Recently in Climate Category

This week brings news of 1) a dramatic improvement in the estimates of how soil carbon content is related to atmospheric carbon concentration and 2) the exposure of some really crappy work on the rate of melting of Himalayan glaciers by the International Panel on Climate Change (IPCC).  The soil carbon work is Good Data, but Bad News if you care about the effects of high atmospheric carbon concentrations, while the Himalayan glacier story is all about terrible peer review and Bad Data (non-existent data, actually), which doesn't help anybody figure out the real story on water supplies in Asia.

First up, a paper from this week's PNAS by Breeker et al at UT Austin, "Atmospheric CO2 concentrations during ancient greenhouse climates were similar to those predicted for A.D. 2100".  Already from the title you can see where this is going.

The problem Breeker and colleagues address is the following: how do you correlate the carbon content of fossil soils with prevailing atmospheric carbon dioxide concentrations?  Well established methods exist for measuring the carbon content of compounds in fossil soil, but less certain were conditions under which chemical reactions produce those particular compounds.  It turns out that model used to infer atmospheric CO2 contained an error.  Breeker determined that the primary compound assayed when determining soil carbon content forms at much lower atmospheric CO2 concentrations than had been assumed.

Prior attempts to correlate soil carbon (and by proxy atmospheric CO2) with greenhouse periods in Earth's climate had concluded that warm periods experienced CO2 concentrations of much greater than ~1000 parts per million (ppm).  Therefore, one might conclude that only when average atmospheric CO2 spiked above this level would we be in danger of experiencing greenhouse gas warming that threatened glaciers.  The correction supplied by Breeker substantially lowers estimates of the average CO2 concentration that is correlated with continental glacial melting.  Eyeballing the main figure in the paper, it looks to me like we could be in real trouble above 450 ppm -- today we are at just shy of 390 ppm and there is no sign we will be slowing down anytime soon, particularly if India and China keep up their pace of development and emissions.

Looking forward to 2100, things get a touch squiffy because Breeker relies on an estimate of CO2 concentrations that come out of model of global economic activity.  So the title of the paper might be a tad alarmist, simply because 2100 is a long way out for any model to be taken too seriously.  But the correction of the paleodata is a big story because at minimum it reduces the uncertainty of atmospheric CO2 levels, and it appears to clarify the connection between CO2 levels and continental glaciation.  More work is needed on the later point, obviously, or this paper would have been on the cover of Science or Nature.

Now on to a serious screw-up at the IPCC.  Elisabeth Rosenthal at the NYT is reporting that "A much-publicized estimate from a United Nations panel about the rapid melting of Himalayan glaciers from climate change is coming under fire as a gross exaggeration."  Here is Andrew Revkin's take on DotEarth, and anyone interested in this story should read through his post.  The comments are worth perusing because some of the contributors actually seem to have additional useful knowledge, though, of course, nut jobs aplenty show up from both sides of the debate over climate change.

In a nutshell, the issue is that the most recent IPCC chapter on glaciers contained a conclusion, advertised as real analysis, that was in fact a speculation by one scientist promulgated through the popular press.  The authors of that section of the IPCC report may have been warned about the unsubstantiated claim.  Contradictory data and analysis seems to have been ignored.

So, to be frank, this is a giant, inexcusable fuck-up.  The IPCC is composed of so many factions and interest groups that this may be a case of simple blundering or of blatant politicization of science.  But here is the beautiful thing about science -- it is self-correcting.  It may take a while, but science always wins.  (See also my post of a couple of years ago, Dispelling a Climate Change Skeptic's "Deception".)  Every newspaper story I have seen about this particular IPCC screw-up notes that it was brought to light by...wait for it...a climate scientist.  It is an excellent public airing of dirty laundry by the community of science.  So while this episode demonstrates that the last official IPCC report on glacial melting in the Himalayas should not be used for any sort of scientific policy recommendation or economic forecast, you can bet that the next report will do a damn fine job on this topic. 

Finally, whether or not the IPCC gets its act together, there are plenty of good data out there on the state of the planet.  Eventually, Science -- with a capital S -- will get the right answer.  The same methodical process that has resulted in computers, airplanes, and non-stick fry pans will inevitably explain what is really going on with our climate.  And if you use computers, fly on airplanes, or eat scrambled eggs then you are implicitly acknowledging, whatever your political or religious persuasion, that you believe in science.  And you better, 'cause science always wins.

A fortnight ago the World Wildlife Fund released a report pushing industrial biotech as a way to increase efficiency and reduce carbon emissions.  Interesting.  Of course, industrial biotech doesn't necessarily require direct genetic modification, but the WWF must know that is an inevitable consequence of heading down this road.  More on this after I get a chance to read the report.

News today that a federal judge has rejected the approval of GM sugar beets by the USDA.  The ruling stated that the government should have done an environmental impact statement, and is similar to a ruling two years ago that led to halting the planting of GM alfalfa.  As in that case, according to the New York Times, "the plaintiffs in the [sugar beet] lawsuit said they would press to ban planting of the biotech beets, arguing that Judge White's decision effectively revoked their approval and made them illegal to grow outside of field trials."  The concern voiced by the plaintiffs, and recognized by the judge, is that pollen from the GM beets might spread transgenes that contaminate GM-free beets.

A few other tidbits from the article: sugar beets now supply about half the US sugar demand, and it seems that GM sugar beets account for about 95% of the US crop (I cannot find any data on the USDA site to support the latter claim).  A spokesman for the nation's largest sugar beet processor claims that food companies, and consumers, have completely accepted sugar from the modified beets -- as they should, because it's the same old sugar molecule. 

