Clouding The Issue

Climate Change: A new study indicates that poor Asians burning dung for energy may be a major cause of global warming. It may explain why glaciers are really melting -- and why climate is more complicated than some think.

It used to be a straight-line theory based on easily connected dots. The Earth was warming due to increased levels of carbon dioxide generated by man, his factories, power plants and vehicles. The U.S. and the industrialized world had to drastically reduce its CO2 levels to prevent the poles from melting and the seas from rising.

But a new study in the Aug. 2 issue of the British science journal Nature suggests that the absence of technology, not its reckless use, may be a major factor in raising the Earth's global temperature.

The haze of pollution called the "Asian Brown Cloud," caused by wood and dung burned for fuel, may be doing more harm than the tailpipes of our SUVs.

Researchers led by Veerabhadran Ramanathan, a professor of atmospheric sciences at Scripps Institute of Oceanography in California, launched three unmanned aircraft last March from the Maldives island of Hanimadhoo to fly through the Brown Cloud at various altitudes.

A total of 18 missions were flown to explore the blanket of soot, dust and smoke that at times is two miles thick and covers an area about the size of the U.S.

They found that the cloud of soot and particulate matter boosted the effect of solar heating on the surrounding air by as much as 50%.

"These findings might seem to contradict the general notion of aerosol particulates as cooling agents in the global climate system ... ." concluded the Nature article summing up the study. Dang. Just when we thought the science of global warming was settled.

These findings also may help to explain the rapid melting among the 46,000 glaciers on the Tibetan Plateau and why the Himalayan glaciers have been retreating since at least 1780.

This phenomenon also might help explain why carbon dioxide emissions and global temperatures don't track very well, if at all.

The Asian Brown Cloud was first discovered by Ramanathan in 1999. He had grown up near Madras, India, where his mother, like millions of other Indian homemakers, cooked with dried cow dung -- a plentiful, and renewable, source of cheap fuel that was a good source of heat. One might call it the earliest form of biofuel.

Such pollution, because it contains the residue from hundreds of millions of dung-fueled cooking fires and inefficient wood and coal furnaces, carries an unusually large amount of soot.

It previously had been assumed that such particulate matter, like that from volcanic eruptions, had a cooling effect on the Earth. Guess not -- at least not all the time.

A computer simulation run by Surabit Menon, an atmospheric scientist at Columbia University, using Chinese weather reports calculated the warming effects of the cloud. Menon found the brown cloud as it spread around the globe contributed more to global warming than Western greenhouse gas emissions.

S. Fred Singer, professor emeritus of environmental sciences at the University of Virginia, finds it "ironic that much of (this) pollution could be avoided by the use of cleaner fossil fuels, like gas, oil, and even coal, all of which release CO2."

Ramanathan has found some resistance to his discovery and its conclusions.

"My colleagues warned me when I got into this that global warming is not really pure science -- politics is mixed in with it." An inconvenient truth for a dedicated scientist.

India, of course, is exempt from the Kyoto Protocol as a "developing" nation. It's not that easy to put a catalytic converter on a cow. Then there's the politics of the issue. It's easier to blame a soccer mom in her SUV than an Indian family struggling to get through the day.