論文

査読有り
2019年10月

Contrasting thinning patterns between lake- and land-terminating glaciers in the Bhutanese Himalaya

CRYOSPHERE
  • Tsutaki, Shun
  • ,
  • Fujita, Koji
  • ,
  • Nuimura, Takayuki
  • ,
  • Sakai, Akiko
  • ,
  • Sugiyama, Shin
  • ,
  • Komori, Jiro
  • ,
  • Tshering, Phuntsho

13
10
開始ページ
2733
終了ページ
2750
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.5194/tc-13-2733-2019
出版者・発行元
COPERNICUS GESELLSCHAFT MBH

Despite the importance of glacial lake development in ice dynamics and glacier thinning, in situ and satellite-based measurements from lake-terminating glaciers are sparse in the Bhutanese Himalaya, where a number of proglacial lakes exist. We acquired in situ and satellite-based observations across lake- and land-terminating debris-covered glaciers in the Lunana region, Bhutanese Himalaya. A repeated differential global positioning system survey reveals that thickness change of the debris-covered ablation area of the lake-terminating Lugge Glacier (-4.67 +/- 0.07 m a(-1)) is more than 3 times more negative than that of the land-terminating Thorthormi Glacier (-1 40 +/- 0.07 m a(-1)) for the 2004-2011 period. The surface flow velocities decrease down-glacier along Thorthormi Glacier, whereas they increase from the upper part of the ablation area to the terminus of Lugge Glacier. Numerical experiments using a two-dimensional ice flow model demonstrate that the rapid thinning of Lugge Glacier is driven by both a negative surface mass balance and dynamically induced ice thinning. However, the thinning of Thorthormi Glacier is minimised by a longitudinally compressive flow regime. Multiple supraglacial ponds on Thorthormi Glacier have been expanding since 2000 and have merged into a single proglacial lake, with the glacier terminus detaching from its terminal moraine in 2011. Numerical experiments suggest that the thinning of Thorthormi Glacier will accelerate with continued proglacial lake development.


リンク情報
DOI
https://doi.org/10.5194/tc-13-2733-2019
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000492037500001&DestApp=WOS_CPL