The Weekly Carboholic: new data reveals human-caused warming at both poles

Posted on November 6, 2008



According to a new paper published in Nature Geoscience and available online here, scientists from the UK, US, and Australia have detected anthropogenic influence on the climate of both the Arctic and Antarctica. Ana according to a Scientific American article on the paper, one of the paper’s reviewers, Andrew Monaghan of the National Center for Atmospheric Research, believes that the paper may be understating the effect of anthropogenic carbon emissions on Antarctica. Monaghan’s reason? The new paper gives equal weight to cooling in the interior of Antarctica as to heating on the periphery, while interior cooling is suspected to be a result of the CFC-caused ozone hole.

While the paper is impressive for the data it used (100 years of Arctic temperature measurements and 50 years of Antarctic measurements from all available monitoring stations), the figures illustrate just how sparse the data set really is. If you look at the image below (Figure 2, parts c and d), all the colored sections are areas where there is sufficient data to draw conclusions from, while the gray areas have insufficient data. As is obvious, there’s a lot more gray than colored sections, and so critics could fairly attack the accuracy of the paper’s conclusions based on insufficient data. However, the authors tried to immunize themselves against such criticisms by comparing the results of their simulations and results based on their limited data with previously-generated methods for infilling the missing data developed by other researchers.

Ultimately, though, if you look at the topmost image (figure 1 from the paper), you’ll notice that the black observed line tracks most closely to the red line labeled “All”. That red line is the combined output of four climate simulations that include anthropogenic effects – the blue line is the simulation output when only natural effects such as solar irradiance and volcanism are included. In other words, only by including human influences on climate could the models be made to match reality.


Methane concentrations increase globally in 2007
According to TGDaily, a new paper on atmospheric methane from several MIT researchers suggests that new data contradicts anthropogenic global warming (AGW) and that, as the TGDaily article says:

[S]ince all worldwide levels rose simultaneously throughout the same year, it is now believed this may be part of a natural cycle in mother nature – and not the direct result of man’s contributions.

Of course, that’s not at all what the MIT researchers said. It’s true, according to a New Scientists article on the same paper, that MIT researcher Matthew Rigby is quoted as saying “The worry is that we just don’t understand the methane cycle very well.” And it’s also true that Rigby and MIT professor and co-author Ronald Prinn were surprised by the simultaneous rise in both the Northern and Southern Hemispheres, since there’s no obvious sources for massive methane releases in the Southern Hemisphere like there is in Arctic methane hydrate deposits. But they have suggested an alternative hypothesis for the rapid increase in methane concentrations, a hypothesis that has precedents in the data of prior years. It’s possible that the simultaneous change in both hemispheres is related to a breakdown in the global effectiveness of a chemical reaction in the atmosphere that breaks methane down into water and carbon dioxide.

However, it’s too early to know if the increase is a short term “blip” in methane concentration (as illustrated at several points in IPCC AR4 WG1 Chapter 2, Figure 2.4b, page 142) or whether methane concentrations will continue to grow at an accelerated rate for years or longer. If it’s the former, then it’s probably not a big deal. But if it’s the latter, then that suggests either the hydroxyl/methane reaction is breaking down (a very bad thing) or that organic decay and hydrate thawing is dumping massive, and likely increasinly so, amounts of new methane into the atmosphere.


Architect of Berkeley’s new solar plan gives Grist an update
As of yesterday, the city of Berkeley, California has started their plan to reduce the price of solar panels for residential and commercial customers by converting the tens of thousands of dollars for installation into bundled city bonds that are paid off with higher property taxes. This reduces the cost of entry and makes the repayment time for the panels independent of how long the owner will be willing to stay in the home. The hope is that this program will make people far more willing to add solar to their homes and businesses and will reduce the interest rates the homeowners will have to pay below what they’d pay if they got a straight bank loan for the solar upgrade.

Grist has a guest post on this innovative solar funding program by the architect of the program, Cisco Devries.


Two useful climate disruption maps
The progressive think tank the Center for American Progress (CAP) has put out two maps that could be quite useful for people concerned about the impact of green jobs and climate disruption on their communities. The first, the Interactive Map of the Green Recovery, shows how many jobs would be created in each state that received money from a CAP/University of Massachusetts $100 billion Green Recovery program. My home state of Colorado, for example, would receive more than $400 per person under the plan, that $2 billion total would be expected to produce almost 33,000 new jobs, and reduce the unemployment rate by between 20 and 30% (ie from 6% to between 3.6 and 4.8%).

The second map (example screen shown below) shows where a variety of climate disruption-caused problems are occurring and where they’re expected to occur as climate disruption gets worse throughout this century. Not only that, the “Human Toll of Climate Change” map shows a number of existing and projected problems on a Google map for parts of the entire planet, not just the U.S., and every data point is classified and supported with scientific research. It’s very well done and should be considered a very useful reference.

Image credits:
Nature Geoscience

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