DOI: 10.5194/tc-8-41-2014
Scopus记录号: 2-s2.0-84891881550
论文题名: Lidar snow cover studies on glaciers in the Ötztal Alps (Austria): Comparison with snow depths calculated from GPR measurements
作者: Helfricht K ; , Kuhn M ; , Keuschnig M ; , Heilig A
刊名: Cryosphere
ISSN: 19940416
出版年: 2014
卷: 8, 期: 1 起始页码: 41
结束页码: 57
语种: 英语
英文关键词: ablation
; alpine environment
; calibration
; elevation
; firn
; ground penetrating radar
; hydrometeorology
; ice flow
; Landsat thematic mapper
; laser
; lidar
; precipitation (climatology)
; snow accumulation
; snow cover
; spatial distribution
; terrain
; water storage
; Alps
; Austria
; Central Alps
; Otztal Alps
英文摘要: The storage of water within the seasonal snow cover is a substantial source of runoff in high mountain catchments. Information about the spatial distribution of snow accumulation is necessary for calibration and validation of hydro-meteorological models. Generally, only a small number of precipitation measurements deliver precipitation input for modelling in mountain areas. The spatial interpolation and extrapolation of measurements of precipitation is still difficult. Multi-temporal application of lidar techniques from aircraft, so-called airborne laser scanning (ALS), provides surface elevations changes even in inaccessible terrain. These ALS surface elevation changes can be used to derive changes in snow depths of the mountain snow cover for seasonal or subseasonal time periods. However, since glacier surfaces are not static over time, ablation, densification of snow, densification of firn and ice flow contribute to surface elevation changes. ALS-derived surface elevation changes were compared to snow depths derived from 35.4 km of ground penetrating radar (GPR) profiles on four glaciers. With this combination of two different data acquisitions, it is possible to evaluate the effect of the summation of these processes on ALS-derived snow depth maps in the high alpine region of the Ötztal Alps (Austria). A Landsat 5 Thematic Mapper image was used to distinguish between snow covered area and bare ice areas of the glaciers at the end of the ablation season. In typical accumulation areas, ALS surface elevation changes differ from snow depths calculated from GPR measurements by -0.4 m on average with a mean standard deviation of 0.34 m. Differences between ALS surface elevation changes and GPR derived snow depths are small along the profiles conducted in areas of bare ice. In these areas, the mean absolute difference of ALS surface elevation changes and GPR snow depths is 0.004 m with a standard deviation of 0.27 m. This study presents a systematic approach to analyze deviations from ALS generated snow depth maps to ground truth measurements on four different glaciers. We could show that ALS can be an important and reliable data source for the spatial distribution of snow depths for most parts of the here investigated glaciers. However, within accumulation areas, just utilizing ALS data may lead to systematic underestimation of total snow depth distribution. © 2014 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74906
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: AlpS Andndash-Centre for Climate Change Adaptation, Grabenweg 68, 6020 Innsbruck, Austria; Institute of Meteorology and Geophysics, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria; Department of Geography and Geology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria; Commission for Geodesy and Glaciology, Bavarian Academy of Sciences and Humanities, Alfons-Goppel-Str. 11, 80539 Munich, Germany; Institute of Environmental Physics, University of Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany
Recommended Citation:
Helfricht K,, Kuhn M,, Keuschnig M,et al. Lidar snow cover studies on glaciers in the Ötztal Alps (Austria): Comparison with snow depths calculated from GPR measurements[J]. Cryosphere,2014-01-01,8(1)