Rising temperatures, shorter winters and an increase in emissions from fossil fuels have all contributed to the reclassification of New York City from a humid continental climate to a subtropical one, according to the National Climate Assessment. To be subtropical, summers must average above 72 degrees Fahrenheit and winters to stay above 27 degrees Fahrenheit which New York City has met for the last five years. New species of trees and insects showing up in the Metro area were the first clue that the climate had changed.
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