DOI: 10.5194/tc-8-1317-2014
Scopus记录号: 2-s2.0-84927627136
论文题名: Debris thickness of glaciers in the Everest area (Nepal Himalaya) derived from satellite imagery using a nonlinear energy balance model
作者: Rounce D ; R ; , McKinney D ; C
刊名: Cryosphere
ISSN: 19940416
出版年: 2013
卷: 8, 期: 4 起始页码: 1317
结束页码: 1329
语种: 英语
英文关键词: accuracy assessment
; energy balance
; glacial debris
; ice thickness
; image resolution
; Landsat
; nonlinearity
; pixel
; satellite imagery
; Himalayas
; Nepal
英文摘要: Debris thickness is an important characteristic of debris-covered glaciers in the Everest region of the Himalayas. The debris thickness controls the melt rates of the glaciers, which has large implications for hydrologic models, the glaciers' response to climate change, and the development of glacial lakes. Despite its importance, there is little knowledge of how the debris thickness varies over these glaciers. This paper uses an energy balance model in conjunction with Landsat7 Enhanced Thematic Mapper Plus (ETM+) satellite imagery to derive thermal resistances, which are the debris thickness divided by the thermal conductivity. Model results are reported in terms of debris thickness using an effective thermal conductivity derived from field data. The developed model accounts for the nonlinear temperature gradient in the debris cover to derive reasonable debris thicknesses. Fieldwork performed on Imja-Lhotse Shar Glacier in September 2013 was used to compare to the modeled debris thicknesses. Results indicate that accounting for the nonlinear temperature gradient is crucial. Furthermore, correcting the incoming shortwave radiation term for the effects of topography and resampling to the resolution of the thermal band's pixel is imperative to deriving reasonable debris thicknesses. Since the topographic correction is important, the model will improve with the quality of the digital elevation model (DEM). The main limitation of this work is the poor resolution (60 m) of the satellite's thermal band. The derived debris thicknesses are reasonable at this resolution, but trends related to slope and aspect are unable to be modeled on a finer scale. Nonetheless, the study finds this model derives reasonable debris thicknesses on this scale and was applied to other debris-covered glaciers in the Everest region. © Author(s) 2014. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74980
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: Center for Research in Water Resources, University of Texas at Austin, Austin, TX, United States
Recommended Citation:
Rounce D,R,, McKinney D,et al. Debris thickness of glaciers in the Everest area (Nepal Himalaya) derived from satellite imagery using a nonlinear energy balance model[J]. Cryosphere,2013-01-01,8(4)