By way of Metafilter (ongoing discussion there as to the reality of global warming, if you're interested).
http://www.treehugger.com/files/2010/06/2010-has-been-hottest-year-on-record-noaa.phpContinuing the trend from the previous month, NOAA reports that May, the period from March to May, and from January to May all have had the hottest combined global land and ocean surface temperatures since records began in 1880.
Temperature highlights for May 2010 include:
May's combined global land and ocean surface temperature was 0.69°C above the 20th century average of 14.8°C, with land temps being 1.04°C above the average.
Ocean temperatures were the second warmest on record, coming in behind the 1998 record, with global ocean temps being 0.55°C above the average for the past century of 16.3°C.
As can be seen in the chart above, the warmest temperature variations occurred in eastern North America, eastern Brazil, Eastern Europe, southern Asia, eastern Russia, and equatorial Africa. NOAA data shows anomalously cool conditions in western North America, northern Argentina, interior Asia, and Western Europe. Bucking the trend, Germany had its coolest May since 1991 and the 12th coolest May on record.