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Article: Global Warming and the Hydrologic Cycle
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- Water:Science and Issues
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CopyrightCOPYRIGHT 2003 The Gale Group Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Global Warming and the Hydrologic Cycle
To maintain the global water balance, evaporation from oceans worldwide must be balanced by precipitation into the oceans plus runoff from the continents. Earth's atmosphere contains only 0.001 percent of the Earth's water, yet it is an essential component of the global hydrologic cycle: currents of air carry water vapor over land, and the resulting precipitation enables life on land.
Increasing atmospheric concentrations of
greenhouse gases
, mainly carbon dioxide, have led to a warming at the surface, by nearly 0.6
°
C (1.0
°
F) during the twentieth century, and it is widely believed that this trend will continue in the twenty-first ...