and replacement
        Found another reference that estimates that oceans remove from the atmosphere about 2% (6 bil tons/yr) of what photosynthesis removes. This reference also implied that most? of ocean absorbed carbon gets sequested to the ocean floor. I doubt this. However, some carbon must naturally get sequested, so to maintain steady state CO2 levels in the atmosphere there must be a natural source of carbon not from oxidation of biota. My guess is that this is primal carbon from deep in the crust, which takes the form of CO2 and CH4 (methane) that comes from volcanos and general outgassing.

New Coal Plants --- Big Problem
        (11/07 update) Good news --- China has started signing contracts with varius countries to build nuclear power plants and has announced that in the next 15-20 years they will probably build about 100 such plants.
        What is sometimes called the 'dirty little secret' of global warming is that a huge number of coal electrical power plants are planned to be built in the next 15 or so years, the equivalent of 700 1,000 megawatt plants. A large number of them in China. A Texas power company is planning to build 10 conventional (pulverized) coal plants in Texas very soon. According to Wall Street Journal their rational for building fast is to build the plants before carbon taxes come about expecting older plants will have their carbon emissions grandfathered in. A perverse incentive has come about. The possibility of coming cost penalties for carbon emissions is encouraging plants to get built now that have high emissions!

        Coal has the most carbon of all fossil fuels, so it has the highest CO2 output per BTU of energy. Burning coal now causes 37% of global CO2 emissions. Power plants have a 50 to 60 year lifetime, so if a huge number of new coal plants of the conventional type get built, the fight to control CO2 emissions in the 21st century is pretty much lost.

        According to an article in MIT's magazine coal plants need to be changed in two ways to dramatically reduce their CO2 emissions. One, build the type of coal burning plant where it is possible to capture CO2, and two, capture the CO2 and sequester it possibly by injecting it deep into the ground below the plant. Apparently with standard coal plants there is no known practical way to capture emitted CO2, probably because the concentration of CO2 in flue gases is low. But if coal is first gasified (partially burned) to 'syngas' (carbon monoxide and hydrogen), then it is possible, if somewhat expensive, to capture and sequester the carbon, and as a bonus easier to remove coal impurities like sulfur dioxide.

        American Electric Power is planning to build a large syngas plant (IGCC - Integrated Gasification Combined Cycle) in Great Bend OH. The technology for this is fairly mature. The plant will cost 15-20% more than a conventional coal plant, yet this plant does not do CO2 sequestration. CO2 sequestration for power plants, besides adding maybe 50% more to the cost of the plant, and underground sequestration not being possible at some sites due to the geology, is a technology still in development and thus full of risk.

        Power companies are not going to build more expensive coal plants for the 'good of the planet'. In most of the developed world a company has a duty to its shareholders to maximize return on capital. What is clearly needed to get existing coal technology used and to speed development of sequestration techniques is governmental action that applies a substantial 'cost' to CO2 emissions. Power companies then when working for their shareholders will have the right incentives to also help the planet by reducing CO2 emissions into the atmosphere.

Tom Friedman and Montana governor on coal
       "The bad news is that because of global warming -- fueled in part by carbon dioxide emissions from coal-burning electricity plants -- the only way we'll be able to use all those coal reserves is if we can burn coal without emitting the CO2. Otherwise we're cooked, literally." (Tom Friedman's column in NYT 1/10/07)

        In the same column Friedman discusses how Governor Schweitzer is working hard, and proposing good, detailed plans, on the coal-CO2 problem.  (Tom Friedman's column in NYT 1/10/07)

Interesting aside --- "Montana has one third of all the coal deposits in America -- 8 percent of all the coal in the world.  Montana's coal is roughly equivalent to 240 billion barrels of oil. That's enough to replace all our imported oil for 60 years,'' (Tom Friedman's column in NYT 1/10/07, quoting the governor of  Montana)
New York Times editorial on  ocean acidification
        The effect of CO2 on the oceans is finally making its way into the popular media. A Dec 24, 06 NYT editorial correctly emphasizes an obscure one sentence provision in the new fishing bill, Magnuson-Stevens Act, the basic law regulating fishing practices in American waters from 3 to 200 miles offshore. It directs Secretary of commerce to ask the National Research Council, part of the National Academy of Sciences to conduct a study of the acidification of the oceans and how this process affects the United States. It was inserted by Representative Jay Inslee, a Washington State Democrat.
         "Scientists are increasingly coming to believe that the carbon dioxide that humans are pumping into the air — the same carbon dioxide that is responsible for global warming — is also changing the chemistry of the oceans. Oceans act as a sink for carbon dioxide, absorbing it and then releasing it back into the atmosphere in roughly equal quantities. But as humanity has produced more and more carbon dioxide, the balance has been upset — the oceans, in effect, have had to absorb more carbon dioxide than they can handle. The result is acidification, a process that is already damaging tiny corals and that many scientists believe could ultimately wreak havoc on the delicate oceanic food chain."
New York Times 'Coal Plant' Editorial
        Several months after I wrote the above section on planned Chinese and American coal plants the New York Times fnally figured it out. Here is the NY Times editorial of Nov 25, 2006.
        "The front page of this newspaper’s business section recently featured two articles about the world’s most plentiful fuel, coal. Written from different parts of the globe, they framed the magnitude of the task confronting international negotiators and the newly empowered Democrats in Congress who want to put the brakes on emissions of carbon dioxide, the main global warming gas.
        One article pointed out that China will surpass the United States as the world’s largest emitter of carbon dioxide by 2009, a decade ahead of previous predictions. A big reason is the explosion in the number of automobiles, but the main reason is China’s ravenous appetite for coal, the dirtiest of all the fuels used to produce electricity. Already, China uses more coal than the United States, the European Union and Japan combined. Every week to 10 days, another coal-fired power plant opens somewhere in China, with enough capacity to serve all the households in Dallas or San Diego.
        What’s frightening about this for those worried about the long-term consequences of warming is that nearly all of these plants are being built along traditional lines, burning pulverized coal to make electricity. And what’s sad about it is that there’s a much cleaner coal-burning technology available. Known as I.G.C.C. — for integrated gasification combined cycle — this cleaner technology coverts coal into a gas before it is burned. These plants produce fewer of the pollutants that cause smog and acid rain than conventional power plants do. More important, from a global warming perspective, they also have the potential to capture and sequester greenhouse gases like carbon dioxide before they enter the atmosphere.
        This new technology is not readily available in China, but it is available to utilities in the United States. Which brings us to the second article — an announcement by TXU, a giant Texas energy company, that it intends to build 11 new coal-fired power plants in Texas, plus another dozen or so coal-fired monsters elsewhere in the country. All told, this would be the nation's largest single coal-oriented construction campaign in years.
        Is TXU availing itself of the cleaner technology? No. TXU will use the old pulverized coal model. The company says the older models are more reliable. But the real reason it likes the older models is that they are easier to build, cheaper to run and, ultimately, much more profitable. So, like the Chinese, TXU is locking itself (and the country) into at least 50 more years of the most
carbon-intensive technology around.
        Barbara Boxer, the California Democrat who will shortly assume command of the Senate environment committee, believes that we should impose a price on carbon emissions (as Europe has done) so that companies like TXU will begin to think about investing in cleaner technologies — technologies that China could then use in its power plants. The message from both Texas and China is that Ms. Boxer should get cracking."
Is the Antarctic Warming?
        In January 2002 a paper in Nature showed from 1966 to 2000  more of the Antarctic continent had cooled than had warmed. According to lead author of the paper (Peter Doran, University of Illinois at Chicago) in a NYT editorial (7/27/06) his Nature paper is being widely referenced by critics of global warming and misused. He says his studies offer "no evidence that the earth is cooling", and "Our study did find that 58 percent of Antarctica cooled from 1966 to 2000, but during that period, the rest of the continent was warming. And climate models created since our paper was published have suggested a link between the lack of significant warming in Antarctica and the ozone hole over that continent." In other words there may be a local effect due to changing ozone 'hole' above the continent.

