Thursday, July 30, 2009

As predicted (Update below)

Eli has always been pretty good at figuring out where the fruitcake will be deposited, so a couple of weeks ago when he pointed to an editorial by Rudy Baum in C&E News (the American Chemical Society house organ)

The science of anthropogenic climate change is becoming increasingly well established. The scientific consensus on the reality of climate change has become increasingly difficult to challenge, despite the efforts of diehard climate-change deniers (for brevity’s sake, CCDs).
We were fully confident that
Rudy Baum, editor in chief of C&E News (ACS's membership magazine) had a stemwinder of an editorial in the June 22 issue which will, without a doubt, encounter much snorting in the near future to be featured in Rabett Run.
UPDATE: Thanks to Big City, we have Baum's reply to Joe the Chemist reads in part

ACS, in fact, has an official position on climate change, which is easy to find under the "Policy" section of The position statement opens with the following: "Careful and comprehensive scientific assessments have clearly demonstrated that the Earth's climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles (IPCC, 2007). There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change."

I am also struck by the contempt of many of the letter writers for the thousands of scientists who work for government agencies such as EPA, NASA, NOAA, and DOE. Their harshest vitriol is aimed at the UN's Intergovernmental Panel on Climate Change (IPCC). Many of the letters dismiss out of hand any report from IPCC or any U.S. government agency that supports the idea of human-induced global warming, calling such reports irredeemably "politicized." I am startled that they so blithely impugn the integrity of so many of their colleagues.

Baum also includes an interchange with a mysterious interlocutor, later shown to be one Steven J. Welcenbach. First we had Joe the Plumber, later shown to be Samuel Joseph Wurzelbacher who was no plumber, now we got Joe the Chemist, who has a BA and runs some sort of disposal company. Joe's Emails are right out of denialdepot
And sure enough, the harumphing(c) has begun with a whole bunch of letters, but if you actually read them, over half support Baum.

The criticisms ranges from simple, I don't know therefore everyone don't know (a
How many readers of C&EN even know why carbon dioxide is the "culprit"? How many kilocalories of infrared energy can a ton of carbon dioxide absorb? What is the amount of carbon dioxide absorbed in fresh or salt water, and how is that equilibrium impacted by temperature or other environmental factors? What are some of the other variables that can cause an increase or decrease in temperature?

To the evergreen OISM petition
Man-made global warming is a theory that is supported by a "consensus" of investigators in the field of studying the relationship of carbon dioxide in the atmosphere and its effect on Earth's global temperature. Consensus is not proof, and a petition has been signed by more than 30,000 persons with scientific academic degrees (9,000 of them having Ph.D.s) who are skeptical of global warming caused by carbon dioxide emissions.
and of course

Your editorial in the June 22 issue of C&EN was a disgrace. It was filled with misinformation, half-truths, and ad hominem attacks on those who dare disagree with you. Shameful!

Are you planning to write an editorial about the Environmental Protection Agency's recent suppression of a global warming report that goes against the gospel according to NASA Goddard Institute for Space Studies Director James Hansen? Or do you only editorialize on matters in keeping with your biased views on global warming?

It's actually quite staid (that's what editors are for silly with a balancing amount of support for Baum
The more people try to trivialize global warming, the more we and our descendants will suffer the results, some of which have already been quantified (for example, glacier melting and polar ice disappearing). Weather disruptions and shore erosion, for example, will begin to occur. The people who deny global warming are in the same class as those who rejected the negative effects of DDT, those who denied the negative effects of CFCs on the atmosphere, and so on.


Your comments about the climate-change deniers are right on target. In fact, your closing paragraph, "Sow doubt; make up statistics," etc., was one of the best summaries I've seen of the deceitful practices that the deniers are allowed to get away with.

We humans seem to learn from experience, and thus our modern systems of justice are not well geared for dealing effectively with climate-change deniers. This is a shame, because every month's delay in taking meaningful action likely will lead to more climate-related death and destruction in the future. There should be a law.

Including this from Eric Heller

I understand that letters published in C&EN do not necessarily reflect your views. I also appreciate the benefits of publishing a diversity of opinion. However, I am sure you exercise editorial discretion in choosing which letters are to be published and that you would not want to appear to be giving credibility to unscientific thinking and irresponsible conclusions.

