A new study on the causes of Arctic warming and melting…
I wrote on this issue in the past. Now a new study suggests that…
“We will have very little leverage over climate in the next couple of decades if we’re just looking at carbon dioxide,” Shindell said. “If we want to try to stop the Arctic summer sea ice from melting completely over the next few decades, we’re much better off looking at aerosols and ozone.”
The study also implicates soot in the melting of arctic ice.
Sulfates, which come primarily from the burning of coal and oil, scatter incoming solar radiation and have a net cooling effect on climate. Over the past three decades, the United States and European countries have passed a series of laws that have reduced sulfate emissions by 50 percent. While improving air quality and aiding public health, the result has been less atmospheric cooling from sulfates.
At the same time, black carbon emissions have steadily risen, largely because of increasing emissions from Asia. Black carbon — small, soot-like particles produced by industrial processes and the combustion of diesel and biofuels — absorb incoming solar radiation and have a strong warming influence on the atmosphere…
Since decreasing amounts of sulfates and increasing amounts of black carbon both encourage warming, temperature increases can be especially rapid. The build-up of aerosols also triggers positive feedback cycles that further accelerate warming as snow and ice cover retreat.
Interesting, the melting of the arctic is one of the main arguments for anthropogenic carbon dioxide as warming agent. But Roger Pielke has been saying all along…
In terms of climate change and variability on the regional and local scale, the IPCC Reports, the CCSP Report on surface and tropospheric temperature trends, and the U.S. National Assessment have overstated the role of the radiative effect of the anthropogenic increase of CO2relative to the role of the diversity of other human climate forcings on global warming, and more generally, on climate variability and change.