        Doran concludes his editorial with, "In the meantime, I would like to remove my name from the list of scientists who dispute global warming. I know my coauthors would as well."

        My quick take on polar temperature studies is that while the Arctic clearly seems to be showing a warming trend, (as of now) this is not true in the Antarctic. It must be remembered that while from an astronomical point of view the earth's two polar regions are similar, from a geography point of view they are very different. The north polar region is an ocean; the south polar region is a large continent. There is no reason, apriori, for their climates to be similar.

Global Warming and US Congress
        Energy Subcommittee on Oversight ? Investigation had a hearing on global warming 7/27/06 shown on CSpan. There were 6 major experts on global warming (with different points of view) that gave extended testimony. The panel included Mann (of hockey stick fame), Wegman (hockey stick critic), and the president of  US Academy of Science. Graphs of isotope concentration and CO2 levels from ice core data covering 400k years ( like those included here) were shown and discussed.

        Several of the subcommittee members appeared to have a pretty good grasp of the science, however the Republican chairman was not among them. He was waving around the USA Today's temperature map for the previous day and complaining that none of the 'models' could reproduce it. One of the panel members tried to gently explain to him that climate and weather are not the same thing.

        Incredibly many members of the subcommittee couldn't be bothered to show up for the hearing!

Earth Engineering
        A totally different approach to global warming would be to figure out practical ways to modify the earth so we can nudge its average temperature down a little to fix global warming, or up a little if an ice age is upon us. Until very recently this has been considered dangerous and absurd. Almost nobody was working on the problem, almost no funding was available, and most scientific journals even refused to accept articles on this subject. Now after a decade of watching the politicians do almost nothing, things are beginning to change.

        Several Noble price winners have proposed ideas and ideas can now get published; many are featured in NYT or Wall St Journal, often on the front page. What is needed is money, lots of it. And the world is going to have to take some risks and spend some big bucks to let the scientist/engineers run some short term experiments. This is very important. No computer model can provide high confidence a scheme will work, the earth is too complex. Ideas must be tested, experiments must be run!

        In principle to adjust the earth's temperature you can either adjust the amount of heat being absorbed from the sun, or adjust the amount of absorbed heat that is radiated back out into space. Contrails from airplanes and sulfur particles thrown out by volcanos, by changing the albedo of the earth, affect the former. The greenhouse gases, by absorbing longer wavelength (heat) radiations from the earth, affect the latter.

        A few of the ideas proposed (remember work in this area has barely begun):
               put sulfur into tropical atmosphere
               put micromirrors in orbit around the earth
               fertilize the oceans with iron to support more plankton
               put highly reflective sulfate aerosols into the Arctic stratosphere (with guns or planes)
               froth the ocean surface to increase clouds

        A 25 million dollar prize is now being offered by (private citizen) Richard Branson for anyone who can figure out how to remove a billion tons of carbon dioxide per year from the atmosphere. The announcement of the prize was on the front page of the NYT 2/13/07 with Al Gore present saying it was an "important and welcome” initiative.

        This is part of a new Virgin Earth Challenge. "As far-fetched as it seems today, removing carbon dioxide from the atmosphere could turn out to be a lot more practical than the alternative: persuading six billion people to stop putting it there." (from the Branson press conference)

Interview with Craig Ventor (Dec 07)
        Craig Ventor, a big idea man who revolutionized the decoding and study of DNA, in an interview with Charlie Rose on TV had some interesting things to say about the possible role of biology in addressing the combo issue of  global warming ? energy. On global warming --- (adding huge amounts of carbon to atmosphere) is "playing a major crap shoot with our planet". On new sources of energy   -- "We need a thousand solutions for energy." Both of which are right on the mark.

        One of his (newer) companies is working to engineer new microbes. Craig thinks it's possible (or we need to find out) if microbes can for example:

            --- manufacture gasoline (some microbes naturally make some oily like products)
            --- take in CO2 (pulling it from atmosphere) and either help sequester it, or profitably use it
            --- make methane from coal. Instead of mining coal possibly we we could inject microbes
                            underground and extract the methane they make.

        Some other interesting thoughts he has: Biology is important to "help us survive (long term) on this planet". "The government (in funding technology) "is so risk adverse that they can't fund new ideas". His excellent example, was his own plans in the 90's for decoding the human genome --- He could get no government money for his approach until he proved it was feasible, and then he got more money than he could use. He said, "only DARPA internally (for defense department) does a good job developing new technology and taking the right amount of risk." "If a lot of their projects don't fail, then DARPA knows they are not taking enough risk." Yup.

Adaptation planning (2/07)
        Talk about adapting to global warming has (finally) started. Fareed Zakaria, in an excellent Newsweek column on global warming, first lays out the case that a lot of warming is bound to occur because of greenhouse gases already in the atmosphere and that India and China are planning to build 650 (conventional) coal fired plants (see Dirty Little Secret). He then describes a speech by the president of the British Association for the Advancement of Science who argues that (serious) planning for adaption for earth warming needs to begin.

        This could include new crop varieties of drought resistant crops and and restrictions on building on low lying land near the sea. Apparently nobody in New Orleans seems to be paying any attention to that one!  One huge advantage of adaption work is that it can move forward fast, since it can be done by individual countries or regions without (difficult to achieve) global coordination.
How to Cool a Planet (Maybe)
NY Times 6/27/06

        In the past few decades, a handful of scientists have come up with big, futuristic ways to fight global warming: Build sunshades in orbit to cool the planet. Tinker with clouds to make them reflect more sunlight back into space. Trick oceans into soaking up more heat-trapping greenhouse gases. Their proposals were relegated to the fringes of climate science. Few journals would publish them. Few government agencies would pay for feasibility studies. Environmentalists and mainstream scientists said the focus should be on reducing greenhouse gases and preventing global warming in the first place.

        But now, in a major reversal, some of the world's most prominent scientists say the proposals deserve a serious look because of growing concerns about global warming. Worried about a potential planetary crisis, these leaders are calling on governments and scientific groups to study exotic ways to reduce global warming, seeing them as possible fallback positions if the planet eventually needs a dose of emergency cooling. "We should treat these ideas like any other research and get into the mind-set of taking them seriously," said Ralph J. Cicerone, president of the National Academy of Sciences in Washington. The plans and proposed studies are part of a controversial field known as geoengineering, which means rearranging the earth's environment on a large scale to suit human needs and promote habitability. Dr. Cicerone, an atmospheric chemist, will detail his arguments in favor of geoengineering studies in the August issue of the journal Climatic Change.

