in the Sierra Nevada and W Great Basin Fig. 2. Cirque Rock Glacier (RGC) in

Increases in western North America temperatures have been twice the global average over the past 50 years; mountain regions experienced accelerated warming above lowland averages. The Sierra Nevada (SN), CA, lies in a Mediterranean climate where warming climates are anticipated to impose significant...

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Bibliographic Details
Main Authors: C. I. Millar, R. D. Westfall, D. L. Delany, Gibbs Canyon
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Ice
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.133.5301
http://www.fs.fed.us/psw/cirmount/meetings/agu/pdf2007/millar_westfall_poster_agu2007.pdf
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Summary:Increases in western North America temperatures have been twice the global average over the past 50 years; mountain regions experienced accelerated warming above lowland averages. The Sierra Nevada (SN), CA, lies in a Mediterranean climate where warming climates are anticipated to impose significant ecological stress on already marginal alpine habitats. For example, the American pika, Ochotona princeps, endemic to alpine talus slopes, is the first animal species to be petitioned for listing as endangered by climate change (CBD 2007). SIERRA NEVADA ROCK GLACIERS AND ROCK-ICE ROCK ICE FEATURES (RIFs ( RIFs) Although considerable research has documented rapid melting of glaciers, diminishing snowpacks, and earlier stream runoff, rock glaciers have been mostly overlooked. Modern and Pleistocene RIFs and their till are abundant in the high SN from the Tahoe Basin southward. Due to rock mantling and unique cold-air circulation patterns, RIFs in other parts of the world have been shown to be in disequilibrium with climate change, to lag in response to warming, and to retain permafrost more than 1000m below the regional levels. We propose that SN RIFs respond similarly to climate change and thus provide important and overlooked sources of water in alpine regions and refugial habitat for cold- and wetland-dependent alpine species.