But that is exactly what you did when you published the letter on global warming by Albert Z. Conner (C&EN, April 20, page 6). A quick Internet search reveals statements by Conner in a letter to the editor of a Delaware newspaper, complaining about higher taxes on cigarettes: The government "continue[s] to promulgate the outright lie of the dangers of secondhand smoke and the fictitious statistic that 400,000 people die each year in the U.S. from smoking." To deny the link between smoking and lung cancer and other diseases in this day and age and in face of all the evidence is absolutely inexcusable and irresponsible.

Believing that global warming is not at least partially caused by humans and believing that cigarette smoke does not cause cancer are becoming roughly equivalent in credibility. I doubt that C&EN would want to publish, in 2009, a letter that claimed that cigarette smoke does not cause cancer.

It would make the publication look frivolous and irresponsible, even if the editors disagreed with the writer's conclusions. But in 2009, denying the connection between carbon dioxide and global warming is just as frivolous and irresponsible, indeed even more so, because of the consequences of ignoring the problem.

This indeed is an excellent example of RTFR. Look at our friends over at denial central and you would think that the entire ACS membership is screaming for Baum's head. Send the guy a letter of support.

Chemical & Engineering News Letters To The EditorOur e-mail address is fax number is (202) 872-8727.

Or you can send your letter to:

C&EN Editor-in-Chief
1155--16th St., N.W.
Washington, DC 20036

Letters should generally be 400 words or fewer and should include the writer's full name, address, and home telephone; letters may be edited for purposes of clarity and space.

Tuesday, July 28, 2009


Eli has been mining Gerhard Krimms contribution to arXiv and has come up with yet another Krammi. We had a recent discussion of the surface temperature of the moon here at Rabett Run,

The Moon is a good example to contrast with the Earth. It rotates much more slowly, and therefore has a temperature distribution that approaches what is used by Gerlich and Tscheuschner to derive their "Tphys". Each point on the Moon's surface is tolerably close to radiative balance with the solar input at that point.

The Moon has an albedo of about 0.12. It therefore absorbs more of the incoming solar energy than Earth. Using the solar constant of 1369 W/m2, the absorbed radiation for the surface facing the Sun is about 1205 W/m2. Hence Teff for the Moon is (1205/4/σ)0.25 = 270K, or -3C. This is the temperature that would radiate back the solar energy, if evenly distributed over the moon. But directly facing the Sun, the temperature will be more like (1205/σ)0.25 = 382K, or 109 C. Albedo is not uniform. In any particularly dark patches, the temperature could even get up to (1369/σ)^0.25 = 394K, or 121C. On the night side, however, temperatures will fall toward absolute zero. Bear in mind that as temperatures fall, so too does the rate of emission of energy. Hence it takes a long time to fall all the way to zero. Say rather that temperatures should fall far enough for the emission of energy to be small.

Now consider data on the Moon from

Average day temperature is 107 C. Maximum day temperature is 123 C. These are close to theoretical expectation, to within a couple of percent.

The mean night temperature is -153C. This about 120K, and radiates a bit less than 12 W/m2. That's less than 1/100 of the solar constant, so the temperature has indeed fallen close to zero, using radiated energy as the basis for comparison.

There's no average temperature given, but the mid point of mean day and mean night temperatures is in the ballpark. This is -23C. And, just as should be expected, it is somewhere between Tphys (-120C) and Teff (-3C). But it is closer to Teff, because it is the cool side of the moon that is most different, in absolute temperature, from the unphysical extreme that is the basis of Gerlich and Tscheuschner's Tphys

On Earth, fortunately, we have an atmosphere that has to be heated from the surface. By basic thermodynamics, the Earth's average surface temperature is therefore substantially warmer than our airless moon. where surface radiation escapes directly to space.
but Gerhard shows a contradictory example

Figure 5: Moon's disk temperature at 2.77cm wavelength versus moon phase angle φ during two complete cycles from twice new moon via full moon to new moon again (adopted from Monstein.)
with a comment below of
Our Moon nearly satisfies the requirement of a planet without an atmosphere. It is well known that the Moon has no uniform temperature. There is not only a variation of the temperature from the lunar day to the lunar night, but also from the Moon equator to its poles.