        Practicing what he preaches, Dr. Cicerone is also encouraging leading scientists to join the geoengineering fray. In April, at his invitation, Roger P. Angel, a noted astronomer at the University of Arizona, spoke at the academy's annual meeting. Dr. Angel outlined a plan to put into orbit small lenses that would bend sunlight away from earth — trillions of lenses, he now calculates, each about two feet wide, extraordinarily thin and weighing little more than a butterfly. In addition, Dr. Cicerone recently joined a bitter dispute over whether a Nobel laureate's geoengineering ideas should be aired, and he helped get them accepted for publication. The laureate, Paul J. Crutzen of the Max Planck Institute for Chemistry in Germany, is a star of atmospheric science who won his Nobel in 1995 for showing how industrial gases damage the earth's ozone shield. His paper newly examines the risks and benefits of trying to cool the planet by injecting sulfur into the stratosphere. The paper "should not be taken as a license to go out and pollute," Dr. Cicerone said in an interview, emphasizing that most scientists thought curbing greenhouse gases should be the top priority. But he added, "In my opinion, he's written a brilliant paper."

        Geoengineering is no magic bullet, Dr. Cicerone said. But done correctly, he added, it will act like an insurance policy if the world one day faces a crisis of overheating, with repercussions like melting icecaps, droughts, famines, rising sea levels and coastal flooding. "A lot of us have been saying we don't like the idea" of geoengineering, he said. But he added, "We need to think about it" and learn, among other things, how to distinguish sound proposals from ones that are ineffectual or dangerous.

        Many scientists still deride geoengineering as an irresponsible dream with more risks and potential bad side effects than benefits; they call its extreme remedies a good reason to redouble efforts at reducing heat-trapping gases like carbon dioxide. And skeptics of human-induced global warming dismiss geoengineering as a costly effort to battle a mirage. Even so, many analysts say the prominence of its new advocates is giving the field greater visibility and credibility and adding to the likelihood that global leaders may one day consider taking such emergency steps. "People used to say, 'Shut up, the world isn't ready for this,' " said Wallace S. Broecker, a geoengineering pioneer at Columbia. "Maybe the world has changed." Michael C. MacCracken, chief scientist of the Climate Institute, a private research group in Washington, said he was resigned to the need to take geoengineering seriously. "It's really too bad," Dr. MacCracken said, "that the United States and the world cannot do much more so that it's not necessary to consider getting addicted to one of these approaches." Martin A. Apple, president of the Council of Scientific Society Presidents, said of geoengineering at a recent meeting in Washington, "Let's talk about research funding with enough zeroes on it so we can make a dent."

        The study of futuristic countermeasures began quietly in the 1960's, as scientists theorized that global warming caused by human-generated emissions might one day pose a serious threat. But little happened until the 1980's, when global temperatures started to rise. Some scientists noted that the earth reflected about 30 percent of incoming sunlight back into space and absorbed the rest. Slight increases of reflectivity, they reasoned, could easily counteract heat-trapping gases, thereby cooling the planet. Dr. Broecker of Columbia proposed doing so by lacing the stratosphere with tons of sulfur dioxide, as erupting volcanoes occasionally do. The injections, he calculated in the 80's, would require a fleet of hundreds of jumbo jets and, as a byproduct, would increase acid rain. By 1997, such futuristic visions found a prominent advocate in Edward Teller, a main inventor of the hydrogen bomb. "Injecting sunlight-scattering particles into the stratosphere appears to be a promising approach," Dr. Teller wrote in The Wall Street Journal. "Why not do that?"

        But government agencies usually balked at paying researchers to study such far-out ideas, and even ones that were more down to earth. John Latham, an atmospheric physicist at the National Center for Atmospheric Research in Colorado, told how he and his colleagues had unsuccessfully sought for many years to test whether spraying saltwater mists into low ocean clouds might increase their reflectivity. "We haven't found a way in," Dr. Latham said of government financing. "It's been a bit dispiriting." Other plans called for reflective films to be laid over deserts or white plastic islands to be floated on the world's oceans, both as ways to reflect more sunlight into space. Another idea was to fertilize the sea with iron, creating vast blooms of plants that would gulp down tons of carbon dioxide and, as the plants died, drag the carbon into the abyss. The general reaction to such ideas, said Alvia Gaskill, president of Environmental Reference Materials Inc., a consulting firm in North Carolina that advocates geoengineering, "has been dismissive and sometimes frightened — afraid that we don't know what the consequences will be of making large-scale changes to the environment." Dr. Gaskill said small experiments would let researchers quickly pull the plug if such tinkering started to go awry.

        Critics of geoengineering argued that it made more sense to avoid global warming than to gamble on risky fixes. They called for reducing energy use, developing alternative sources of power and curbing greenhouse gases. But international efforts like the Kyoto Protocol — which the United States never ratified, and which China and India as members of the developing world never had to obey, freeing the current and projected leaders in greenhouse gas emissions from its restrictions — have so far failed to diminish the threat. Scientists estimate that the earth's surface temperature this century may rise as much as 10 degrees Fahrenheit.

        Geoengineering's advocates say humankind is already vastly altering the global environment and simply needs to do so more intelligently. Dr. Angel, the University of Arizona astronomer, told members of the science academy of his idea for an orbital sunshade, calling the proposal less important than the goal of encouraging bold thought. "This could engage a whole generation," he said in an interview. "All I'm saying is, let's start thinking about these kinds of things in case we need them one day." Such visionary plans are still far from winning universal acclaim. James E. Hansen of the NASA Goddard Institute for Space Studies in New York, who attended the talk and strongly advocates curbing emissions, belittled the orbital sunshade as "incredibly difficult and impractical."

        Dr. Crutzen, the Nobel laureate from the Max Planck Institute, has also drawn fire for his paper about injecting sulfur into the stratosphere. "There was a passionate outcry by several prominent scientists claiming that it is irresponsible," recalled Mark G. Lawrence, an American scientist who is also at the institute. The stratospheric plan called for fighting one kind of pollution (excess greenhouse gases like carbon dioxide) with another (sulfur dioxide), though it appeared that any increase in sulfur at the earth's surface would be small compared with the tons already being emitted from the smokestacks of coal-fueled plants.

        Dr. Cicerone of the science academy helped broker a compromise: Dr. Crutzen's paper would be published, but with several commentaries, including his own. They will appear in the August issue of Climatic Change. The other authors are Dr. Lawrence of the German chemistry institute, Dr. MacCracken of the Climate Institute, Jeffrey T. Kiehl of the National Center for Atmospheric Research, and Lennart Bengtsson of the Max Planck Institute for Meteorology in Germany. In a draft of his paper, Dr. Crutzen estimates the annual cost of his sulfur proposal at up to $50 billion, or about 5 percent of the world's annual military spending. "Climatic engineering, such as presented here, is the only option available to rapidly reduce temperature rises" if international efforts fail to curb greenhouse gases, Dr. Crutzen wrote. "So far," he added, "there is little reason to be optimistic."
Colorado State professor disputes global warming is human-caused
(dissenting view on cause of global warming)

        Bill Gray, who has studied tropical meteorology for more than 40 years, is a professor at Colorado State University.  “I think we’re coming out of the little ice age, and warming is due to changes to ocean circulation patterns due to salinity variations,” Gray said.  And even if humans are causing global warming, there’s not much people can do, because China and India will continue to pump out greenhouse gases, and alternative energy sources are expensive.

