The Weekly Carboholic: as the Arctic melts

Posted on April 1, 2009

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carboholic

arcticmethane

“I was in Siberia a few weeks ago, and I am now just back in from the field in Alaska. The permafrost is melting fast all over the Arctic, lakes are forming everywhere and methane is bubbling up out of them.”

“Lakes in Siberia are five times bigger than when I measured them in 2006. It’s unprecedented. This is a global event now, and the inertia for more permafrost melt is increasing.”

This is what University of Alaska ecologist Katey Walter is quoted as saying in a New Scientist article published last week titled Arctic meltdown is a threat to humanity. The article then proceeds to go through the worst-case scenarios that could result from the widespread warming of the Arctic, specifically changes in the thermohaline global ocean current and mass methane releases from permafrost and submarine hydrates.

Simply put, mass releases of methane could, if modelers like David Lawrence of the National Center for Atmospheric Research (NCAR) are right, create heating that feeds on itself (aka “positive feedback”) – warmer Arctic temperatures releases more methane that warms the Arctic further and so on. And if the Arctic changes enough and Greenland melts enough, then the thermohaline current could slow down, resulting in widespread changes ranging from a dramatic reduction in Asian monsoons to a general cooling of Europe. While not mentioned in the New Scientist article, the Carboholic has reported on the possibility of a weaker thermohaline current making oxygen depletion much worse throughout the global ocean, essentially making almost 2/3rds of the ocean unlivable for most existing marine life and 9% of the ocean entirely unlivable for any organism that relies on oxygen.

On potential problem is that the New Scientist article claims that climate models don’t presently include the heat of microbial decomposition of permafrost or the existence of a permanently thawed layer of permafrost that gradually grows due to said decomposition. If this is true, then it could make the real future that much worse than it already is expected to be based on existing models and trends in carbon dioxide emissions, sea level rise, et al.

It certainly doesn’t help that, after a decade of stability, the concentration of methane in the atmosphere started rising again in 2007.

As bad as all that is, there was an interesting aside in the article:

Incidentally, the changing winds might also be to blame for some of the cold and snowy weather in North America and China in recent winters, Overland says. Unusual poleward flows of warm air over Siberia have displaced cold air southwards on either side.

If true, then the unusually cold winter we’ve been having is a direct result of anthropogenic global climate disruption.

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dust_lgAerosols strongly influence tropical Atlantic temperatures

Studies have found that aerosols like volcanic ash, pollution, and dust can influence climate on a regional and global scale. The most famous recent example of this is the global cooling that happened for several years after the eruption of Mount Pinatubo in 1991 as a result of the sulfur dioxide blown high into the stratosphere, but other aerosols can have more subtle effects. A new study authored by scientists out of the University of Wisconsin-Madison and NOAA/NESDIS/NCDC shows that dust from western Africa, especially the Sahara, has a significant effect on the tropical northern Atlantic ocean (paper available indirectly via this site).

The northern tropical Atlantic (NTA) ocean has warmed more than almost any other are of the global ocean, but there’s been only limited agreement as to what the cause for the significant warming has been. Study authors Amato Evan, Daniel Vimont, Andrew Heidinger, James Kossin, and Ralf Bennartz analyzed the amount of dust over the NTA and found that between 65% and 70% of the observed warming could be a result of aerosols. Specifically, lower amounts of Saharan dust led to more insolation of the NTA and thus higher sea surface temperatures. That means that, of the observed 0.7 degrees C rise in the NTA, approximately 0.5 degrees C is believed to be a direct result of lower aerosol levels in the atmosphere.

The authors analysis doesn’t include a lot of factors that go along with changes in the amount of dust in the air, such as changes in cloudiness, humidity, and some of the feedback mechanisms between the atmosphere and the surface of the NTA. For that reason, the authors will almost certainly continue their research, as well they should. But their conclusion bears consideration:

[S]tudies have estimated a reduction in Atlantic dust cover of 40-60% under a doubled carbon dioxide climate, which, based on model runs with an equivalent reduction of the mean dust forcing, could result in an additional 0.3-0.4 deg C warming of the northern tropical Atlantic.

