Bloomberg: The global temperature this year reached its warmest on record based on a 12-month rolling average, James Hansen, the top climate change scientist at the National Aeronautics and Space Administration, said Wednesday. The mean surface temperature in the year through April was about 1.17 degrees Fahrenheit warmer than the 1951 to 1980 mean, according to a draft paper on the website of NASA’s Goddard Institute for Space Studies. That makes it a fraction warmer than the previous peak, in …