End-of-winter snow depth variability on glaciers in Alaska
A quantitative understanding of snow thickness and snow water equivalent (SWE) on glaciers is essential to a wide range of scientific and resource management topics. However, robust SWE estimates are observationally challenging, in part because SWE can vary abruptly over short distances in complex t...
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ftunivnebraskali:oai:digitalcommons.unl.edu:usgsstaffpub-1875 2023-11-12T04:17:35+01:00 End-of-winter snow depth variability on glaciers in Alaska McGrath, Daniel Sass, Louis O/Neel, Shad Arendt, Anthony Wolken, Gabriel Gusmeroli, Alessio Kienholz, Christian McNeil, Christopher 2015-01-01T08:00:00Z application/pdf https://digitalcommons.unl.edu/usgsstaffpub/865 https://digitalcommons.unl.edu/context/usgsstaffpub/article/1875/viewcontent/McGrath_et_al_2015_Journal_of_Geophysical_Research__Earth_Surface.pdf unknown DigitalCommons@University of Nebraska - Lincoln https://digitalcommons.unl.edu/usgsstaffpub/865 https://digitalcommons.unl.edu/context/usgsstaffpub/article/1875/viewcontent/McGrath_et_al_2015_Journal_of_Geophysical_Research__Earth_Surface.pdf USGS Staff -- Published Research text 2015 ftunivnebraskali 2023-10-30T11:21:54Z A quantitative understanding of snow thickness and snow water equivalent (SWE) on glaciers is essential to a wide range of scientific and resource management topics. However, robust SWE estimates are observationally challenging, in part because SWE can vary abruptly over short distances in complex terrain due to interactions between topography and meteorological processes. In spring 2013, we measured snow accumulation on several glaciers around the Gulf of Alaska using both ground- and helicopter-based ground-penetrating radar surveys, complemented by extensive ground truth observations. We found that SWE can be highly variable (40% difference) over short spatial scales (tens to hundreds of meters), especially in the ablation zone where the underlying ice surfaces are typically rough. Elevation provides the dominant basin-scale influence on SWE, with gradients ranging from 115 to 400 mm/100 m. Regionally, total accumulation and the accumulation gradient are strongly controlled by a glacier’s distance from the coastal moisture source. Multiple linear regressions, used to calculate distributed SWE fields, show that robust results require adequate sampling of the true distribution of multiple terrain parameters. Final SWE estimates (comparable to winter balances) show reasonable agreement with both the Parameter-elevation Relationships on Independent Slopes Model climate data set (9–36% difference) and the U.S. Geological Survey Alaska Benchmark Glaciers (6–36% difference). All the glaciers in our study exhibit substantial sensitivity to changing snow-rain fractions, regardless of their location in a coastal or continental climate. While process-based SWE projections remain elusive, the collection of ground-penetrating radar (GPR)-derived data sets provides a greatly enhanced perspective on the spatial distribution of SWE and will pave the way for future work that may eventually allow such projections. Text glaciers Alaska University of Nebraska-Lincoln: DigitalCommons@UNL Gulf of Alaska |
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University of Nebraska-Lincoln: DigitalCommons@UNL |
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ftunivnebraskali |
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A quantitative understanding of snow thickness and snow water equivalent (SWE) on glaciers is essential to a wide range of scientific and resource management topics. However, robust SWE estimates are observationally challenging, in part because SWE can vary abruptly over short distances in complex terrain due to interactions between topography and meteorological processes. In spring 2013, we measured snow accumulation on several glaciers around the Gulf of Alaska using both ground- and helicopter-based ground-penetrating radar surveys, complemented by extensive ground truth observations. We found that SWE can be highly variable (40% difference) over short spatial scales (tens to hundreds of meters), especially in the ablation zone where the underlying ice surfaces are typically rough. Elevation provides the dominant basin-scale influence on SWE, with gradients ranging from 115 to 400 mm/100 m. Regionally, total accumulation and the accumulation gradient are strongly controlled by a glacier’s distance from the coastal moisture source. Multiple linear regressions, used to calculate distributed SWE fields, show that robust results require adequate sampling of the true distribution of multiple terrain parameters. Final SWE estimates (comparable to winter balances) show reasonable agreement with both the Parameter-elevation Relationships on Independent Slopes Model climate data set (9–36% difference) and the U.S. Geological Survey Alaska Benchmark Glaciers (6–36% difference). All the glaciers in our study exhibit substantial sensitivity to changing snow-rain fractions, regardless of their location in a coastal or continental climate. While process-based SWE projections remain elusive, the collection of ground-penetrating radar (GPR)-derived data sets provides a greatly enhanced perspective on the spatial distribution of SWE and will pave the way for future work that may eventually allow such projections. |
format |
Text |
author |
McGrath, Daniel Sass, Louis O/Neel, Shad Arendt, Anthony Wolken, Gabriel Gusmeroli, Alessio Kienholz, Christian McNeil, Christopher |
spellingShingle |
McGrath, Daniel Sass, Louis O/Neel, Shad Arendt, Anthony Wolken, Gabriel Gusmeroli, Alessio Kienholz, Christian McNeil, Christopher End-of-winter snow depth variability on glaciers in Alaska |
author_facet |
McGrath, Daniel Sass, Louis O/Neel, Shad Arendt, Anthony Wolken, Gabriel Gusmeroli, Alessio Kienholz, Christian McNeil, Christopher |
author_sort |
McGrath, Daniel |
title |
End-of-winter snow depth variability on glaciers in Alaska |
title_short |
End-of-winter snow depth variability on glaciers in Alaska |
title_full |
End-of-winter snow depth variability on glaciers in Alaska |
title_fullStr |
End-of-winter snow depth variability on glaciers in Alaska |
title_full_unstemmed |
End-of-winter snow depth variability on glaciers in Alaska |
title_sort |
end-of-winter snow depth variability on glaciers in alaska |
publisher |
DigitalCommons@University of Nebraska - Lincoln |
publishDate |
2015 |
url |
https://digitalcommons.unl.edu/usgsstaffpub/865 https://digitalcommons.unl.edu/context/usgsstaffpub/article/1875/viewcontent/McGrath_et_al_2015_Journal_of_Geophysical_Research__Earth_Surface.pdf |
geographic |
Gulf of Alaska |
geographic_facet |
Gulf of Alaska |
genre |
glaciers Alaska |
genre_facet |
glaciers Alaska |
op_source |
USGS Staff -- Published Research |
op_relation |
https://digitalcommons.unl.edu/usgsstaffpub/865 https://digitalcommons.unl.edu/context/usgsstaffpub/article/1875/viewcontent/McGrath_et_al_2015_Journal_of_Geophysical_Research__Earth_Surface.pdf |
_version_ |
1782334405557092352 |