        “Bill Gray is a widely respected senior scientist who has a view that is out of step with a lot of his colleagues’,” Pielke said. But challenging widely held views is “good for science because it forces people to make their case and advances understanding.”  Roger Pielke Jr., director of the Center for Science and Technology Policy Research at the University of Colorado, said in an interview later Monday that climate scientists involved with the Intergovernmental Panel on Climate Change concluded that most of the warming is due to human activity.
The End of Ingenuity (partial)
By Thomas Homer-Dixon
NYT Guest Editorial,  November 29, 2006

        A better measure of the cost of oil, or any energy source, is the amount of energy required to produce it. Just as we evaluate a financial investment by comparing the size of the return with the size of the original expenditure, we can evaluate any project that generates energy by dividing the amount of energy the project produces by the amount it consumes. Economists and physicists call this quantity the “energy return on investment” or E.R.O.I.

        For a modern coal mine, for instance, we divide the useful energy in the coal that the mine produces by the total of all the energy needed to dig the coal from the ground and prepare it for burning — including the energy in the diesel fuel that powers the jackhammers, shovels and off-road dump trucks, the energy in the electricity that runs the machines that crush and sort the coal, as well as all the energy needed to build and maintain these machines.

        As the average E.R.O.I. of an economy’s energy sources drops toward 1 to 1, an ever-larger fraction of the economy’s wealth must go to finding and producing energy. This means less wealth is left over for everything else that needs to be done, from building houses to moving around information to educating children. The energy return on investment for conventional oil, which provides about 40 percent of the world’s commercial energy and more than 95 percent of America’s transportation energy, has been falling for decades. The trend is most advanced in United States production, where petroleum resources have been exploited the longest and drillers have been forced to look for ever-smaller and ever-deeper pools of oil.

        Cutler Cleveland, an energy scientist at Boston University who helped developed the concept of E.R.O.I. two decades ago, calculates that from the early 1970s to today the return on investment of oil and natural gas extraction in the United States fell from about 25 to 1 to about 15 to 1.

        This basic trend can be seen around the globe with many energy sources. We’ve most likely already found and tapped the biggest, most accessible and highest-E.R.O.I. oil and gas fields, just as we’ve already exploited the best rivers for hydropower. Now, as we’re extracting new oil and gas in more extreme environments — in deep water far offshore, for example — and as we’re turning to energy alternatives like nuclear power and converting tar sands to gasoline, we’re spending steadily more energy to get energy.

        For example, the tar sands of Alberta, likely to be a prime energy source for the United States in the future, have an E.R.O.I. of around 4 to 1, because a huge amount of energy (mainly from natural gas) is needed to convert the sands’ raw bitumen into useable oil.

        Despite decades of increasingly dire warnings about the risks of dependence on foreign energy, the country now imports two-thirds of its oil; and during the last 20 years, despite increasingly clear scientific evidence regarding the dangers of climate change, the country’s output of carbon dioxide has increased by a fifth.

        Humankind’s energy and climate problems are intimately connected. Petroleum’s falling energy return on investment will encourage many economies to burn more coal (which in many parts of the world still has a relatively good E.R.O.I.), but coal emits far more greenhouse-inducing carbon dioxide. Perhaps the most urgent step, if humankind is going to return to coal as its major energy source, is to figure out ways of safely disposing of coal’s harmful carbon dioxide — probably underground.
Clues to Rising Seas Are Hidden in Polar Ice
By Juliet Eilperin,  Washington Post Staff Writer
July 16, 2007

        Few consequences of global warming pose as severe a threat to human society as sea-level rise. But scientists have yet to figure out how to predict it. And not knowing what to expect, policymakers and others are hamstrung in considering how to try to prevent it or prepare for it.

         To calculate sea-level rise, the key thing researchers need to understand is the behavior of the major ice sheets that cover Greenland and Antarctica. The disintegration of one would dramatically raise the ocean. But while computer models now yield an increasingly sophisticated understanding of how a warming atmosphere would behave, such models have yet to fully encapsulate the complex processes that regulate ice sheet behavior.

         "The question is: Can we predict sea level? And the answer is no," said David Holland, who directs New York University's Center for Atmosphere Ocean Science. Holland, an oceanographer, added that this may mean researchers will just have to watch the oceans to see what happens: "We may observe the change much more than we ever predict it."

         In its executive summary report for policymakers in February, the Intergovernmental Panel on Climate Change, composed of hundreds of leading climate scientists, barely hazarded a guess on sea level, predicting that it would rise between 7.8 inches and two feet by the end of the century. However, the United Nations-sponsored panel -- which operated under the assumption that, by 2100, the Greenland ice sheet would lose some mass but that the Antarctic ice sheet would gain some -- did not venture a best estimate or an upper limit for possible sea-level rise. The panel could agree to say only there is a 50-50 chance that a global temperature increase of between 1.8 and 7.2 degrees Fahrenheit would lead to a partial melting of the ice sheets over a period of several hundred to several thousand years.

        A three-foot increase in sea level could turn at least 60 million people into refugees, the World Bank estimates. Michael Oppenheimer, a Princeton University professor of geosciences and international affairs, does make a prediction: He figures that if the Greenland ice sheet disintegrates, sea level would rise about 23 feet. If the West Antarctic sheet melts, as well, it would add an additional 17 feet or so.

         "If either of these ice sheets were to disintegrate, it would destroy coastal civilization as we know it," Oppenheimer said.

         One of the biggest challenges facing researchers is that ice sheets are under "attack from the edges," in the words of Richard B. Alley, a Pennsylvania State University geosciences professor. Each sheet amounts to a pile of snow compressed over time into a two-mile thick, continent-spanning sheet of ice, which spreads out under its own weight, Alley said.

         Near the coast, the pile develops quick-moving "ice streams," which flow between slower-moving sections of ice and float out onto the ocean in an "ice shelf." While recent satellite data have indicated that these ice streams are flowing faster and delivering more water to the oceans, many uncertainties remain.

         David Vaughan, a glaciologist with the British Antarctic Survey in Cambridge, said the terrain beneath the ice streams helps determine how they move, but the contours of the land are largely unknown because it is buried so far under the ice. The streams may run aground on elevated bedrock, slow down as they move past rocky fjord walls or speed up as they move over mud. "There's a continent of topography sitting under Antarctica," Vaughn said. "Everything there has an impact on how the ice sheet flows, and very little of that has been mapped."

        Researchers are also trying to measure the layer of water that lies under the ice sheets, as that also helps regulate ice stream flows. "They're essentially afloat on their own sub-glacial water, even if there's not much water there," said Garry Clarke, a glaciology professor at the University of British Columbia. "We don't know very much about how water flows underneath ice sheets."

         Another uncertainty is how much the oceans surrounding the ice sheets are warming, something that is difficult to measure because the areas are remote. Vaughan and his colleagues suspect that warmer waters around Antarctica have contributed to melting the Western Antarctic ice sheet, but there is little good data because few ships venture there.

