PowerSwitch

As the world’s governments dither on climate change, data continue to stream in on the alarming rate of warming. Global surface temperatures for 2010 matched record highs, with the past decade the hottest ever recorded. Arctic ice cover continued its precipitous decline in 2010, attaining the lowest measured extent for any December on record and third lowest in summer. And the amplifying effect of this snow and ice melt is larger than previously thought, according to new research.

“The 2010 data confirm the Earth’s significant long-term warming trend,” according to World Meteorological Organization chief Michel Jarraud. “The ten warmest years on record have all occurred since 1998.”

Warming was most extreme this past year in two regions. The first covers most of Canada and Greenland, with mean temperatures for the year increasing by upwards of 3°C (5.4°F). The second region extends from northern Africa to the western portion of China, which saw increases between 1 and 3°C (1.8 and 5.4°F). Some areas experienced cooler than normal temperatures last year (e.g., northwest Europe and southeast United States), though these areas were smaller in size and the temperature changes were lower in magnitude.

Despite these regional variations, the most telling metric of climate change is the increase in global averages. Three major data sets of sea and land temperatures, when harmonized and corrected for localized conditions such as urban heat islands, show an increase of over 0.5 °C (just shy of 1°F) compared to the mean temperature for 1961-1990. When accounting for uncertainty of the measurements, 2010 temperatures matched 2005 and 1998 as the hottest since systematic measurements began in the mid-19th century.