Discovery of 'Asian Brown Cloud'
Over Indian Ocean Sets Off Fight

LA JOLLA, Calif. -- In 1999, Indian scientist Veerabhadran Ramanathan led a team of researchers that discovered one of the largest bodies of pollution ever measured.

Using planes, ships, balloons and satellites, his multinational team of 200 scientists tracked a gritty brown blanket of soot, dust and smoke that was nearly two miles thick. It hung over an area of the Indian Ocean roughly the size of the U.S.

Quickly dubbed the "Asian Brown Cloud," the discovery opened a new frontier in atmospheric study. It suggested that man-made soot may be almost as critical a factor in causing climate change as the invisible layers of carbon dioxide and other so-called greenhouse gases emitted from power plants, factories and cars.

The study and subsequent research showed such clouds could blow thousands of miles, contributing to global warming and spreading harmful pollutants such as mercury and acid far from their point of origin. Last August a United Nations agency warned the cloud could lead to "several hundreds of thousands of premature deaths" from respiratory disease, as well as droughts and crop failures.

But now the research -- and prospects for further funding to advance it -- have been shrouded by a cloud of international squabbling.

Indian officials, angry their country was fingered as a source of the pollution, say the findings are a "scientific fraud." In February, they helped persuade the United Nations Environment Programme, or UNEP -- the same agency that warned of the cloud's dangers -- to drop further major research assistance.

Meanwhile, the cloud has injected some new thunderbolts into the rancor between the U.S. and developing nations over the causes of global warming. A Bush Administration official says discovery of the cloud bolsters the administration's controversial decision to reject the Kyoto Protocol. In that 1997 treaty designed to curb global warming, other industrial nations agreed to cut their emissions of six greenhouse gases beginning in 2008.

The U.S. argues the treaty is flawed because big developing nations such as India and China aren't included. Developing nations respond that industrialized countries first must cut their own pollutants, and that pushing research on soot-laden clouds would take the political heat off the U.S.

At the center of this scientific standoff between his adoptive U.S. home and his homeland of India is Dr. Ramanathan, a 58-year-old atmospheric scientist at the Scripps Institution of Oceanography here in La Jolla.

"My colleagues told me when I got into this that global warming is not really pure science -- politics is mixed in with it," says the slim, boyish-looking scientist. "I was always deep in my trench working on the science. Then I came out of my trench and got caught in the middle of this."

He knew about soot firsthand from growing up near Madras in India where his mother, like millions of Indian housewives, cooked with dried cow dung -- a plentiful, cheap fuel that provides a steady source of heat. Accumulated soot from the fuel blackened the walls of the family kitchen, which was kept apart from the rest of the house because of the heat. The walls "became permanent homes for the cockroaches because we could never see them," he recalls.

The dispute could slow scientific studies about how the earth's climate is changed by pollution. Such inquiries increasingly depend on international cooperation because the causes and effects of climate change transcend national boundaries. As Dr. Ramanathan learned, such broad-gauge studies also can trigger political fights when one nation or region feels unfairly singled out as a polluter by other countries.

It's not the first time soot has caused seismic shocks between politicians and scientists. Twenty years ago a group of scientists including Paul J. Crutzen, a Nobel laureate in chemistry, concluded that an all-out nuclear war between the U.S. and the Soviet Union would create "nuclear winter." They said thousands of thermonuclear blasts would create a globe-girdling cloud of soot, ash and other debris that would block out the sun, causing widespread crop failures, famine and death. Scientists, government officials and politicians debated the matter for years, until the Soviet Union collapsed.

"Fortunately, we never learned who was right," says Dr. Crutzen, who helped Dr. Ramanathan organize the Asian Brown Cloud experiment. This time he's convinced time will prove Dr. Ramanathan is right, though he and other scientists are worried that a breakdown in needed international cooperation could slow follow-up research.

Dr. Ramanathan, nicknamed "Ram," graduated from the Indian Institute of Science and came to the U.S. in the 1970s as a promising graduate student at the State University of New York at Stony Brook. He was attracted to atmospheric studies because not much scientific work had been done on the long-distance travel of pollution. One reason: It requires painstaking planning and diplomacy skills to get scientists from many nations to participate.

His colleagues consider him a patient diplomat and determined scientist. "Ram can be relentless," says Jeffrey Kiehl, a former research student of Dr. Ramanathan's. "Once he latches on to a scientific problem, he's not going to let go until he's got the answer."

Dr. Kiehl, currently a senior scientist at the National Center for Atmospheric Research in Boulder, Colo., recalls that some of Dr. Ramanathan's peers told him he probably wouldn't find much air pollution over the Indian Ocean.

Dr. Ramanathan knew better. He and Dr. Crutzen had talked for years about the need for a large-scale experiment that tracked pollution in Asia. In 1999, the financing, technology and, seemingly, the political support came together in the Indian Ocean experiment, called INDOEX for short. As chief investigator, Dr. Ramanathan recruited scientists from 15 countries, including 50 from India and one Indian research ship. He coordinated the six-week, $25 million experiment from his headquarters in the Maldives, a group of islands in the Indian Ocean, and from an instrument-crammed C-130 military transport plane that made several passes through the airborne murk.

The findings quickly turned heads in the tight-knit fraternity of atmospheric scientists. The reigning theory of "aerosols" -- particles such as soot that are suspended in the air -- was that they soon drop from the sky, leaving much of the earth's atmosphere relatively pristine. Scientists previously believed only greenhouse gases such as carbon dioxide could be carried by prevailing winds for thousands of miles from where they were emitted.

