Carbon Cloud Linked to ’97 Asian Wildfires

Wildfires that raged in Indonesia in 1997 charred millions of acres and spread a thick haze in the Southern Hemisphere, threatening the health of millions of people and dealing a severe blow to the region’s economy.

Now, ecologists have discovered another alarming effect: The fires may have spewed enough carbon to significantly affect the climate.

In 1997, extreme El Nino conditions triggered a drought in southeast Asia and elsewhere. Examining satellite images and using field measurements on the island of Borneo, peat-land ecologist Susan Page at the University of Leicester in England figured that about 3,000 square miles of unusually dry swamp forest and peat bogs burned.

As much as 2.6 billion tons of carbon were released into the atmosphere from that area during the fires, she said.

That’s an amount equal to 40% of the total amount of carbon released annually in the combustion of fossil fuels worldwide. Scientists believe that rising levels of carbon dioxide and other heat-trapping gases in the atmosphere play a key role in global warming.

With the wildfires’ help, she said, 1997-98 marked the world’s largest increase in carbon emissions. She said the carbon volume “came as a bit of a surprise.”

The result, she said, may push scientists and government leaders to pay closer attention to the global environmental effects of wildfires.

Page’s findings appear in the Nov. 7 issue of the journal Nature.

She said peat lands in tropical areas are likely to be a major source of carbon emissions for years unless they are protected from fire and damaging human activities, like logging.

In an accompanying commentary, David Schimel and David Baker of the National Center for Atmospheric Research in Boulder, Colo., said the findings show that the global carbon cycle can be dramatically affected by abrupt events.

“Especially in areas of high carbon density, catastrophic events affecting small areas can evidently have a huge impact on the global carbon balance,” they wrote.