In January, scientists at the National Oceanic & Atmospheric
Administration's National Climatic Data Center reported the 2006
average annual temperature for the contiguous U.S. was the warmest
on record, surpassing the previous record set in 1998. Based on
preliminary data, the 2006 annual average temperature was 55
F—two degrees higher than the 20th-century norm and 0.07
degrees higher than 1998.
U.S. and global annual temperatures now are about one degree
warmer than at the start of the 20th century, a change many
scientists attribute to greenhouse gas emissions. Warming has
increased globally since the mid-1970s at a rate about three times
faster than the century-scale trend, and the past nine years have
been among the 25 warmest years on record for the contiguous
U.S.—an unprecedented streak.
With springtime conditions in much of the U.S. this winter and
Democrats gaining control of Congress, discussion of global warming
and resulting policy challenges have a...
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