But the discovery of the cloud over the Indian Ocean, at some points more than 1,000 miles from the source of the pollution, showed aerosols also could blow long distances, changing the global climate. One of the cloud's most powerful ingredients is soot, according to Dr. Ramanathan. Because soot is dark, it warms the upper air by absorbing sunlight and artificially cools the surface of the earth. This can cause regional droughts, such as the one that has plagued India for more than a year. Among the reasons: less evaporation from the ocean because it's kept cooler -- resulting in less moisture that can fall as rain.

Asian pollution, because it contains the residue from hundreds of millions of dung-fueled cooking fires and inefficient coal furnaces, carries an unusually large burden of soot, Dr. Ramanathan says.

Subsequent research seemed to confirm his findings.

Last year, Surabit Menon, an atmospheric scientist at Columbia University, used a computer model fed with Chinese weather reports and pollution measurements. It showed emissions from coal-fired power plants and other sooty sources appear to be heating China's air, making it unstable enough to shift traditional rainfall patterns, causing more rain in the south and exacerbating a drought in the north.

Two years ago, scientists from 13 nations used planes, satellites and ships to sample plumes of pollution blowing east from China's seacoast. Hans Friedli, a senior research associate at the U.S. National Center for Atmospheric Research who was part of the team, remembers flying into the dark emissions from Beijing and Shanghai and measuring "the highest concentrations [of pollutants] that I have seen from an aircraft except when you fly into wildfires."

In addition to soot, Dr. Friedli found mercury, a poison that is released by burning coal. While China has begun to cut back on its use of coal, it still uses far more than the U.S. Mercury emissions from coal are troublesome, in part, because they tend to stay in the atmosphere for at least a year, long enough to circle the globe.

Dr. Menon's study of China's air generated a spate of e-mails from India asserting that she was unfairly blaming Asia. "People are going to be offended if they're being blamed for these aerosols, but some of it affects their region and you want to try to improve their quality of life there," says Dr. Menon, who comes from Bombay.

The U.S. also emits clouds of pollution that drift over the Atlantic and can reach Europe, she notes, but these clouds are brighter, partly because more efficient U.S. combustion processes create less soot. While the plumes from the U.S. contribute to pollution, they contribute less to global warning because the lighter clouds reflect heat back into space rather than absorbing it, as a darker cloud would, according to Dr. Menon.

India's scientists, who had known about the results of Dr. Ramanathan's study for three years, were largely silent about it until UNEP announced the Asian Brown Cloud in a London press conference last August, just before a U.N. environmental conference in South Africa. The announcement -- including suggestions that the cloud could reduce sunlight hitting the earth by as much as 15% and cut rainfall over much of Asia by up to 40% -- prompted a bevy of scary headlines such as "Giant toxic cloud threatens millions."

That got Indian politicians fired up. Indians' criticism of Dr. Ramanathan's findings has been particularly painful since it emanated from his alma mater, the Indian Institute of Science in Bangalore.

A report from the institute last October claimed the 1999 study reveals only a "hazy understanding" of the cloud's impact on weather. Moreover, the report added, the United Nations agency's description of the cloud's climate and health effects "are based more on fantasy than facts."

This February at a meeting in Nairobi, Kenya, T.R. Baalu, India's Environment and Forests minister, backed by diplomats from Pakistan and Indonesia, asked the UNEP to reject a request by Dr. Ramanathan and other scientists for more money to broaden their research to cover all of Asia. The objectors argued that, by singling out Asia, the new research would reduce the pressure the Kyoto treaty puts on Europe and the U.S. to reduce their emissions of greenhouse gases.

Asked about that, Mr. Baalu responded in a statement last week that other regions produce hazy clouds and asserted that India's plume is "a necessity" because the country has a large and poor population that must derive heat from burning dried animal dung and similar materials. There is "no conclusive evidence" that India's cloud is harmful, and it "is not an issue worth spending resources by organizations like UNEP, which should concentrate on major concerns," he said.

After the objections, further research funds were removed from UNEP's "core funding activities," says Klaus Toepfer, director of the U.N. agency. He adds that "extra budgetary funds" will be available to determine whether "this is not just an Asian phenomenon," but he declines to be more specific.

Still, says Dr. Ramanathan, "Nairobi was a setback."

It doesn't help Dr. Ramanathan in his spat with India that the U.S., which paid for half of INDOEX, is delighted with his work. James R. Mahoney, a meteorologist and assistant secretary of Commerce who coordinates overall research on climate change for the Bush Administration, says the discovery of the Asian Brown Cloud shows that the long-distance travel of airborne soot and similar pollutants may cause as much as half of the globe's artificial warming. Dr. Mahoney calls the cloud as important as the 1980s discovery of El Nino, the periodic configuration of currents in the Pacific Ocean that influences much of the planet's weather.

Following the cut in U.N. funding, the U.S. will press leaders of industrial nations and members of the next international convention on climate change -- scheduled for Milan in December -- for funds for more satellites and earth observation stations that can provide better data.

Meanwhile, Dr. Ramanathan has been pushing for a more diplomatically acceptable name for his cloud. The U.N. agency has changed it to "Atmospheric Brown Cloud."

Write to John J. Fialka john.fialka@wsj.com

Updated May 6, 2003 3:00 p.m.