el niño has now ended, and climate scientists almost universally expect 2017 to be cooler than the year before. but the scale of the heat burst has been startling to many of the experts, and some of them fear an accelerated era of global warming could be at hand over the next few years.  even at current temperatures, billions of tons of land ice are melting or sliding into the ocean. the sea is also absorbing most of the heat trapped by human emissions. those factors are causing the ocean to rise at what appears to be an accelerating pace, and coastal communities in the united states are beginning to spend billions to fight increased tidal flooding. their pleas for help from congress have largely been ignored.  the finding that a record had been set for the third year in a row was released on wednesday by three government agencies, two of them american and one british, that track measurements made by ships, buoys and land-based weather stations. they analyze the figures to correct for known problems, producing an annual average temperature for the surface of the earth. the national meteorological agency of japan confirmed the findings in a preliminary analysis.  in the british data set, 2016 set a record by only a small amount; the margin was larger in the noaa data set and larger still in nasa’s. nasa does more work than the other groups to take full account of arctic temperatures, and several scientists said they believed the nasa record to be the most accurate for 2016 for that reason.
earth sets a temperature record for the third straight year