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Global Warming Brings Earlier Spring Flowers

Walden Pond has seen warmer temperatures and earlier spring flowerings since Henry David Thoreau first stayed there in 1852.

Biggest heat spike in history

August 5, 2012

An analysis by a top government scientist says the extreme heat and drought seen in the U.S., Europe and other regions in recent years must be global warming. A new study looking at 11,000 years of climate temperatures shows the

world in the middle of a dramatic U-turn, lurching from near-record

cooling to a heat spike.