         Researchers are now going to extraordinary lengths to collect the data they need. Holland at NYU recently returned from a trip to Greenland, where he was collecting information about the Ilulissat glacier, which has doubled its speed over the past decade as it flows toward the ocean and melts. To test the temperature and salinity of the water surrounding the glacier, Holland and other researchers had to hover in a helicopter and lower their instruments into an opening in the ice.

         "It's kind of beautiful, and scary and fun," he said. Even with better data, scientists find it difficult to enter the information into computer models. Most models do not attempt to calculate what could happen to ice sheets at their edges. Adding to the challenge, Oppenheimer said, is that models "are only good at explaining things that happen at a large scale. Ice sheets are very complex beasts, and the water moves at a very small scale."

         Ice streams move along narrow channels, and plugging such detail into a computer model takes a long time. But without that level of detail, the results are incomplete. Researchers have made some progress in ice sheet science over the past decade by using satellites to measure the sheets' changing mass.

         Last month, for example, a team of NASA and university scientists used readings from NASA's QuikScat satellite to measure snow accumulation and melt in Antarctica from July 1999 through July 2005. They discovered that broad areas of snow had melted in west Antarctica in January 2005 in response to warmer temperatures. The finding was surprising because Antarctica had shown relatively little warming in the recent past.

         Konrad Steffen, director of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder, who led the study, said increases in snowmelt "definitely could have an impact on larger-scale melting of Antarctica's ice sheets if they were severe or sustained over time."

         Because ice sheet modeling has not ranked as a high priority for government laboratories and has not been integrated into large-scale climate models, scientists from around the world are now collaborating to develop more sophisticated models to inform policymakers about potential sea-level rise. The researchers have convened two major meetings this year, one at the NOAA Geophysical Fluid Dynamics Laboratory at Princeton University and one at the University of Texas at Austin, in an effort to generate a new generation of ice sheet models.

         Vaughan, who attended both conferences, said he is hopeful that he and others will solve the question of ice sheet modeling by the time he ends his career: "It will be 15 years before I retire, and I want it nailed by then."

         But other researchers are less optimistic. Holland, who like Vaughan is in his mid-40s, doubts that scientists will master the problem before greenhouse gas emissions trigger significant melting of the ice sheets that he studies. "We will get there eventually, but it won't be for a long time. It won't be in my lifetime," Holland said. "There's no plan; there's no program. There's no one responsible for sea-level rise."
(NYT op-ed that (probably) accurately points at ice-albedo feedback as being responsible for the large amount of open Artic ocean in late summer 2007 and a reason why the Artic seems to be warming more than the rest of the planet. This guy is not a scientist, but he seems to have the science right.)

A Swiftly Melting Planet
NYT Oct 4, 2007

        The Arctic ice cap melted this summer at a shocking pace, disappearing at a far higher rate than predicted by even the most pessimistic experts in global warming. But we shouldn’t be shocked, because scientists have long known that major features of earth’s interlinked climate system of air and water can change abruptly.

        A big reason such change happens is feedback — not the feedback that you’d like to give your boss, but the feedback that creates a vicious circle. This type of feedback in our global climate could determine humankind’s future prosperity and even survival.

        The vast expanse of ice floating on the surface of the Arctic Ocean always recedes in the summer, reaching its lowest point sometime in September. Every winter it expands again, as the long Arctic night descends and temperatures plummet. Each summer over the past six years, global warming has trimmed this ice’s total area a little more, and each winter the ice’s recovery has been a little less robust. These trends alarmed climate scientists, but most thought that sea ice wouldn’t disappear completely in the Arctic summer before 2040 at the earliest.

        But this past summer sent scientists scrambling to redo their estimates. Week by week, the National Snow and Ice Data Center in Boulder, Colo., reported the trend: from 2.23 million square miles of ice remaining on Aug. 8 to 1.6 million square miles on Sept. 16, an astonishing drop from the previous low of 2.05 million square miles, reached in 2005.

        The loss of Arctic sea ice won’t be the last abrupt change in earth’s climate, because of feedbacks. One of the climate’s most important destabilizing feedbacks involves Arctic ice. It works like this: our release of carbon dioxide and other greenhouse gases around the planet causes some initial warming that melts some ice. Melting ice leaves behind open ocean water that has a much lower reflectivity (or albedo) than that of ice. Open ocean water absorbs about 80 percent more solar radiation than sea ice does. And so as the sun warms the ocean, even more ice melts, in a vicious circle. This ice-albedo feedback is one of the main reasons warming is happening far faster in the high north, where there are vast stretches of sea ice, than anywhere else on Earth.

        There are other destabilizing feedbacks in the carbon cycle that involve the oceans. Each year, the oceans absorb about half the carbon dioxide that humans emit into the atmosphere. But as oceans warm, they will absorb less carbon dioxide, partly because the gas dissolves less readily in warmer water, and partly because warming will reduce the mixing between deep and surface waters that provides nutrients to plankton that absorb carbon dioxide. And when oceans take up less carbon dioxide, warming worsens.

        Global warming is melting large areas of permafrost in Alaska, Canada and Siberia. As it melts, the organic matter in the permafrost starts to rot, releasing carbon dioxide and methane (molecule for molecule, methane traps far more heat in the atmosphere than carbon dioxide).

        Warming is also affecting wetlands and forests around the world, helping to desiccate immense peat bogs in Indonesia, contributing to more frequent drought in the Amazon basin, and propelling a widening beetle infestation that’s killing enormous tracts of pine forest in Alaska and British Columbia. (This infestation is on the brink of crossing the Canadian Rockies into the boreal forest that extends east to Newfoundland.) Dried peat and dead and dying forests are vulnerable to wildfires that would emit huge quantities of carbon into the atmosphere.

        This summer’s loss of Arctic sea ice indicates that at least one major destabilizing feedback is gaining force quickly. Scientists have also recently learned that the Southern Ocean, which encircles Antarctica, appears to be absorbing less carbon, while Greenland’s ice sheet is melting at an accelerating rate.

        When warming becomes its own cause, we might not be able to stop extremely harmful climate change no matter how much we cut our greenhouse gas emissions. We need a far more aggressive global response to climate change. In the 1960s, mothers learned that the milk they were feeding their children was laced with radioactive material from atmospheric tests of nuclear weapons and that this contamination could increase the risk of childhood leukemia. Soon women organized themselves in the tens of thousands to demand that nuclear powers ban atmospheric testing. Their campaign largely succeeded.

        In response to the new dangers of climate change, we need a similar mobilization — of mothers, of students and of everyone with a stake in the future — now.

Thomas Homer-Dixon, a professor of peace and conflict studies at the University of Toronto, is the author of “The Upside of Down: Catastrophe, Creativity and the Renewal of Civilization.”
(A good,  comon sense global warming article by a Univ of Calif biologist. An article with a rational balance. And he makes an important point that exaggeration about the dangers of global warming is rife because many scientists think it is necessary to get politicans to do anything.)

Global Warming Delusions
The popular imagination has been captured by beliefs that have little scientific basis.

Sunday, October 21, 2007
Wall Street Journal

        Global warming doesn't matter except to the extent that it will affect life--ours and that of all living things on Earth. And contrary to the latest news, the evidence that global warming will have serious effects on life is thin. Most evidence suggests the contrary.

