For the U.S., 2015 is second-hottest year ever recorded

http://www.scientificamerican.com/article/december-heat-boosts-2015-to-2nd-warmest-year-in-u-s-history1/

http://www.climatecentral.org/news/december-heat-boosts-2015-to-2nd-warmest-year-for-us-19881

By Andrea Thompson, Climate Central on January 7, 2016

2015 is officially in the books as the second-hottest year ever recorded for the U.S., with a major boost provided by the incredible warmth that bathed the eastern half of the country in December, the National Oceanic and Atmospheric Administration announced Thursday.

That second-place finish comes as both NOAA and NASA are expected to announce that the year was the hottest on record globally. While that record heat was helped in part by one of the strongest El Ninos on record, it was mainly due to the contributions of manmade global warming, scientists have said.

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This was the 19th consecutive year that the overall U.S. temperature exceeded the 20th century average, NOAA said.

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And not only was December record warm, it was also record wet, the first time a month has set both records simultaneously, Crouch said.

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Four states—Florida, Montana, Oregon, and Washington—saw their all-time warmest year, while three more—Alaska, California, and Idaho—had their second warmest. (California had its record warmest year in 2014.)

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While parts of the U.S. were relatively cool at various times during the year, there were very few similar spots on the globe. Overall the planet saw incredible warmth, particularly in the oceans. El Nino helped to push Pacific Ocean temperature to levels rivaling the strongest events on record, but a Climate Central analysis showed that the overwhelming contributor to the year’s record warmth is the excess heat that has built up in Earth’s atmosphere because of the accumulation of greenhouse gases emitted by human activities.

Of the 15 warmest years on record, 14 have occurred in the 20th century. The last time there was a record cold year was 1911.

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