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Glaciers and Perennial Snowfields of the U.S. Cordillera

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Global Land Ice Measurements from Space

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Abstract

Of more than 8,000 glaciers and perennial snow-fields on 21 mountain ranges in the western U.S. (excluding Alaska), only 120 are larger than 1 km2, and just one exceeds 10 km2. Where changes in size are known, the overwhelming majority of glaciers are shrinking. There are a few that are growing. These changes, with a few exceptions that relate mainly to rock debris abundances on the glaciers, are due overwhelmingly to climate change, though it is a complex relationship. Analysis of ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery has been used in special case studies, along with published field data, to track changes in debris loads of glaciers on Mt. Rainier, show the effects of a lahar from Mt. Rainier, and track the continued shrinkage of Grinnell Glacier in Glacier National Park. The response time of glaciers in the region varies from under a decade to over a century. Blue Glacier (Olympic Mountains) is a fast responder; its length, area, and volume fluctuation history indicates that it is responding to decadal climate fluctuations as well as local long-term warming in the 20th and 21st centuries, which is probably related to greenhouse gas-driven global warming.

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Acknowledgments

ASTER data courtesy of NASA/GSFC/METI/Japan Space Systems, the U.S./Japan ASTER Science Team, and the GLIMS project. MODIS/ASTER (MASTER) airborne simulator data courtesy of NASA/Airborne Sensor Facility at Ames Research Center/Jet Propulsion Laboratory, and the EROS Data Center.

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Authors and Affiliations

  1. Department of Geology, Portland State University Portland, Portland, OR, USA

    Andrew G. Fountain, Hassan J. Basagic IV, Charles Cannon, Kristina Thorneykroft & Steve Wilson

  2. Department of Geography, Michigan State University, East Lansing, MI, USA

    Mark Devisser

  3. Los Alamos National Laboratory, Los Alamos, NM, USA

    Matthew J. Hoffman

  4. Department of Hydrology & Water Resources, College of Science, School of Earth & Environmental Sciences, The University of Arizona, Tucson, AZ, USA

    Jeffrey S. Kargel

  5. National Snow & Ice Data Center, University of Colorado, Boulder, CO, USA

    Jeffrey S. Kargel

  6. Department of Hydrology & Water Resources, University of Arizona, Tucson, AZ, USA

    Gregory J. Leonard

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  1. Andrew G. Fountain
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Correspondence to Jeffrey S. Kargel .

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Editors and Affiliations

  1. University of Arizona Dept. Hydrology & Water Resources, Tucson, Arizona, USA

    Jeffrey S. Kargel

  2. Dept. Hydrology and Water Resources, Global Land Ice Measurements from Space University of Arizona, Tuscon, Arizona, USA

    Gregory J. Leonard

  3. Texas A & M University Department of Geography, College Station, Texas, USA

    Michael P. Bishop

  4. University of Oslo Dept. Geosciences, Oslo, Norway

    Andreas Kääb

  5. University of Colorado, Boulder, Boulder, Colorado, USA

    Bruce H. Raup

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Fountain, A.G. et al. (2014). Glaciers and Perennial Snowfields of the U.S. Cordillera. In: Kargel, J., Leonard, G., Bishop, M., Kääb, A., Raup, B. (eds) Global Land Ice Measurements from Space. Springer Praxis Books(). Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-79818-7_17

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