Donald Trump has caused anger after claiming the east coast of the United States could use a bit of global warming because of its current cold spell. Individual weather events, like when it's unusually cold, do not disprove global warming. Climate, on the other hand, refers to prevailing weather conditions over a long period of time.
In fact, climate scientist Katharine Hayhoe just explained this week why the record snowfall in the lakefront city of Erie, Pa. could be explained by warmer temperatures increasing the risk of lake-effect snow.
With bitterly cold temperatures gripping much of the US, President Trump has returned to a familiar theme: Mocking global warming.
"I was elected to represent the citizens of Pittsburgh, not Paris", Trump said during his announcement of the Paris withdrawal in June.
But according to experts, 2017 is still on track to be one of the hottest years recorded globally.
And just hours before Trump tweeted, the Capital Weather Gang, the weather arm of the Washington Post, posted that the USA will be the coldest region in the world "relative to normal" over the next week. And in December 2013 he was in a "freezing" Los Angeles, prompting him to say "Global warming is a total, and very expensive, hoax!" "Man, we could use a big fat dose of global warming!".