Using Eqs. (1.4) would provide T 270 K e ≈ when the albedo, 0.12 M α = , and the emissivity, 1 M ε = (black body), are considered. However, as illustrated in Figure 5, the mean disk temperature of the Moon observed at 2.77cm wavelength by Monstein (2001) is much lower than this equilibrium temperature
There is nothing necessarily wrong with the Krammigraph (Eli has not checked, but it compares reasonably to similar ones that he has seen. What's up? Work out your answer and send it with to box tops (we are not particular about the boxes) to Rabett Run Krimmi Kontest @ yahno.con. Extra prizes for those who figure out how to send the boxtops.

ANSWER: Look carefully at the wavelength that the brightness temperature was measured at little bunnies. Hmm, 2.77 cm. That's pretty long wave. It turns out that long wavelength radiation (and 2.77 cm is pretty long wave compared to IR even which is micrometers) penetrates through about 4 to 8 times the wavelength. Thus if you use 2.77 cm, what you are measuring is the temperature of the moon 10 - 20 cm below the surface and that is a lot cooler and has a lot less variation with the diurnal cycle. What about if we measured at the surface. Well Apollo 15 left a temperature measuring instrument and this is what it found

Fig. 2. Lunar surface temperature time series from the landing site of the Apollo 15 mission. The series are part of the historical data archive PSPG-00093 of the US National Space Science Data Center. The color-coding of the temperature series used in this diagram is also used in Figs. 3 and 4.
The answer is that the Krammi did not show surface temperature, but below surface temperature.

Sunday, July 26, 2009


Eli has been asked to respond to recent posturing by various Indian officials and non-officials about their government climate change policy.

AS THE visiting US Secretary of State Hillary Clinton listened, Environment and Forests Minister Jairam Ramesh on Sunday made an apparent gesture of his anger over the ‘pressure’ exerted by the rich nations at the recent Major Economies Forum in Italy to force India into agreeing to a 2 degree C cap — one that has received much flak back here and also led to speculations over a difference of opinion between the foreign and environment ministries over the contentious issue of climate change. It means despite being one of the countries with the lowest per capita emissions, India would still need to work towards emission reductions to ensure the global temperatures do not increase beyond 2 degrees above 1990 levels even though the developed countries, the biggest emitters, have refused to agree to 40 per cent reductions by 2020, to match the cuts.

“Even with 8-9 per cent GDP growth every year for the next decade or two, our per capita emissions will be well below that of developed country averages. There is simply no case for the pressure that we, who have among the lowest emissions per capita, face to actually reduce emissions. As if this pressure was not enough, we also face the threat of carbon tariffs on our exports to countries such as yours,” Ramesh said in an obvious reference to Clinton while making his opening remarks at the ITC Green Building event at Gurgaon.
Eli had previously dealt with the per capita emissions argument but in a recent lecture at Bunny State, he pointed out some home truths:

To our Indian friends it is my sad duty to point out that among the great civilizations India will be hit first and hardest by climate change, if not within my lifetime which grows short, certainly within the next three decades. As the IPCC WPII group pointed out
Himalayan glaciers cover about three million hectares or 17% of the mountain area as compared to 2.2% in the Swiss Alps. They form the largest body of ice outside the polar caps and are the source of water for the innumerable rivers that flow across the Indo-Gangetic plains. Himalayan glacial snowfields store about 12,000 km3 of freshwater. About 15,000 Himalayan glaciers form a unique reservoir which supports perennial rivers such as the Indus, Ganga and Brahmaputra which, in turn, are the lifeline of millions of people in South Asian countries (Pakistan, Nepal, Bhutan, India and Bangladesh). The Gangetic basin alone is home to 500 million people, about 10% of the total human population in the region.

