Rockfall activity in the Kangchenjunga area, Nepal Himalaya

Abstract Rockfall activity and related environmental factors (i.e. bedrock thermal regime and precipitation) were monitored through most of one year at elevations between 4600 m and 6800 m in the Kangchenjunga valley of the Nepal Himalaya to identify rockfall dynamics, estimate rockfall frequency fo...

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Bibliographic Details
Published in:Permafrost and Periglacial Processes
Main Authors: Regmi, Dhananjay, Watanabe, Teiji
Other Authors: Japan Science Society, Tokachi Mainichi Newspaper Co., Japan
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2009
Subjects:
Online Access:http://dx.doi.org/10.1002/ppp.664
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fppp.664
https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.664
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Summary:Abstract Rockfall activity and related environmental factors (i.e. bedrock thermal regime and precipitation) were monitored through most of one year at elevations between 4600 m and 6800 m in the Kangchenjunga valley of the Nepal Himalaya to identify rockfall dynamics, estimate rockfall frequency for different aspects, and assess temporal and spatial variations in rockfall activity. Rockfall activity on north‐facing slopes is mainly controlled by insolation relating to solar elevation and showed an abrupt increase in the pre‐monsoon season. Rockfall activity on east‐, west‐ and south‐facing slopes is controlled by the duration and effectiveness of sunshine and accumulation of snow. The north‐facing slope has a small diurnal range of rock surface temperatures and exhibits seasonal freeze‐thaw, whereas the other aspects show frequent diurnal freeze‐thaw. These differences result in seasonal rockfall activity on the north‐facing slope and the infrequent release of large debris and year‐round rockfall activity on the other aspects. Copyright © 2009 John Wiley & Sons, Ltd.