Could an L.A. Mainstay be to Blame for the Arctic's Recent Warming?
Image courtesy of NOAA
And no, as you may have already surmised, we're not talking about L.A.'s congested freeways or Hollywood — but of its longstanding smog problem. Perhaps counterintuitively, this seemingly pristine region has amassed heavy concentrations of trace gases, airborne particles and soot — courtesy of our considerable fossil fuel consumption — which scientists believe may be to blame in part for the Arctic's accelerated melting. A team of academic and government researchers will spend the next few weeks flying through this so-called "Arctic Haze" to study its impact vis-a-vis global warming — and the unprecedented rate of summertime sea ice melting.
Image courtesy of stiangd via flickr
Armed with an array of satellites, ships, ground stations and sensors, ARCPAC (Aerosol, Radiation, and Cloud Processes affecting Arctic Climate Change) scientists will attempt to gauge the roles played by airborne particles and ozone — among many other pollutants — in spurring warming in the region. Upon returning for another 3-week expedition during the summer, they hope to craft the equivalent of a "high-def movie of the atmosphere as springtime sunlight warms the region and sparks a chain of chemical reactions," lead scientist Dan Murphy, of NOAA's Earth System Research Laboratory, explained.
A related study, to be carried out later this month, will investigate the effects of similar air pollutants in the North Greenland and Barents seas; since both seas are closer to the source of air pollution — Europe — the scientists are hoping to assess the shorter term warming impact of recent emissions.
Reporting for The Christian Science Monitor, Peter Spotts notes that the first phase of the study — though only halfway completed — has already yielded some interesting insights:
Although the project is roughly halfway through its first three weeks in the field, researchers are already noting the region's role as a caldron for emissions flowing up from lower latitudes.
"We've seen European pollution, North American pollution, Russian pollution. We've seen Siberian forest-fire plumes already, in April. We've seen plumes coming all the way up from Indochina," where locals use fire to clear farmland, Dr. Jacob says. This stew is aging in the Arctic, combining to form Arctic haze.
Moreover, he says, the team has been gathering details on the haze's color, which can vary from nearly white to dark gray. The relative abundance of these different tones can play a significant role in tilting aerosols' net effect toward or away from warming.
How significant the contribution of this "Arctic Haze" to continued warming in the region remains to be seen — though the initial signs aren't promising.