Glaciers in the Himalaya are receding faster than in any other part of the world (see Table 10.9) and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate. Its total area will likely shrink from the present 500,000 to 100,000 km2 by the year 2035 (WWF, 2005). The receding and thinning of Himalayan glaciers can be attributed primarily to the global warming due to increase in anthropogenic emission of greenhouse gases. The relatively high population density near these glaciers and consequent deforestation and land-use changes have also adversely affected these glaciers. The 30.2 km long Gangotri glacier has been receding alarmingly in recent years (Figure 10.6). Between 1842 and 1935, the glacier was receding at an average of 7.3 m every year; the average rate of recession between 1985 and 2001 is about 23 m per year (Hasnain, 2002). The current trends of glacial melts suggest that the Ganga, Indus, Brahmaputra and other rivers that criss-cross the northern Indian plain could likely become seasonal rivers in the near future as a consequence of climate change and could likely affect the economies in the region.
When that happens, not only will Indians beyond counting suffer, starve and die in disasters worse than the worst famines of the past centuries, but the basis of their religion, beliefs and civilization will become a seasonal chimera. Food and water sent as aid from the outside will at best sustain a small remnant. Can the Indian government survive such a disaster? Likely not. Nor will Indian society be able to withstand. It will wither and die on the sere ground of the Ganga valley and those who temporized today will be cursed forever.

India has three choices. It can do nothing to meet the threat, concentrating on business as usual and increasing emissions. It can posture about energy equity as a negotiating position, ensuring that not enough will be done as the inevitable half a loaf results in most of the disaster, or it can lead by example. India, in short, by searching out ways to decrease forcings, not only of CO2, but of black carbon, and of land use changes can, by demonstrating a great heart and leading by example in the spirit of Ghandi, can bring others along.

Already we see many in the developing world who would do nothing because China and India will not do everything. If India leads, can China not follow, and if India and China lead, the world must and will change.

India is between a very hard rock and a harder hard place. It cannot do nothing. It must do a lot

Let us now reason together about what actions India must take to continue developing and avoid calamity in twenty years. There are some obvious things that can be done. Solar and wind power, for example are well suited to a country where there is no existing electrical distribution network to huge numbers of villages where many live. Improved cooking stoves coupled with digestion of animal wastes currently used for cooking to yield cleaner burning fuel and fertilizers are places where research can make an almost immediate contribution. But we must take care not to rob the livelihoods of those who currently gather and supply the fuel nor neglect the value of improving the health of those who use the fuel. India has recognized the importance of land use changes in holding back global warming, and here too, the developed world can and must help. This will not be simple, but it is necessary.

Monday, July 20, 2009

On possibility and necessity

Eli has come to understand that both frequentist (Tamino) and Bayesian (James Annan) statistical descriptions have serious problems when applied to climate from scientific and policy standpoints. The mixture of the two is quadratically difficult as anybunny entangled in discussions of future changes can tell. Local responses to global trends which are worse.

There is, however, another way of looking at things, loosely described as Possibility Theory. Possibility Theory grew from studies of fuzzy sets and is useful for analyzing situations where knowlege is incomplete and was first described by Lofti Zadeh. Wikipedia, of course, has a description.

Rather than assigning a distribution of probabilities, Possibility Theory differentiates between the possibility and the necessity of an outcome. Some are beginning to use possibility theory to describe climate related issues, for example stream flow, climate scenarios. Also take a look here

Saturday, July 11, 2009

A gift for William Connolley and John Mashey

Ada, Countess of Lovelace discovers the difference engine
Via Brad de Long. In between saving the world, Eli thinks of his friends. Follow this link for more

Thursday, July 09, 2009

Eli Rabett's Simple Plan to Save the World (Part II)

About a year and a half ago, Eli provided a simple plan to save the world, something that appears to be of interest to your average Nobel Prize winner.

