Scripps Study - Complex, Alarming Results In S. Asia From Climate Warming

[hatrack]

EDIT

In a study published in the May 15 issue of the American Meteorological Society's Journal of Climate, Chul Eddy Chung and V. Ramanathan of Scripps Oceanography describe their analysis of sea-surface temperatures and a range of other data from the Indian Ocean region. In the analysis, they found that cooler-than-normal temperatures in the northern part of the ocean have weakened the natural climate circulation and monsoon conditions in the region, resulting in reduced rainfall over India and increased rainfall over the Sahel area south of the Sahara in Africa.

As the tropical Indian Ocean heats up due to greenhouse gases, the authors say, the northern Indian Ocean, which is adjacent to highly populated regions, is not warming as quickly as the rest of the ocean, resulting in increased drought conditions that could hold repercussions for more than 2 billion people in South Asia. These conditions impact a range of industries and resources, from agriculture to freshwater availability. The culprit behind the changes, the authors argue, is an ongoing and intricate clash between air pollution, greenhouse gases and naturally produced climate changes.

"It appears that the whole tropical region in this area is being pulled in different directions," said Ramanathan, director of the Center for Clouds, Chemistry and Climate at Scripps. "The observed trend of reduced sunlight reaching the Earth's surface, with compensating solar heating aloft from the pollution, also called the 'brown haze,' appears to be masking the greenhouse warming in the northern Indian Ocean, while the greenhouse warming continues unabated in the southern Indian Ocean. We are starting to see that the air pollution affects sunlight and is potentially having a major disruption of the rain patterns, with some regions getting more and some less."

In a separate but related study published in 2005 in the Proceedings of the National Academy of Sciences (PNAS), Ramanathan and Chung, along with their colleagues at the National Center for Atmospheric Research, the University of Washington, and in India and Switzerland, found through simulations that tiny particles of air pollution called aerosols are "masking" the warming effect from greenhouse gases. "The greenhouse gases are pushing in one direction, warming the ocean and trying to make more rain, and the aerosols are pushing in another direction for cooler oceans and less rain. The net effect is to drive the monsoon rain system away from South Asia into the equatorial and southern oceans," said Ramanathan. "Some years the aerosols might win and in some years the greenhouse effect may win. So we are concerned that in coming decades the variability between the two will become large and it will be difficult to cope with rapid changes from year to year."

EDIT

http://www.terradaily.com/reports/Pollution_Greenhouse_Gases_And_Climate_Clash_In_South_Asia.html

[XemaSab]

1. I'm confused

I thought aerosols were greenhouse gasses, in addition to being ozone killers.

:shrug:

[hatrack]

2. "Aerosol" in this context means any suspended airborne particle

Such as the stuff that makes up smog, or the "Asian Brown Cloud", as they're coming to call the pall of goo that stretches from Teheran to Mumbai to Bangkok to Seoul.

[XemaSab]

3. Ah, thanks

I was thinking of the stuff in the hairspray cans... :P