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The World's Largest Floods, Past and Present: Their Causes and Magnitudes

By Jim E. O'Connor and John E. Costa


U.S. Geological Survey Circular 1254

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Floods are among the most powerful forces on earth. Human societies worldwide have lived and died with floods from the very beginning, spawning a prominent role for floods within legends, religions, and history. Inspired by such accounts, geologists, hydrologists, and historians have studied the role of floods on humanity and its supporting ecosystems, resulting in new appreciation for the many-faceted role of floods in shaping our world. Part of this appreciation stems from ongoing analysis of long-term streamflow measurements, such as those recorded by the U.S. Geological Survey's (USGS) streamflow gaging network. But the recognition of the important role of flooding in shaping our cultural and physical landscape also owes to increased understanding of the variety of mechanisms that cause floods and how the types and magnitudes of floods can vary with time and space. The USGS has contributed to this understanding through more than a century of diverse research activities on many aspects of floods, including their causes, effects, and hazards. This Circular summarizes a facet of this research by describing the causes and magnitudes of the world's largest floods, including those measured and described by modern methods in historic times, as well as floods of prehistoric times, for which the only records are those left by the floods themselves.



The Largest Floods of the Quaternary Period
Floods from Ice-Dammed Lakes
Basin-Breach Floods
Floods Related to Volcanism
Floods from Breached Landslide Dams
Ice-Jam Floods
Large Meteorological Floods
Floods, Landscapes, and Hazards
Selected References

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For more information:
Chief, Office of Surface Water
U.S. Geological Survey
Water Resources Division
12201 Sunrise Valley Drive, MS 415
Reston, VA 20192

U.S. Department of the Interior, U.S. Geological Survey
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Last modified: Wednesday, November 23 2016, 12:23:17 PM
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