Nations wishing to make major progress on decreasing greenhouse gas emissions should introduce emission taxes on all products. These taxes should be levied on imports as well as domestic goods at the point of sale, and should displace other taxes, such as VAT, sales taxes, and payroll (e.g. social security, health care) in such a way that tax revenues are constant, and distributed equitably.
Recently, it has come to Eli's attention that the developing countries, specifically India, and to an extent China, are behaving badly, something that the denial-o-sphere is celebrating, if not directly, quite passive-aggressively. Even there, India's POV seems to orient towards the audience, much of this is pre-negotiation tactics. There are two principle threads to the argument, the first being that the US and the rest of the developed world own the problem. According to the principal Indian negotiator, Shyam Sara
We see no link between what the United States, as the world's largest emitter of greenhouse gases, does and India assuming legal commitments for emission reductions. The volume of US emissions today constitutes over 20 percent of the global total and 20 tons annually per person. Despite our much larger population, India produces only 4 percent of those emissions -- 1.1 tons per person. Therefore, while we would welcome a positive and forthcoming attitude on the part of a new administration to significantly reduce US emissions -- as President-elect Obama has promised -- this has no bearing on India. It will not lead India to accept rules that go beyond the current UN climate treaty, which does not stipulate legally binding reductions for developing nations.
Eli's simple plan bypasses this. While India and China may reject emissions added levies, there is not much they could do about it in their export lead economies. The second being that everyone owns a per capita emissions cap
Even though there is no legal obligation on India in this respect, the Prime Minister of India made a commitment that India's per capita emissions will at no time exceed the average of the per capita emissions of developed, industrialized countries. We have thus accepted a limit on our emissions and at the same time provided an incentive to our partners in developed countries to be more ambitious.

To wave a red flag, per capita arguments need to confront population growth. Claiming a larger emissions cap on the basis of increasing population should not exactly win any more points than similar persiflage. It is instructive to look at population growth. Europe and Japan (not shown) have essentially flat population since the 1970s, the US population has grown, but a large part of that is immigration. India, well, Eli is a compassionate, fast breeding mammal but still. OTOH, the Rabett recognizes denial when it is on display thus
Eli Rabett's Simple Plan to Save the World (Part II):
India and China and many other developing countries should reduce their emissions of black carbon by 90% or more in the next decade. This will not only significantly reduce warming of the climate, it will make a major contribution to the health of their people. Simple and economical methods of doing this are available.
Anyone doubting the dimension of the problem should read James Fallows reports from Beijing (he recently left) in the Atlantic

More on the Emissions Added Levy (Blogger is behaving badly, but the full text is still in the Google cache)
These should be introduced as an Emissions Added Levy (avoiding the bad jokes). EAL would be imposed on sale for emissions added in the preceding step and inherent to the consumption of the product, as would be the case for heating oil and gasoline. Manufacturers would pay the EAL on electricity they bought, and incorporate this and the levy on emissions they created into the price of the product they sell.
Imports from countries that do not have an EAL would have the full EAL imposed at the time of import. The base rate would be generic EALs based on worst previous practices in the countries that do have EALs, which would be reduced on presenting proof that the actual emissions were lower.
Saving the world is hard work, Eli needs a beer. Comments

Tuesday, July 07, 2009

The best of the worst

UPDATE: A new classic, commented on everywhere

McLean, J. D., C. R. de Freitas, and R. M. Carter (2009), Influence of the Southern Oscillation on tropospheric temperature, J. Geophys. Res., 114, D14104, doi:10.1029/2008JD011637.

With comments at Open Mind, Real Climate, James Empty Blog, In It For the Gold, Deltoid, More Grumbine Science and just about the entire Rabett Run Blogroll. An instant classic of denial and self regard.

John Mashey asks
Maybe the Rabett has this list stuffed in his burrow:

is there a nice list somewhere of truly awful climate papers published in otherwise-plausible-looking journals? (I.e., not E&E, or JSE, or things like that.)

The main use of this is to know where peer review seems to be failing.
But friend Cohenite already delivered and Eli blogged on it. Still, there is a fair amount of E&E in there, so here are Eli's top four.

Thomas Palm adds (see comments)

5. "Thermal pollution causes global warming" Bo Nordell, Global and Planetary Change 38 (2003) 305–312.

and another under review
4. G. V. Chilingar, L. F. Khilyuk, O. G. Sorokhtin. Cooling of Atmosphere Due to CO2 Emission, Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 30(1), 1 - 9 (2008). Actually anything by this trio. Brings incoherence to new heights.

3. Christopher Essex, Ross McKitrick, Bjorne Andresen; Does a Global Temperature Exist? Journal of Non-EquilibriumThermodynamics, 32(1) 1-27.

2. Ferenc Misckolczi; Greenhouse effect in semi-transparent planetary Atmospheres. Quarterly Journal of the Hungarian Meteorological 111(1), January–March 2007, 1–40.
Cohenite's favorite and a hot contender

1. Gerhard Gerlich and Ralf Tscheushner, Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of PhysicsInternational Journal of Modern Physics B, 23(3), 275-364 (2009). Get close and feel the spittle

Comments? Additions?.