        Case in point: This year's United Nations report on climate change and other documents say that 20% to 30% of plant and animal species will be threatened with extinction in this century due to global warming--a truly terrifying thought. Yet, during the past 2.5 million years, a period that scientists now know experienced climatic changes as rapid and as warm as modern climatological models suggest will happen to us, almost none of the millions of species on Earth went extinct. The exceptions were about 20 species of large mammals (the famous megafauna of the last ice age--saber-tooth tigers, hairy mammoths and the like), which went extinct about 10,000 to 5,000 years ago at the end of the last ice age, and many dominant trees and shrubs of northwestern Europe. But elsewhere, including North America, few plant species went extinct, and few mammals.

        We're also warned that tropical diseases are going to spread, and that we can expect malaria and encephalitis epidemics. But scientific papers by Prof. Sarah Randolph of Oxford University show that temperature changes do not correlate well with changes in the distribution or frequency of these diseases; warming has not broadened their distribution and is highly unlikely to do so in the future, global warming or not.

        The key point here is that living things respond to many factors in addition to temperature and rainfall. In most cases, however, climate-modeling-based forecasts look primarily at temperature alone, or temperature and precipitation only. You might ask, "Isn't this enough to forecast changes in the distribution of species?" Ask a mockingbird. The New York Times recently published an answer to a query about why mockingbirds were becoming common in Manhattan. The expert answer was: food--an exotic plant species that mockingbirds like to eat had spread to New York City. It was this, not temperature or rainfall, the expert said, that caused the change in mockingbird geography.

        You might think I must be one of those know-nothing naysayers who believes global warming is a liberal plot. On the contrary, I am a biologist and ecologist who has worked on global warming, and been concerned about its effects, since 1968. I've developed the computer model of forest growth that has been used widely to forecast possible effects of global warming on life--I've used the model for that purpose myself, and to forecast likely effects on specific endangered species.

        I'm not a naysayer. I'm a scientist who believes in the scientific method and in what facts tell us. I have worked for 40 years to try to improve our environment and improve human life as well. I believe we can do this only from a basis in reality, and that is not what I see happening now. Instead, like fashions that took hold in the past and are eloquently analyzed in the classic 19th century book "Extraordinary Popular Delusions and the Madness of Crowds," the popular imagination today appears to have been captured by beliefs that have little scientific basis.

        Some colleagues who share some of my doubts argue that the only way to get our society to change is to frighten people with the possibility of a catastrophe, and that therefore it is all right and even necessary for scientists to exaggerate. They tell me that my belief in open and honest assessment is na?ve. "Wolves deceive their prey, don't they?" one said to me recently. Therefore, biologically, he said, we are justified in exaggerating to get society to change.

        The climate modelers who developed the computer programs that are being used to forecast climate change used to readily admit that the models were crude and not very realistic, but were the best that could be done with available computers and programming methods. They said our options were to either believe those crude models or believe the opinions of experienced, data-focused scientists. Having done a great deal of computer modeling myself, I appreciated their acknowledgment of the limits of their methods. But I hear no such statements today. Oddly, the forecasts of computer models have become our new reality, while facts such as the few extinctions of the past 2.5 million years are pushed aside, as if they were not our reality.

        A recent article in the well-respected journal American Scientist explained why the glacier on Mt. Kilimanjaro could not be melting from global warming. Simply from an intellectual point of view it was fascinating--especially the author's Sherlock Holmes approach to figuring out what was causing the glacier to melt. That it couldn't be global warming directly (i.e., the result of air around the glacier warming) was made clear by the fact that the air temperature at the altitude of the glacier is below freezing. This means that only direct radiant heat from sunlight could be warming and melting the glacier. The author also studied the shape of the glacier and deduced that its melting pattern was consistent with radiant heat but not air temperature. Although acknowledged by many scientists, the paper is scorned by the true believers in global warming.

        We are told that the melting of the arctic ice will be a disaster. But during the famous medieval warming period--A.D. 750 to 1230 or so--the Vikings found the warmer northern climate to their advantage. Emmanuel Le Roy Ladurie addressed this in his book "Times of Feast, Times of Famine: A History of Climate Since the Year 1000," perhaps the greatest book about climate change before the onset of modern concerns with global warming. He wrote that Erik the Red "took advantage of a sea relatively free of ice to sail due west from Iceland to reach Greenland. . . . Two and a half centuries later, at the height of the climatic and demographic fortunes of the northern settlers, a bishopric of Greenland was founded at Gardar in 1126."

        Ladurie pointed out that "it is reasonable to think of the Vikings as unconsciously taking advantage of this [referring to the warming of the Middle Ages] to colonize the most northern and inclement of their conquests, Iceland and Greenland." Good thing that Erik the Red didn't have Al Gore or his climatologists as his advisers.

        Should we therefore dismiss global warming? Of course not. But we should make a realistic assessment, as rationally as possible, about its cultural, economic and environmental effects. As Erik the Red might have told you, not everything due to a climatic warming is bad, nor is everything that is bad due to a climatic warming.

        We should approach the problem the way we decide whether to buy insurance and take precautions against other catastrophes--wildfires, hurricanes, earthquakes. And as I have written elsewhere, many of the actions we would take to reduce greenhouse-gas production and mitigate global-warming effects are beneficial anyway, most particularly a movement away from fossil fuels to alternative solar and wind energy.

        My concern is that we may be moving away from an irrational lack of concern about climate change to an equally irrational panic about it. Many of my colleagues ask, "What's the problem? Hasn't it been a good thing to raise public concern?" The problem is that in this panic we are going to spend our money unwisely, we will take actions that are counterproductive, and we will fail to do many of those things that will benefit the environment and ourselves.

        For example, right now the clearest threat to many species is habitat destruction. Take the orangutans, for instance, one of those charismatic species that people are often fascinated by and concerned about. They are endangered because of deforestation. In our fear of global warming, it would be sad if we fail to find funds to purchase those forests before they are destroyed, and thus let this species go extinct.

        At the heart of the matter is how much faith we decide to put in science--even how much faith scientists put in science. Our times have benefited from clear-thinking, science-based rationality. I hope this prevails as we try to deal with our changing climate.

Mr. Botkin, president of the Center for the Study of the Environment and professor emeritus in the Department of Ecology, Evolution, and Marine Biology at the University of California, Santa Barbara, is the author of "Discordant Harmonies: A New Ecology for the Twenty-First Century" (Replica Books, 2001).
Letter from 100 sceptical scientest presented to UN at Bali Climate Conference
Dec 2007
His Excellency
Ban Ki-MoonSecretary-General,
United Nations New York, N.Y.

Dear Mr. Secretary-General,

Re: UN climate conference taking the World in entirely the wrong direction

        "It is not possible to stop climate change, a natural phenomenon that has affected humanity through the ages. Geological, archaeological, oral and written histories all attest to the dramatic challenges posed to past societies from unanticipated changes in temperature, precipitation, winds and other climatic variables. We therefore need to equip nations to become resilient to the full range of these natural phenomena by promoting economic growth and wealth generation.

