Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys
There is significant uncertainty regarding the spatiotemporal distribution of seasonal snow on glaciers, despite being a fundamental component of glacier mass balance. To address this knowledge gap, we collected repeat, spatially extensive high-frequency ground-penetrating radar (GPR) observations o...
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ftdoajarticles:oai:doaj.org/article:8b07671c194646f782d269869220f4e4 2023-05-15T16:20:29+02:00 Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys D. McGrath L. Sass S. O'Neel C. McNeil S. G. Candela E. H. Baker H.-P. Marshall 2018-11-01T00:00:00Z https://doi.org/10.5194/tc-12-3617-2018 https://doaj.org/article/8b07671c194646f782d269869220f4e4 EN eng Copernicus Publications https://www.the-cryosphere.net/12/3617/2018/tc-12-3617-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-3617-2018 1994-0416 1994-0424 https://doaj.org/article/8b07671c194646f782d269869220f4e4 The Cryosphere, Vol 12, Pp 3617-3633 (2018) Environmental sciences GE1-350 Geology QE1-996.5 article 2018 ftdoajarticles https://doi.org/10.5194/tc-12-3617-2018 2022-12-31T12:38:30Z There is significant uncertainty regarding the spatiotemporal distribution of seasonal snow on glaciers, despite being a fundamental component of glacier mass balance. To address this knowledge gap, we collected repeat, spatially extensive high-frequency ground-penetrating radar (GPR) observations on two glaciers in Alaska during the spring of 5 consecutive years. GPR measurements showed steep snow water equivalent (SWE) elevation gradients at both sites; continental Gulkana Glacier's SWE gradient averaged 115 mm 100 m −1 and maritime Wolverine Glacier's gradient averaged 440 mm 100 m −1 (over > 1000 m). We extrapolated GPR point observations across the glacier surface using terrain parameters derived from digital elevation models as predictor variables in two statistical models (stepwise multivariable linear regression and regression trees). Elevation and proxies for wind redistribution had the greatest explanatory power, and exhibited relatively time-constant coefficients over the study period. Both statistical models yielded comparable estimates of glacier-wide average SWE (1 % average difference at Gulkana, 4 % average difference at Wolverine), although the spatial distributions produced by the models diverged in unsampled regions of the glacier, particularly at Wolverine. In total, six different methods for estimating the glacier-wide winter balance average agreed within ±11 %. We assessed interannual variability in the spatial pattern of snow accumulation predicted by the statistical models using two quantitative metrics. Both glaciers exhibited a high degree of temporal stability, with ∼85 % of the glacier area experiencing less than 25 % normalized absolute variability over this 5-year interval. We found SWE at a sparse network (3 stakes per glacier) of long-term glaciological stake sites to be highly correlated with the GPR-derived glacier-wide average. We estimate that interannual variability in the spatial pattern of winter SWE accumulation is only a small component (4 %–10 % of glacier-wide ... Article in Journal/Newspaper glacier glaciers The Cryosphere Alaska Directory of Open Access Journals: DOAJ Articles The Cryosphere 12 11 3617 3633 |
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Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 D. McGrath L. Sass S. O'Neel C. McNeil S. G. Candela E. H. Baker H.-P. Marshall Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
There is significant uncertainty regarding the spatiotemporal distribution of seasonal snow on glaciers, despite being a fundamental component of glacier mass balance. To address this knowledge gap, we collected repeat, spatially extensive high-frequency ground-penetrating radar (GPR) observations on two glaciers in Alaska during the spring of 5 consecutive years. GPR measurements showed steep snow water equivalent (SWE) elevation gradients at both sites; continental Gulkana Glacier's SWE gradient averaged 115 mm 100 m −1 and maritime Wolverine Glacier's gradient averaged 440 mm 100 m −1 (over > 1000 m). We extrapolated GPR point observations across the glacier surface using terrain parameters derived from digital elevation models as predictor variables in two statistical models (stepwise multivariable linear regression and regression trees). Elevation and proxies for wind redistribution had the greatest explanatory power, and exhibited relatively time-constant coefficients over the study period. Both statistical models yielded comparable estimates of glacier-wide average SWE (1 % average difference at Gulkana, 4 % average difference at Wolverine), although the spatial distributions produced by the models diverged in unsampled regions of the glacier, particularly at Wolverine. In total, six different methods for estimating the glacier-wide winter balance average agreed within ±11 %. We assessed interannual variability in the spatial pattern of snow accumulation predicted by the statistical models using two quantitative metrics. Both glaciers exhibited a high degree of temporal stability, with ∼85 % of the glacier area experiencing less than 25 % normalized absolute variability over this 5-year interval. We found SWE at a sparse network (3 stakes per glacier) of long-term glaciological stake sites to be highly correlated with the GPR-derived glacier-wide average. We estimate that interannual variability in the spatial pattern of winter SWE accumulation is only a small component (4 %–10 % of glacier-wide ... |
format |
Article in Journal/Newspaper |
author |
D. McGrath L. Sass S. O'Neel C. McNeil S. G. Candela E. H. Baker H.-P. Marshall |
author_facet |
D. McGrath L. Sass S. O'Neel C. McNeil S. G. Candela E. H. Baker H.-P. Marshall |
author_sort |
D. McGrath |
title |
Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
title_short |
Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
title_full |
Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
title_fullStr |
Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
title_full_unstemmed |
Interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
title_sort |
interannual snow accumulation variability on glaciers derived from repeat, spatially extensive ground-penetrating radar surveys |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-3617-2018 https://doaj.org/article/8b07671c194646f782d269869220f4e4 |
genre |
glacier glaciers The Cryosphere Alaska |
genre_facet |
glacier glaciers The Cryosphere Alaska |
op_source |
The Cryosphere, Vol 12, Pp 3617-3633 (2018) |
op_relation |
https://www.the-cryosphere.net/12/3617/2018/tc-12-3617-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-3617-2018 1994-0416 1994-0424 https://doaj.org/article/8b07671c194646f782d269869220f4e4 |
op_doi |
https://doi.org/10.5194/tc-12-3617-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
11 |
container_start_page |
3617 |
op_container_end_page |
3633 |
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1766008408462327808 |