Winter at Summit Camp

The Earth Observer, a NASA newsletter on the Earth Observation Program has been running Lora Koenigs diary describing winter at Summit Camp on the top of Greenland. Definitely worth reading.

Hello! My name is Lora Koenig and I am a remote sensing glaciologist and a new hire in the Cryospheric Sciences Branch at the NASA Goddard Space Flight Center. My research uses satellites to monitor the ice sheets and I am always interested in how well measurements from space compare to those taken on the ground.

My interest in ground truth data and learning more about ice sheets has lead me to spend this winter at Summit, Greenland (Latitude 72.5 N Longitude 38.5 W). Over the course of this weekly blog I will tell you about my life and science, in the middle of the Greenland Ice Sheet, in the middle of the winter. I will start with a quick introduction and explain how I ended up in the dark on an ice sheet.

Say it ain't so Rudy

Rudy Baum, editor in chief of C&E News (ACS's membership magazine) had a stemwinder of an editorial in the June 22 issue which will, without a doubt, encounter much snorting in the near future to be featured in Rabett Run. He starts by summarizing the situation

The science of anthropogenic climate change is becoming increasingly well established. The scientific consensus on the reality of climate change has become increasingly difficult to challenge, despite the efforts of diehard climate-change deniers (for brevity’s sake, CCDs).
and then points to recent major reports which strengthen the case for human driven climate change, the US Global Change Research Program report, a joint statement from the Presidents of the G8+5 national academies on climate change
Climate change and sustainable energy supply are crucial challenges for the future of humanity. It is essential that world leaders agree on the emission reductions needed to combat negative consequences of anthropogenic climate change at the UNFCCC negotiations in Copenhagen in December 2009. At the same time, agreement is needed on actions to ensure basic energy services are available to all of the world’s people.
Baum's close nailed it
We see here the same tactics used by other purveyors of nonsense rejected by the mainstream scientific community. Creationists, for example, only want to expose students to “both sides of the debate over origins,” ignoring the fact that there is no debate over evolution. And, of course, it’s always useful to attack the “mainstream media.”

Heartland and its ally are also flogging an 800-plus-page report, “Climate Change Reconsidered,” from the Nongovernmental International Panel on Climate Change (NIPCC)—kind of an anti-IPCC, get it?—which, of course, proves conclusively that global warming probably isn’t happening; if it is happening, it’s not due to human activity; and, besides, a “warmer world will be a safer and healthier world for humans and wildlife alike.”

Sow doubt, make up statistics, call for an “open debate,” claim that you are being “silenced and ignored by the media and politicians,” claim that your opponents are just a “few bureaucrats and environmental activists,” not real scientists—those are the tactics that will be brought to bear in the coming months by the CCDs in their attempt to derail meaningful efforts to respond to global climate change.


Monday, July 06, 2009

Reality Check

Werner Aeschbach-Hertig brings interesting news about Rabett Run's friend S. Fred Singer and the Chilingar.

Comment over there

Sunday, July 05, 2009

As the world wobbles

The issue of increased damage from extreme weather driven disasters as a result of climate change is attracts the same polemic that the gallery previously observed about climate change and global warming.

  1. Starting Position: It ain't happening
  2. Fallback Position: It has noting to do with the enhanced greenhouse effect
  3. Fallfurtherback Position: There is no scientific proof, we need more research
  4. Fallmuchfurtherback Position: If the local left (relatively) party didn't insist on building on the coast or in flood planes there would not be a problem.
  5. Fallwayfurtherback Position: What have the Bangladeshi's ever done for us?
In many ways this resembles the progression we have seen throughout the history of climate change, and the answers given by the IPCC (and previous reports).
FAR: The unequivocal detection of the enhanced greenhouse effect is not likely for a decade or more.