In other words, the very region responsible for spawning nearly all Atlantic hurricanes could see the sea surface temperatures rise significantly. And that could result in significantly more intense hurricanes (as they’re powered by energy transferred from the sea surface into the atmosphere) and more precipitation for the northern coast of South America. I think it’s safe to say that more research is warranted.

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Latest EIA Annual Energy Outlook updates energy consumption estimates for 2030

Last week, the Energy Information Administration (EIA) released it’s Annual Energy Outlook 2009 (AEO2009). This report updates the official projections for how much energy will be consumed, produced, imported, and exported by the United States from the end of 2007 through 2030. The AEO2009 estimates a “reference case” that has includes the existing legislation and reasonable economic growth estimates, but also a number of alternate cases that attempt to capture the effects of higher or lower consumption, changes in legislation, migration from coal to natural gas or renewables, and so on. And this year, the new AEO has some good news as well as some bad news.

The good news about coal is that coal-fired electricity is expected to shrink as a percentage of total electricity generation, from 49% in 2007 to 47% in 2030. The bad news is that the total amount of electricity produced by coal plants is still expected to increase from 2,021 billion kilowatts (kW) to 2,415 billion kW.

Similarly, the good news about hydroelectric and “other” technologies including wind and solar is that they’re expected to increase from 374 to 758 billion kW by 2030, but the bad news is that’s only an increase from 8.9% of total electricity generation in 2007 to 14.6% in 2030, according to the EIA reference case.

More good news: sulfur dioxide, nitrogen oxide, and mercury emissions are expected to drop significantly from present levels.

More bad news: total transportation fuel consumption is expected to rise by over 16% by 2030, and per capita carbon dioxide emissions are expected to drop from 19.7 to 17.1 tons. Not much improvement there, given the need to address anthropogenic climate disruption.

And there’s some mixed news too. Shale oil is not expected to start producing before 2023 at the earliest, and the EIA didn’t even try to estimate its impacts in any of their cases. Motor gasoline is expected to cost $3.88 per gallon in 2007 dollars (significantly more than that when accounting for predicted inflation). And that’s with drilling on the outer continental shelf – remove OCS drilling and the price per gallon goes up a whopping three cents.

All that said, there’s a major caveat that has to be added to all this information – the EIA is not allowed to estimate changes in legislation that are pending in their Annual Energy Outlooks. So if carbon capitalism is implemented, that will change these estimates. As will a renewable energy standard, more stringent CAFE standards, and so on.

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Large insurers required to disclose climate risks to regulators

Last week, InsuranceNews.net reported that the National Association of Insurance Commissioners (NAIC) has started requiring large insurers to tell regulators what risks climate disruption poses to the company and how the company is responding to those risks. While this applies only to insurers with more than $500 million in premiums per year, NAIC also suggested that smaller insurance companies voluntarily reveal their risks and responses as well.

The NAIC has crafted an eight question survey that the insurers will have to answer and that will be publicly available from insurance regulators. The questions include “how an insurer is altering its risk management and catastrophe risk modeling, steps it has taken to engage and educate policymakers and policyholders as well as changes in its investment strategies due to the challenges presented by climate change.”

While a number of insurance and consumer groups supported this action, two insurance associations in the midwest opposed it. In the article, a representative of the National Association of Mutual Insurance Companies in Indianapolis argued that the regulators had no need to know or publicize an insurance company’s exposure to climate disruption-based risks. A spokesman for the other group, Property Casualty Insurers Association of America in Des Plaines, Illinois, felt that climate models were too uncertain to be able to accurately assess the the risks.

Both companies are in coal-heavy states – Indiana and Illinois.

Image credits:
Jewishjournal.com
MODIS

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