Brown clouds boost global warming - Aerosols over Asia incriminated in Himalayan glacial melting.

news@nature.com ^ | 1 August 2007 | Daniel Cressey

[neverdem]

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Published online: 1 August 2007; | doi:10.1038/news070730-6

Brown clouds boost global warming

Aerosols over Asia incriminated in Himalayan glacial melting.

Daniel Cressey

Clouds of pollution sit over southern Asia for half the year.NASA/GODDARD SPACE FLIGHT CENTER/J. SCHMALTZ

Tiny particles of pollution may be causing as much warming as greenhouse gases over southern Asia. The clouds of aerosol particles are contributing to the potentially devastating melting of Himalayan glaciers, say researchers.

Using data from unmanned aircraft flying through 'brown clouds' of aerosol pollution over the Indian Ocean, US researchers found the zone of the atmosphere containing the clouds is warming by 0.25 ºC, compared with 0.10 ºC per decade at ground level.

The Himalayas and the clouds occupy the same zone of the atmosphere, so the extra warming could be accelerating glacial retreat.

"This is a big topic of conversation over there [in India]. Much of the water supply of north and central India is from major rivers fed by glaciers in the Himalayas," says study author David Winker of the NASA Langley Research Center in Virginia.

Temperatures rising

On a global scale, clouds of aerosols from biomass burning and fossil fuel consumption cool the atmosphere by reflecting sunlight back into space. But the particles also absorb solar radiation, and it has been suspected they could warm certain levels of the atmosphere.

"It is becoming more obvious that the role of aerosols is not as simple as we once thought," says Piers Forster, an Earth scientist at the University of Leeds, UK. "They don't just provide cooling, they're actually giving far more complicated and regional changes."

Direct measurements of the effects of aerosols are difficult, and satellite measurements have been available for only five years. To investigate the question, in March 2006 Winker and his colleagues flew 18 unmanned aircraft missions from the small island of Hanimaadhoo in the Maldives. They report their results in Nature¹.

Three aircraft flew over the Indian Ocean simultaneously at between 0.5 and 3 kilometres above sea level. In the second half of the month — when there was heavy pollution arriving from southern Asia — the heating rate of this band of the atmosphere more than doubled.

Occurring annually, Asian brown clouds can cover parts of southern Asia, as well as the Arabian Sea and the Bay of Bengal, from November to April².

Melting ice

Using simulations of atmospheric heating from 1950 to the present, the team determined that brown clouds plus greenhouse gases contributed 0.15 ºC to the warming trend of 0.25 ºC per decade in this part of the atmosphere.

"The data show the brown-cloud heating is as much as 50% of the background heating of the atmosphere," says the study's leader, climatologist Veerabhadran Ramanathan of the Scripps Institution of Oceanography in San Diego, California.

The simulation results are similar to observations, he adds. "Glaciologists have shown the Himalayan region has been warming by a quarter of a degree per decade. That is almost twice the warming trend of the global warming."

"[Aerosols] are very important on the regional scale," says meteorologist Eleanor Highwood of the University of Reading. Using these aircraft to take direct measurements is a step forward, she adds: "I'd love one."

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References

1. Ramanathan, V. et al. Nature 448, 575-578 (2007). | Article |
2. Ramanathan, V. et al. Curr. Sci. 83, 947-955 (2002).

[neverdem]

Ping

[MistrX]

Who is making these new brown clouds?
Who is making these clouds so brown?
Who is making these new brown clouds?
Better go ask a philostopher.

[ari-freedom]

people.
but...not the people the enviros want to blame

[knarf]

bull farts

[beethovenfan]

Al Gore’s pontifications from his ass.

