Extreme weather fuels debate over global warming

Anne Chaon in Agence France-Presse: As Russia battles wildfires triggered by an unprecedented heatwave, flood waters surge across a drenched Pakistan leaving millions of people homeless, and questions are asked about global warming. Extreme weather has been a feature of the summer of 2010, with floods in Pakistan, China and Eastern Europe seemingly matched by heatwaves in Western Europe and Russia.

However, experts interviewed by AFP Monday were cautious over offering the events as proof of a changing climate, saying that while they fit with climatic projections in a warming planet, one extremely dry -- or wet -- summer isn't sufficient evidence in isolation.

"One cannot conclude 100 percent that nothing like this has happened in the past 200 years, but the suspicion is there. Even if it's only a suspicion," said Jean-Pascal van Ypersele, vice-president of the Intergovernmental Panel on Climate Change (IPCC), which has tracked the impact of human activity on climate for the past 20 years. "These are events which reproduce and intensify in a climate disturbed by greenhouse gas pollution," he said. "Extreme events are one of the ways in which climatic changes become dramatically visible."

The planet has never been as hot as it has been in the first half of this year, the US National Oceanic and Atmospheric Administration said in a July report. According to the IPCC, droughts and heatwaves likes those affecting Russia and 18 US states become longer and more intense in a warming planet.

"Whether in frequency or intensity, virtually every year has broken records, and sometimes several times in a week," said Omar Baddour, who tracks climate change for the World Meteorological Organisation….

Mammatus storm clouds over San Antonio, Texas, shot by Derrich, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license