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Long-term aridity changes in the western United States.
Edward R Cook1, Connie A Woodhouse, C Mark Eakin
1Lamont-Doherty Earth Observatory, Palisades, NY 10964, USA. drdendro@ldeo.columbia.edu
Science (New York, N.Y.)
|October 9, 2004
Summary
The current western US drought is severe, but historical data reveals even more extreme droughts occurred between AD 900-1300. Future warming may increase long-term aridity in western North America.
Area of Science:
- Paleoclimatology
- Climate Science
- Hydrology
Background:
- The western United States is currently facing a severe, multiyear drought.
- This drought's severity is notable within recent hydroclimatic records.
Purpose of the Study:
- To reconstruct and analyze past drought conditions in the western United States.
- To compare the current drought with historical aridity events.
Main Methods:
- Utilized gridded drought reconstructions spanning 1200 years for the western US.
- Analyzed paleoclimatic data to identify periods of elevated aridity.
Main Results:
- The current drought is less severe than an epic drought period from AD 900 to 1300.
- This earlier period of extreme aridity aligns with the Medieval Warm Period.
Conclusions:
- Elevated aridity in the western US may be a natural response to climate warming.
- Future warming trends could lead to a significant long-term increase in aridity across western North America.
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