[knarf]

No ... that would be bullshit farts

[sourcery]

Basic References:

• Hostages to a hoax
• Water Experts Find Earth’s Warming, Rainfall Linked to Sun
• Milankovitch Cycles and Glaciation
• The Myth of Dangerous Human-Caused Climate Change (PDF)
• Up against the warming zealots
• When Physics Trumps Hysteria in Global Warming
• Environmental Effects of Increased Atmospheric Carbon Dioxide
• Global Warming: Forecasts by Scientists versus Scientific Forecasts
• Geophysical, archeological and historical evidence support a solar-output model for climate change (PDF)
• Gamma rays and climate (PDF)
• Temperature vs. Cosmic Ray Flux
• Linkages between solar activity, climate predictability and water resource development (PDF)
• Proof on Ice: Southern Greenland Was Once Green; Earth Warmer
• Global Warming and Nature's Thermostat
• The Past and Future of Climate (PDF)
• The Great Global Warming Swindle
• IceCap

Lawrence Solomon's "The Deniers" (a series of articles on the view of scientists who have been labelled "Global Warming Deniers"):

• Science, not politics
• Statistics needed
• The original denier: into the cold
• End the chill
• They call this a consensus?
• The limits of predictability
• Unsettled science
• Models trump measurements
• The ice-core man
• The hurricane expert who stood up to UN junk science
• Polar scientists on thin ice
• The sun moves climate change
• Bright sun, warm Earth. Coincidence?
• Look to Mars for the truth on global warming
• Read the sunspots
• Forget warming - beware the new ice age
• Little Ice Age is still with us
• Fighting climate 'fluff'

Other References:

• Alarmist global warming claims melt under scientific scrutiny
• The Global Warming Myth
• Global Warming: A Chilling Perspective
• Father of Climatology Throws Up at the Thought of Al Gore's 'An Inconvenient Truth'
• IPCC Scientists Challenge Al Gore’s View of Global Warming Consensus
• Swedish Scientist Accuses UN's IPCC of Falsifying Data and Destroying Evidence
• CO2 Science
• Global Warming and Climate Forcing by Recent Albedo Changes on Mars
• Climate Momentum Shifting: Prominent Scientists Reverse Belief in Man-made Global Warming - Now Skeptics
• The Real 'Inconvenient Truth'
• New findings indicate today's greenhouse gas levels not unusual
• Climate Change: Incorrect information on pre-industrial CO2
• Global Warming as a Religion
• I Was On the Global Warming Gravy Train (By David Evans)
• Global Warming: it's not caused by greenhouse gases says academic
• Still Waiting for Greenhouse
• GREENIE WATCH
• Why Global Warming Would be Good for You
• Global Warming Primer (PDF)
• Global Warming: An Official Pseudoscience
• Sun's Output Increasing in Possible Trend Fueling Global Warming
• Fiddler On The Roof
• Debating Global Warming
• Climate Resistance

[AngelesCrestHighway]

AlGores inconvenient Brown Clouds...

[MPJackal]

I was listening to Fox’s coverage of the bridge collapse, when they had Greta Wilson (I think that is her name) who made the comment that is has been unusually hot in MN this summer and maybe that caused it. So Fox has the scoop “Global warming causes I-35 collapse”. Fair and balanced reporting at its finest.

[AlexW]

“unusually hot in MN this summer “

Is that even true?
Yesterday, I heard reports that weather in most of the US had been unusually cool this summer.

[rahbert]

Only TX has been cooler than normal. Southern ID was in the 112s(F) a month ago.

[traviskicks]

I thought the himmmylaian (sp) glaciers were growing.

[qam1]

When the earth was cooling between 1945-1976 they claimed it was because sulfate aerosols were masking global warming. Now they are saying that these very same aerosols are now heating the earth.

Whatever fits I guess

[noblejones]

<<
I was listening to Fox’s coverage of the bridge collapse, when they had Greta Wilson (I think that is her name) who made the comment that is has been unusually hot in MN this summer and maybe that caused it.
>>

Man, that’s Nancy Grace - Cameron Diaz - Elton John class of stupid. Way to go, Greta. You are now officially amongst the dumbest people on earth.

[chessplayer]

Does this mean the planet is doomed even sooner than the libs have been saying??? Brown clouds over Asia. Gotta be Bush`s fault.

[MPJackal]

“Is that even true?”

I have no idea. She was on the phone for the interview/report since she is from there. She said something about it being in the 90’s and she doesn’t know if that help cause the collapse, but....