2017 is an especially hot year, without El Niño

The world in 2017 saw some of the highest average surface temperatures ever recorded, surprising scientists who had expected sharper retreat from recent record years… What made the numbers unexpected was that last year had no El Niño, a shift in tropical Pacific weather patterns that is usually linked to record-setting heat and that contributed to record highs the previous two years. In fact, last year should have benefited from a weak version of the opposite phenomenon, La Niña, which is generally associated with lower atmospheric temperatures… The warming trend comes at a time that President Donald Trump is dialing back many climate-related regulations and policies. Last year he announced that the United States would withdraw from the 2015 Paris climate accord and repeal the Clean Power Plan, an Obama-era measure designed to reduce emissions from power plants.