Hurricane breeding grounds in the Atlantic and Pacific oceans are being warmed by greenhouse gases, raising fears that more intense and devastating storms will be unleashed on nearby coastlines, scientists warned last week.
Climate researchers found that emissions from burning fossil fuels and other industrial activities were to blame for driving temperatures upwards in tropical waters, where hurricanes form. If sea temperatures continue to rise, scientists fear that category four and five hurricanes, such as Katrina, which battered New Orleans last year, will become more commonplace.
The scientists, led by Ben Santer at Lawrence Livermore National Laboratory in California, used 22 climate models to investigate the possible causes of a rise in sea surface temperatures of up to 0,67 degrees Celsius in the Atlantic and Pacific tropics from 1906 to 2005. Each computer model was run several times to work out how much sea surface temperatures would have warmed with and without rising levels of greenhouse gases and other pollutants.
They found that tiny particulates from volcanos and sulphates from industrial plants blocked the sun, and so cooled the oceans. But the effect was swamped by the rise in greenhouse gases, which led to warmer oceans.
The study appears in the latest issue of Proceedings of the National Academy of Sciences.
Nathan Gillett, a co-author of the study at the climatic research unit of the University of East Anglia, said: ”We know the oceans have been warming in these regions and some scientists have said it was because of natural events. But this study confirms it cannot be explained by a natural cycle.” — Â