With unusually warm sea-surface temperatures over a vast expanse of the tropical Pacific dominating the winter, globally the first eight months of 2010 matched the warmest such period on record, dating to 1880.
The combined ocean-land surface temperature for Jan. 1-Aug. 31 was 58.5 Fahrenheit, according to the National Climate Data Center, putting it in a first place tie with the first eight months of 1998.
That was another year in which a strong warming event, or El Nino, had taken hold in the Pacific. Here is the climate center's global analysis.
In August Arctic sea ice was well below the 1979-2000 average and was at its second lowest level, behind 2007. By contrast, the August sea ice in the Southern Hemisphere was at its highest extent ever.
For more detailed information about worldwide ice, check out the National Snow and Ice Data Center.