I got lured into spending most of my day on this because I noticed that the Sierra Club was one of the plaintiffs.  This surprised me, because the Sierra Club is less of a noisemaker on biotech crops than some of the co-plaintiffs, and usually focuses more on climate issues.  Though there is as yet no press release, digging around the Sierra Club site suggests that the organization wants all GM crops to be tested and evaluated with an impact statement before approval.  But my surprise also comes in part because the best review I can find of GM crops suggests that their growing use is coincident with a substantial reduction in soil loss, carbon emissions, energy use, water use, and overall climate impact -- precisely the sort of technological improvement you might expect the Sierra Club to support.  The reductions in environmental impact -- which range from 20% to 70%, depending on the crop -- come from "From Field to Market" (PDF) published earlier this year by the Keystone Alliance, a diverse collection of environmental groups and companies.  Recall that according to USDA data GM crops now account for about 90% of cotton, soy, and corn.  While the Keystone report does not directly attribute the reduction in climate impacts to genetic modification, a VP at Monsanto recently made the connection explicit (PDF of Kevin Eblen's slides at the 2009 International Farm Management Congress).  Here is some additional reporting/commentary.

So I find myself being pulled into exploring the cost/benefit analysis of biotech crops sooner than I had wanted.  I dealt with this issue in Biology is Technology by punting in the afterword:
 

The broader message in this book is that biological technologies are beginning to change both our economy and our interaction with nature in new ways.  The global acreage of genetically modified (GM) crops continues to grow at a very steady rate, and those crops are put to new uses in the economy every day.  One critical question I avoided in the discussion of these crops is the extent to which GM provides an advantage over unmodified plants.  With more than ten years of field and market experience with these crops in Asia and North and South America, the answer would appear to be yes.  Farmers who have the choice to plant GM crops often do so, and presumably they make that choice because it provides them a benefit.  But public debate remains highly polarized.  The Union of Concerned Scientists recently released a review of published studies of GM crop yields in which the author claimed to "debunk" the idea that genetic modification will "play a significant role in increasing food production"  The Biotechnology Industry Organization responded with a press release claiming to "debunk" the original debunking.  The debate continues.

Obviously we will all be talking about biotech crops for years to come.  I don't see how we are going to address the combination of 1) the need for more biomass for fuel and materials, 2) the mandatory increase in crop yields necessary to feed human populations, and 3) the need to reduce our climatic impacts, without deploying biotech crops at even larger scales than we have so far.  But I am also very aware that nobody, but nobody, truly understands how a GM organism will behave when released into the wild.

We do live in interesting times.

Carl Zimmer has a nice piece in Yale Enivronment360 on continued efforts to build bugs that produce fuel, "The High-Tech Search For A Cleaner Biofuel Alternative".  The article extensively quotes Steve Aldrich, President of Bio-era, on the trade-offs of using sugar cane as a source material.

Craig Venter makes an appearance arguing that the best long-term bet is to build photosynthetic bugs that use atomspheric CO2 to directly produce fuel.  Maybe.  This would require containment facilities for culturing engineered bugs, where those facilities also must capture sunlight and CO2 to feed the bugs.  The costs for this infrastructure are not insignificant, and this is exactly what is presently standing in the way of large scale algal biodiesel production.

Here is the question I keep asking in these circles: why not just grow naturally occurring algae, which can be grown at extremely high yield in a wide variety of conditions, as food for bugs hacked to eat cellulose?  If there is no algae to be had, just throw in another source of cellulose or other biomass.  There would be minimal concern over growing modified organisms that might escape into the wild.  The processing of biomass into fuel under would also be under conditions that are easier to optimize and control.

I'm not suggesting this is the only answer, but rather that it appears to balance 1) the costs of infrastructure, 2) concerns over enviromental release of genetically modified organisms, and 3) provide an efficient processing infrastructure that could use a wide variety of feedstocks.

The ongoing American Geophysical Union meeting is full of cheery news.  According to a report in the IHT, more than 2 trillion tons of landlocked ice have melted since 2003 in Greenland, Antarctica, and Alaska.  Of that, more than half occurred in Greenland, and satellite measurements confirm that the melting is accelerating.

The new results follow on James Hansen's earlier work based on data, rather than models, suggesting that both warming and sea level rise are likely happen faster than the IPCC consensus estimates (see "It's time to Invest in Water Wings"), because the IPCC models explicitly exclude the effect of ice sheet movement and landlocked ice melting.

It gets even better.  Reduced sea ice coverage is also now strongly affecting the thermal balance of the poles:

As sea ice melts, the Arctic waters absorb more heat in the summer, having lost the reflective powers of vast packs of ice. That absorbed heat is released into the air in the autumn. That has led to autumn temperatures in the last several years that are 6 degrees Fahrenheit to 10 degrees (3.5 degrees to 6 degrees) warmer than they were in the 1980s.

Warming of the land and sea are coupled: "The loss of sea ice warms the water, which warms the permafrost on nearby land in Alaska, thus producing methane," itself a potent greenhouse gas, according to Julienne Stroeve, a research scientist at the National Snow and Ice Data Center in Boulder, Colorado.  (See my previous posts: "Methane Time Bomb" and "Update".)

With respect to the anomolously high Arctic temperatures, The Independent's Steve Connor wonders "Has the Arctic melt passed the point of no return?":

The phenomenon, known as Arctic amplification, was not expected to be seen for at least another 10 or 15 years and the findings will further raise concerns that the Arctic has already passed the climatic tipping-point towards ice-free summers, beyond which it may not recover.

The coupling of land and sea warming constitute a feedback mechanism that threatens to create runaway warming and increased methane emissions, which will only make things worse.  Only more data will help resolve any remaining uncertainty.  While we gather that data, our time to fiddle is running out.