 We're going to have to be really aggressive about decarbonization, but the fact remains that a certain amount of global warming is already unfortunately baked in, and we're going to have to deal with the consequences of that. Extreme heat in New York City alone is estimated to kill about 350 people per year. He says while there is no silver bullet that will fix extreme weather events, the new goal should be keeping global warming below 2 degrees Celsius.