Indian Ocean Polluted

An area of pollution roughly the size of the continental United States has been discovered in the Indian Ocean by an international team of scientists.

Scientists working on the $25 million Indian Ocean Experiment uncovered a 4 million square mile (10.3 million square kilometer) area of polluted water, scientists at Scripps Institute of Oceanography at University of California, San Diego announced this week.

V. Ramanathan, director of the Center for Clouds, Chemistry and Climate at Scripps, said there was a brownish haze layer over the Indian Ocean almost 1,000 miles (1,600 kilometers) off the coast.

"That was what really stunned us - how pervasive these aerosols were and how they could survive at such long distances from where they originated," Ramanathan said.

Scientists from the United States, Europe, India and the Maldives set out in February for a six-week field experiment to investigate how tiny pollutant particles called aerosols move through the atmosphere, and how those aerosols affect the climate. The Indian Ocean was targeted for the study to see how monsoon winds typical of the northern hemisphere carried pollution from densely populated countries like Asia and India.

The area affected by the pollution includes the Arabian Sea, much of the Bay of Bengal and other areas in northern Indian Ocean,

"It appeared as if the whole Indian subcontinent was surrounded by a mountain of pollution," said Ramanathan, who chaired the study with Nobel laureate Paul Crutzen.

Early results of the experiment indicate that the pollutants have both a warming and a cooling effect on global climate, but scientists planned to conduct further research to determine the impact on climate processes and marine life.

Any reduction in the amount of sunlight reaching the ocean surface will have a detrimental effect on plant life that depends on photosynthesis, scientists said.

The U.S. component of the research was funded by the National Science Foundation, the U.S. Department of Energy, the National Oceanic and Atmospheric Administration and NASA.