July 3, 2013
The group’s new reportsays the decade ending in 2010 was marked by “dramatic climate and weather extremes,” such as the European heatwave of 2003, 2010 flooding in Pakistan and droughts in several regions.
The findings arrive as President Obama is seeking traction for his wide-ranging second-term climate agenda that includes new regulations on power plant emissions.
It also finds that warming has sped up over the past 40 years, noting “the decadal rate of increase in the global temperature accelerated between 1971 and 2010.”
“The global temperature increased at an average estimated rate of 0.17°C per decade during that period, while the trend over the whole period 1880–2010 was only 0.062°C per decade,” the report states.
“Furthermore, the increase of 0.21°C in the average decadal temperature from 1991–2000 to 2001–2010 is larger than the increase from 1981–1990 to 1991–2000 (+0.14°C) and larger than for any other two successive decades since the beginning of instrumental records,” the report adds.
WMO Secretary-General Michel Jarraud used the decade-scale averages to rebut climate skeptics who are increasingly calling attention to the slowdown in the rate of surface warming over the last 10 to 15 years even as greenhouse gases accumulate.
“The last decade was the warmest, by a significant margin,” he told The Associated Press. “If anything we should not talk about the plateau, we should talk about the acceleration.”
Elsewhere, the report takes stock of the nexus between climate change and extreme weather.
“While climate scientists believe that it is not yet possible to attribute individual extremes to climate change, they increasingly conclude that many recent events would have occurred in a different way — or would not have occurred at all — in the absence of climate change,” it states.
“For example, the likelihood of the 2003 European heatwave occurring was probably substantially increased by rising global temperatures,” it adds.