If Only 19th-Century America Had Listened to a Woman ScientistHuman-induced climate change may seem a purely modern phenomenon. Even in ancient Greece, however, people understood that human activities can change climate. Later the early United States was a lab for observing this as its settlers altered nature. By 1800 it was known that the mass clearing of forests raised temperatures in the Eastern U.S. and that climatic changes followed the pioneers as they spread west.