        The United Nations Intergovernmental Panel on Climate Change (IPCC) has issued increasingly alarming conclusions about the climatic influences of human-produced carbon dioxide (CO2), a non-polluting gas that is essential to plant photosynthesis. While we understand the evidence that has led them to view CO2 emissions as harmful, the IPCC's conclusions are quite inadequate as justification for implementing policies that will markedly diminish future prosperity. In particular, it is not established that it is possible to significantly alter global climate through cuts in human greenhouse gas emissions. On top of which, because attempts to cut emissions will slow development, the current UN approach of CO2 reduction is likely to increase human suffering from future climate change rather than to decrease it.

        The IPCC Summaries for Policy Makers are the most widely read IPCC reports amongst politicians and non-scientists and are the basis for most climate change policy formulation. Yet these Summaries are prepared by a relatively small core writing team with the final drafts approved line-by-line by government representatives. The great ?majority of IPCC contributors and reviewers, and the tens of thousands of other scientists who are qualified to comment on these matters, are not involved in the preparation of these documents. The summaries therefore cannot properly be represented as a consensus view among experts.

Contrary to the impression left by the IPCC Summary reports:

        * Recent observations of phenomena such as glacial retreats, sea-level rise and the migration of temperature-sensitive species are not evidence for abnormal climate change, for none of these changes has been shown to lie outside the bounds of known natural variability.

        * The average rate of warming of 0.1 to 0. 2 degrees Celsius per decade recorded by satellites during the late 20th century falls within known natural rates of warming and cooling over the last 10,000 years.

        * Leading scientists, including some senior IPCC representatives, acknowledge that today's computer models cannot predict climate. Consistent with this, and despite computer projections of temperature rises, there has been no net global warming since 1998. That the current temperature plateau follows a late 20th-century period of warming is consistent with the continuation today of natural multi-decadal or millennial climate cycling.

        In stark contrast to the often repeated assertion that the science of climate change is "settled," significant new peer-reviewed research has cast even more doubt on the hypothesis of dangerous human-caused global warming. But because IPCC working groups were generally instructed ( ) to consider work published only through May, 2005, these important findings are not included in their reports; i.e., the IPCC assessment reports are already materially outdated.

        The UN climate conference in Bali has been planned to take the world along a path of severe CO2 restrictions, ignoring the lessons apparent from the failure of the Kyoto Protocol, the chaotic nature of the European CO2 trading market, and the ineffectiveness of other costly initiatives to curb greenhouse gas emissions. Balanced cost/benefit analyses provide no support for the introduction of global measures to cap and reduce energy consumption for the purpose of restricting CO2 emissions. Furthermore, it is irrational to apply the "precautionary principle" because many scientists recognize that both climatic coolings and warmings are realistic possibilities over the medium-term future.

        The current UN focus on "fighting climate change," as illustrated in the Nov. 27 UN Development Programme's Human Development Report, is distracting governments from adapting to the threat of inevitable natural climate changes, whatever forms they may take. National and international planning for such changes is needed, with a focus on helping our most vulnerable citizens adapt to conditions that lie ahead. Attempts to prevent global climate change from occurring are ultimately futile, and constitute a tragic misallocation of resources that would be better spent on humanity's real and pressing problems."
Here is a new global warming web site tracking both pro/con.

        Interesting new (2007) book by a Danish economist (part of the Copenhagen Consensus) that compares the economics of CO2 reduction vs accommodation. He makes a convincing case that the return on money spent on CO2 reduction is tiny; that it is orders of magnitude better to invest in accommodation. He also shows that benefits of global warming are routinely ignored. For example, a warmer earth will causes more 'heat' deaths, but less cold mess fewer 'cold' deaths. He quotes studies that show on balance a warmer earth saves lives, many more people are not killed by cold than die of heat.

    Cool It: The Skeptical Environmentalist's Guide to Global Warming, by Bj?rn Lomborg

(Some common sense, and an interesting perspective on power, from Charles Krauthammer)

Carbon Chastity, The First Commandment of the Church of the Environment
        By Charles Krauthammer (May 30, 2008)

        I'm not a global warming believer. I'm not a global warming denier. I'm a global warming agnostic who believes instinctively that it can't be very good to pump lots of CO2into the atmosphere but is equally convinced that those who presume to know exactly where that leads are talking through their hats.

        Predictions of catastrophe depend on models. Models depend on assumptions about complex planetary systems -- from ocean currents to cloud formation -- that no one fully understands. Which is why the models are inherently flawed and forever changing. The doomsday scenarios posit a cascade of events, each with a certain probability. The multiple improbability of their simultaneous occurrence renders all such predictions entirely speculative.

        Yet on the basis of this speculation, environmental activists, attended by compliant scientists and opportunistic politicians, are advocating radical economic and social regulation. "The largest threat to freedom, democracy, the market economy and prosperity," warns Czech President Vaclav Klaus, "is no longer socialism. It is, instead, the ambitious, arrogant, unscrupulous ideology of environmentalism."

        If you doubt the arrogance, you haven't seen that Newsweek cover story that declared the global warming debate over. Consider: If Newton's laws of motion could, after 200 years of unfailing experimental and experiential confirmation, be overthrown, it requires religious fervor to believe that global warming -- infinitely more untested, complex and speculative -- is a closed issue.

        But declaring it closed has its rewards. It not only dismisses skeptics as the running dogs of reaction, i.e., of Exxon, Cheney and now Klaus. By fiat, it also hugely re-empowers the intellectual left.

        For a century, an ambitious, arrogant, unscrupulous knowledge class -- social planners, scientists, intellectuals, experts and their left-wing political allies -- arrogated to themselves the right to rule either in the name of the oppressed working class (communism) or, in its more benign form, by virtue of their superior expertise in achieving the highest social progress by means of state planning (socialism).

        Two decades ago, however, socialism and communism died rudely, then were buried forever by the empirical demonstration of the superiority of market capitalism everywhere from Thatcher's England to Deng's China, where just the partial abolition of socialism lifted more people out of poverty more rapidly than ever in human history.

        Just as the ash heap of history beckoned, the intellectual left was handed the ultimate salvation: environmentalism. Now the experts will regulate your life not in the name of the proletariat or Fabian socialism but -- even better -- in the name of Earth itself.

        Environmentalists are Gaia's priests, instructing us in her proper service and casting out those who refuse to genuflect. (See Newsweek above.) And having proclaimed the ultimate commandment -- carbon chastity -- they are preparing the supporting canonical legislation that will tell you how much you can travel, what kind of light you will read by, and at what temperature you may set your bedroom thermostat.

        (Yikes!) Only Monday, a British parliamentary committee proposed that every citizen be required to carry a carbon card that must be presented, under penalty of law, when buying gasoline, taking an airplane or using electricity. The card contains your yearly carbon ration to be drawn down with every purchase, every trip, every swipe.

        There's no greater social power than the power to ration. And, other than rationing food, there is no greater instrument of social control than rationing energy, the currency of just about everything one does and uses in an advanced society.

        So what does the global warming agnostic propose as an alternative? First, more research -- untainted and reliable -- to determine (a) whether the carbon footprint of man is or is not lost among the massive natural forces (from sunspot activity to ocean currents) that affect climate, and (b) if the human effect is indeed significant, whether the planetary climate system has the homeostatic mechanisms (like the feedback loops in the human body, for example) with which to compensate.

        Second, reduce our carbon footprint in the interim by doing the doable, rather than the economically ruinous and socially destructive. The most obvious step is a major move to nuclear power, which to the atmosphere is the cleanest of the clean.

