Archive for Wednesday, April 23, 2008

Arctic haze may hold clues to melting

April 23, 2008

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— Visitors to Alaska often marvel at the crisp, clear air. But the truth is, the skies above the Arctic Circle work like a giant lint trap during late winter and early spring, catching all sorts of pollutants swirling around the globe.

In recent weeks, scientists have been going up in government research planes and taking samples of the Arctic haze in hopes of solving a mystery: Are the floating particles accelerating the unprecedented warming going on in the far north?

While carbon dioxide and other greenhouse gases that trap the Earth's heat are believed to be the chief cause of global warming, scientists suspect airborne particles known as aerosols are also contributing to the Arctic meltdown.

To prove their suspicions, they are analyzing the haze, using mass spectroscopy and other technology to identify what is in it, where it came from and how it interacts with the clouds, the sunlight and the snow cover.

Their air samples have been found to contain dust from Asian deserts, salts that swell up with moisture, particles from incomplete burning of organic material from forest and cooking fires, and all manner of nasties emitted by automobile tailpipes, factory smokestacks and power plants.

Collectively, they are a United Nations of pollution. Through chemical analysis, the particles can be traced to their sources throughout Asia, Europe and North America.

"The Arctic is a melting pot for mid-latitude pollution," said Daniel Jacob, a Harvard scientist taking part in the research. "We have signatures of just about everything you can imagine flying around in the Arctic."

The research is being conducted separately by NASA, the Department of Energy and the National Oceanic Atmospheric Administration, and involves about 275 scientists and support staff and five aircraft.

The researchers are building on the work of a University of Alaska Fairbanks atmospheric scientist who arrived 35 years ago. Glenn Shaw took a light meter to Barrow, America's northernmost community, figuring he could document the clearest skies on the globe and perhaps get a mention in a scientific journal.

"I was expecting to set a record," he said, "because at the northern tip of Alaska, there's no industry, and the idea was that this must be the cleanest place, essentially, almost, on planet Earth."

He was wrong. Shaw detected a phenomenon later dubbed Arctic Haze that indicated the skies above Barrow and all the way to the North Pole collect pollutants.

"The important thing was, and is, this is aerosol material that is traveling over three or four thousand miles, which was unprecedented at the time," he said.

The focus on greenhouse gases has made it difficult to bring other possible agents of climate change into the discussion, Jacob said. But last summer's startling melt-off of Arctic sea ice has lent new urgency to the research blitz now under way.

It is well-established that soot that has fallen on snow can absorb heat from the sun and cause melting. But the researchers are also interested in what the soot does while it is still airborne.

Among other things, they want to know how the size and density of the particles alter the type and longevity of clouds, said Greg McFarquhar of the University of Illinois. Also, they want to find out whether the airborne particles reflect heat back into space or absorb it.

Comments

gr 7 years ago

"The focus on greenhouse gases has made it difficult to bring other possible agents of climate change into the discussion, Jacob said. "I thought this was an established "fact". You mean there might be other issues that keep coming up? Either way, I'm sure the wackos will find some way to blame it on humans and find some creative way of manipulating them."But last summer's startling melt-off of Arctic sea ice has lent new urgency to the research blitz now under way."Blitz. - Lowell!

just_another_bozo_on_this_bus 7 years ago

Does harderfaster have anything of substance to say, or just more ad hominem BS?

just_another_bozo_on_this_bus 7 years ago

You're right gr, there is no cause at all for any of this stuff. The billions of tons of stuff that humans release into the atmosphere in ever-increasing quantities is just irrelevant. It's just another case of "sh*t happens, but if our superstitions are practiced just right, gawd will protect us.

gr 7 years ago

bozo, I'm surprised that even though your belief system is being shattered, you aren't missing a beat but still going with it. What does pollution have to do with your imaginary CO2 beliefs?

just_another_bozo_on_this_bus 7 years ago

Are you getting dizzy with all that circular "logic," gr?

gr 7 years ago

From the link:"Disconcerting as it may be to true believers in global warming, the average temperature on Earth has remained steady or slowly declined during the past decade, despite the continued increase in the atmospheric concentration of carbon dioxide, and now the global temperature is falling precipitously.""All four agencies that track Earth's temperature (the Hadley Climate Research Unit in Britain, the NASA Goddard Institute for Space Studies in New York, the Christy group at the University of Alabama, and Remote Sensing Systems Inc in California) report that it cooled by about 0.7C in 2007. This is the fastest temperature change in the instrumental record and it puts us back where we were in 1930.""The previous time a cycle was delayed like this was in the Dalton Minimum, an especially cold period that lasted several decades from 1790.""Global warming would increase agricultural output, but global cooling will decrease it.""Millions will starve if we do nothing to prepare for it (such as planning changes in agriculture to compensate), and millions more will die from cold-related diseases.""On the other hand, it must be noted that the cooling in 2007 was even faster than in typical glacial transitions. If it continued for 20 years, the temperature would be 14C cooler in 2027."Does that help you any?(I must admit it sounds a little of the chicken-little type of news that you base your belief system on)

georgeofwesternkansas 7 years ago

If the c02 produced in Kansas stays in the air in Kansas, how did this polution get there?? Do they have coal fired plants in this part of the world??

just_another_bozo_on_this_bus 7 years ago

Nothing like an opinion piece from Fox News, trying to dredge up sunspots again, when it's pretty clear that the cause of the cooling is the transition form la nina to el nino, which has been shown to have a temporary cooling effect, unlike the "sunspot" theory.

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