Cleaner air to worsen droughts in Amazon: study

Agence France-Presse: Curbing a notorious form of industrial pollution may ironically harm Amazonia, one of the world's natural treasures and a key buffer against global warming, a study released Wednesday has found. Its authors see a strong link between a decrease in sulphur dioxide emissions from coal-fired power plants and a rise in sea temperature in the northern Atlantic that was blamed for wreaking a devastating drought in western Amazonia in 2005.

University of Exeter professor Peter Cox and colleagues created a computer model to simulate the impact of aerosols -- airborne particles that, like sulphur dioxide, are also spewed out by fossil-fuel power plants -- on Amazonia's climate. The aerosols, while a bad pollutant, indirectly ease the problem of global warming as they reflect sunlight, making it bounce back into space rather than warm the Earth's surface.

In the 1970s and 1980s, according to Cox's model, high concentrations of aerosols over the highly industrialised northern hemisphere had the effect of buffering the impact of global warming on north Atlantic surface waters, which led to more rain over Amazonia. But tighter curbs on sulphur dioxide emissions from power plants led to a reduction in aerosol levels, causing these Atlantic waters to warm. This changed patterns of precipitation, leading to the 2005 drought….

Poster for Werner Herzog's film, Fitzcarraldo, which takes place in the Amazon near Manaus