SAR: The balance of evidence suggests a discernible human influence on global climate (considerable progress since the 1990 report in distinguishing between natural and anthropogenic influences on climate, because of: including aerosols; coupled models; pattern-based studies)

TAR: There is new and stronger evidence that most of the warming observed over the past 50 years is attributable to human activities

AR4: Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely (> 90% certainty) due to the observed increase in anthropogenic (human) greenhouse gas concentrations.
The state of the art can be found in a new paper by Schmidt, Klemper and Hoeppe that was previously commented on at Rabett Run. Particularly interesting is the correlation between sea surface temperature and tropical cyclone damage.

The bars in the figure to the right shows adjusted losses for tropical cyclones that made landfall in the US. The adjustments take account of socio-economic changes. The black line is a ten year smoothed average. The red line is the smoothed North Atlantic sea surface temperature. The good correlation of the losses with the sea surface temperature provide a cleft stick to hoist DenialCON 2 position holders on, leaving them the oxymoric position of asserting that sea surface temperature is independent of global warming. Eli is confident that they will be up to it tho.

As Chris pointed out, the conclusion brings us pretty close to having to invoke DenialCon 4.
annual adjusted losses since the beginning of the last cold phase (1971) show a positive trend, with an average annual rise of 4% that cannot be explained by socio-economic components. This increase can at least be interpreted as a climate variability impact. There is no evidence yet of any trend in tropical cyclone losses that can be attributed directly to anthropogenic climate change. But we advance the premise that if losses are affected by natural climate fluctuations, they are also likely to be affected by additional global warming due to anthropogenic climate change. This premise is supported by indications that the intensity of tropical cyclones is affected by anthropogenic climate change."
An objection to this has been raised on the basis that the trends do not extend back to the 1950s. File that one in the wishful thinking category given the physical correlation between global warming, sea surface temperature, and tropical cyclone intensity.

See Harold, not once was the name of the The Talented mentioned or even linked to.


Wednesday, July 01, 2009

Science lurches forward again

About two years ago Stan Sanders group at JPL tossed a bombshell into our understanding of stratospheric ozone depletion, with a new, and much lower measurement of the chlorine peroxide (ClOOCl) absorption cross-section. This was a bombshell because it meant that there would be a lot less free chlorine in the stratosphere available for ozone depletion. Drew Shindell blogged on it at Real Climate, there was a bit of triumphalism on the denial beat.

The basic idea is that Cl catalyzes conversion of ozone, O3 to molecular oxygen, O2

(1) Cl + O3 --> ClO + O2
(2) ClO + O3 --> Cl + 2O2

ClO can dimerize

(3) ClO + ClO --> ClOOCl

which removes it from the catalytic cycle (1) and (2), but it can also be photolyzed

(4) ClOOCl + hv --> ClO + ClO

so the rate of photolysis, which is proportional to the absorption cross-section, determines how much ClO is available for the cycle. Because O3 absorbs most of the light at shorter wavelengths than 305 nm, for all practical purposes, only the absorption cross-section of ClOOCl above ~305 nm is important.

The rub, of course, is that to measure the absorption cross-section of a molecule, the lab bunnies need to know how much of the molecule is in the light path. This is not easy. As a matter of fact it is very tough, especially for ClOOCl because you cannot prepare a pure sample, there will always be Cl2, O2, and maybe other stuff hanging around. Before Pope, Hansen, Bayes, Friedl and Sander, others had tried to figure out the amount of ClOOCl in the light path by mass balance, starting from the initial reactant concentrations and using absorption spectroscopy in various regions of the spectrum to assign concentrations of the stable species where known. Sanders group did a spectral subtraction of the know Cl2 spectrum from the observed spectrum in the UV, which they assumed was a combination of ClOOCl and Cl2 (O2 does not absorb much until 200 nm).

The Academica Sinica group (H. Y. Chen, C. Y. Lien, W. Y. Lin, Y. T. Lee and J. J. Lin) chose a different path. They created a molecular beam containing the equilibrium mixture of ClOOCl and Cl2 and used a laser to photodisocciate (shoot out) each. Because they knew the absorption coefficient of Cl2 at the laser wavelengths, they could get the ratio of the ClOOCl to Cl2 cross-sections at each wavelength. The results are shown in the figure and agree well with earlier measurements. As they point out all three methods have their difficulties. They think that Pope, et al, overcorrected for Cl2, but that really is speculation.

This is the way that science auditing works. Comments?