These are the warmest 12-month periods on record for the contiguous United States. During the June 2011-June 2012 period, each of the 13 months ranked among the warmest third of their historical distribution for the first time in the 1895-present record. The odds of this occurring randomly is 1 in 1,594,323.
This is very interesting especially when looking at the ice reports up north. Spring came roughly 3 full weeks early this year and we had record highs in March with temps up near 90 degrees at the end of the month into April. This has now translated to the northern ice pack which just happens to be 3 full weeks ahead of the summer melt season. Coincidence? Hardly. La Nina has been replaced by El Nino. Temperatures are climbing again. Look for record numbers of boats again transitting the infamous Northwest Passage, now very much ice-free.
According to the National Snow and Ice Data Center (NSIDC), Arctic ice retreated very quickly in June. "The last three Junes (2010-2012) are the three lowest in the satellite record. June 2012 ice extent was 140,000 square kilometers (54,000 square miles) above the 2010 record low. Ice losses were notable in the Kara Sea, and in the Beaufort Sea, where a large polynya has formed. Retreat of ice in the Hudson and Baffin bays also contributed to the low June 2012 extent. The only area of the Arctic where sea ice extent is currently above average is along the eastern Greenland coast."