/ 4 July 2013

Global climate: Last decade warmest on record

Global Climate: Last Decade Warmest On Record

The World Meteorological Society has released its report on the global climate in the last decade. The body, the United Nations's agency tasked with looking at the world's climate, said 2001 to 2010 was the "decade of extremes".

In this decade the planet "experienced unprecedented high-impact climate extremes”, it said. Nine of the 10 warmest years on record happened in this time. The world average temperature was 0.88C higher than a century ago. Africa was 0.7C warmer, with every year in the decade being warmer than the average.   

Michel Jarraud, the society's secretary general, said, “The first decade of the 21st century was the warmest decade recorded since modern measurements began in 1950.” It was also marked by dramatic climate and weather extremes.

The resulting changes were being felt across the entire planetary system. Global sea levels are 20cm higher than in 1880, with glaciers losing more mass than in any previous decade. If this continued, the melting of ice sheets would contribute more to sea-level rises in this century, it said.  

2010 was the wettest year ever recorded at a global level, with southern Africa being wetter than usual. 

The frequency of large-scale climate events like tropical cyclones was also trending upward, it said. 

The report said natural factors were responsible for part of the change, but "the rapid changes that have occured have been caused largely by humanity's emissions of greenhouse gases into the atmosphere". 

And while natural variations in the climate would sent temperatures up and down over time, "human-caused change is trending in just one direction". 

Concentrations of carbon dioxide in the atmosphere recently passed 400 parts per million – a number which locks humanity into an average 2C temperature increase in the coming century. But with little slow down in emissions, temperatures by the end of the century could increase by 6C.