        But your would-be masters have foreseen this contingency. The Church of the Environment promulgates secondary dogmas as well. One of these is a strict nuclear taboo.

        Rather convenient, is it not? Take this major coal-substituting fix off the table, and we will be rationing all the more. Guess who does the rationing.
'Unburnable carbon' perspective (3/13)
        Headline:  "Proven Fossil Fuel Reserves Contain 5x the Carbon We Can Burn Before Destroying Our Climate". I heard this quoted by economist Jeremy Grantham to Charlie Rose on TV.

Summary of the 'unburnable carbon' argument

      ** "If we're going to keep temperature rise below 2°C (a figure it increasingly appears is still too high to avoid some serious climate impacts, but it is internationally agreed to), then we have about 565 gigatons more CO2 we can send into the atmosphere over the next four decades or so. Then consider: The amount of carbon contained in the proven coal, oil and gas reserves of national oil companies and private corporations is about five times higher than this, 2,795 gigatons.
        Yes, this coal and gas and oil is still technically in the soil. But it's already economically above ground – it's figured into share prices, companies are borrowing money against it, nations are basing their budgets on the presumed returns from their patrimony. It explains why the big fossil-fuel companies have fought so hard to prevent the regulation of carbon dioxide – those reserves are their primary asset, the holding that gives their companies their value. (It is) calculated that at today's market value, those 2,795 gigatons of carbon emissions are worth about $27 trillion. Which is to say, if you paid attention to the scientists and kept 80 percent of it underground, you'd be writing off $20 trillion in assets!"
        "Putting a price on carbon would reduce the profitability of the fossil-fuel industry. After all, the answer to the question "How high should the price of carbon be?" is "High enough to keep those carbon reserves that would take us past two degrees safely in the ground." The higher the price on carbon, the more of those reserves would be worthless. This tells you how unlikely this is to come about, unless as one source says a hurricane puts all of Manhattan underwater, but didn't part of lower Manhattan already to under water in 2012 and no one paid much attention."
        I spend several hours trying to track down the x5 numbers to confirm them, and while I get numbers in the ballpark, it looks to me like a lot of the numbers thrown around are squishy. It is especially difficult to figure total proven reserves, since states often keep this secret. Also it is tricky to figure how much of exotic sources of oil and gas, like from shale, should be included.

Framing the debate
        Nevertheless the 'unburnable carbon' picture is an effective, simple way to frame the CO2 debate:

        1) How much CO2 must be emitted into the atmosphere by man to reach a (consensus) upper limit of temperature rise? How much of this CO2 budget has already be used, and how much remains for the future?

        The baseline temperature rise threshold (from pre-industrial times) is generally given as a 2C rise corresponding (roughly) to a doubling of the 278 ppm pre-industrial levels of CO2 to a 550 ppm. But this target was set in 1996 and current thinking is 3/4ths of this rise (or 1.5C) is more like it. (Hansen based on studies of the last ice age cycle wants CO2 levels reduced from current 395 ppm to 350 ppm.)
        The current CO2 level is 395 ppm, which is a 117 ppm rise from pre-industrial levels, and it has caused about 0.8C (surface) warming. Hence to limit the additional temperature rise to 1.2C (for a 2C threshold) means the budget for allowable future CO2 emissions is 150% of what already has been emitted. (Note this assumes that the fraction of CO2 emitted that ends up in sinks remains constant, currently estimated by one source as 45% remains in the atmosphere and 55% is quickly absorbed by the ocean and soils.)

        Total man made emissions to date since 1751 is 356 Gton of CARBON (current annual emissions at 8.2 billion metric tons of carbon) says Oak Ridge National Lab. If this has produced a 0.8C rise, then by simple scaling the future emission budget is 150% or 534 Gton of carbon or 1,950 Gton of CO2.  But Carbon Tracker (investment report) going out only the next 40 years and using a 20% risk of 2C comes up with the substantially lower figure of 565 Gton of CO2. (Factor of 3.5 here between sources, which smells like it could be related to the confusion of some sources being in CO2 and some in carbon, since the molecular weight ratio of CO2/C = (12 +32)/12 = 3.66)

        2) Compare future budget CO2 emissions to the potential CO2 emissions of proven reserves (still in the ground)
        Carbon Tracker using published reserves of the 100 leading coal companies and 100 leading oil companies comes up with a potential CO2 emissions just from these sources of 745 Gton of CO2, then waving their arms, for example, these numbers probably don't include Saudia Arabia whose reserves are not published, comes up with a potential CO2 emission from all sources of coal, oil and gas proven reserves x3.75 larger or 2,795 gigatons.
        The Carbon Tracker numbers of 2,795 Gtons of potential CO2 vs maximum allowable 565 Gton of course makes for good headlines, because the potential emissions are FIVE times higher than what amount needed to cook the planet.

Another perspective
       A couple of weeks after I see Jeremy Grantham on Charlie Rose this same argument shows up in Sullivan's blog.

        -- "Eduardo Porter (on NYT blog) calculates that keeping global warming below the 2°C limit recommended by most experts ”probably requires that a good share of the world’s fossil fuel remains untapped". Fatih Birol, chief economist of the International Energy Agency, told me the atmosphere could absorb at most another one trillion tons of CO2. It got almost 32 billion tons in 2011 alone, 3.2 percent more than the year before.  Even if emissions were to remain at the same level as last year — a highly unlikely prospect given the rapid growth of energy consumption in countries like China — the global economy, in about 30 years, would have to stop relying on fossil fuels entirely."

        "Most of the carbon in the ground is in the form of coal. But the world’s known reserves of oil and gas contain about one trillion tons of CO2. Applying Mr. Birol’s limit would require Saudi Arabia, Gazprom and Exxon to leave some of their reserves in the ground. They are unlikely to take kindly to this."

        Note, there appears to be a factor of 2 flaw in the annual CO2 number above: CO2 sink is ignored. The curve below shows the Dept of Energy give the annual CO2 emissions as 32 Gtons, but only about half of the emitted CO2 is held by the atmosphere for any appreciable time, the other half is quickly absorbed by oceans and soil.
        Temp threshold:                                                      2C rise (above pre-industrial baseline) (same)
        Additional CO2 atmosphere can absorb:                ('at most') 1 trillion ton vs 565 gigatons (odds of 20%, Carbon Tracker)
        Reserves:                                                                1 trillion tons (oil and gas ) vs 745 Gton (top 100 oil, gas and coal companies)
        Source                                                                    International Energy Agency vs Carbon Tracker

Kicker --- a new carbon source
        Minutes after I finished writing above I find an article in today's NYT that Japan has been drilling into offshore methane hydrate reservoirs and has made a breakthrough producing a gas flare from 'flammable ice'. Here's the kicker: "Experts estimate that the carbon found in gas hydrates worldwide totals at least twice the amount of carbon in all of the earth’s other fossil fuels" Whoops, how to leave next generations with a really scewed up planet.

        Identity: 1 billion tons of carbon = 1 gigaton of carbon = 3.66 billion tons of CO2 [from ratio of (16 + 16 + 12)/12]
        393 ppm (by volume) is fraction of atmosphere that is CO2 with increase of 1.7 ppm/year
        preindustrial baseline CO2 level is 278 ppm