Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier
Greenland's peripheral glaciers are losing mass at an accelerated rate and are contributing significantly to sea level rise, but only a few direct observations are available. Here, we use the unique combination of high-resolution remote sensing data and direct mass balance observations to separ...
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ftcopernicus:oai:publications.copernicus.org:tcd115231 2024-09-15T18:07:42+00:00 Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier Hynek, Bernhard Binder, Daniel Citterio, Michele Larsen, Signe Hillerup Abermann, Jakob Verhoeven, Geert Ludewig, Elke Schöner, Wolfgang 2023-10-23 application/pdf https://doi.org/10.5194/tc-2023-157 https://tc.copernicus.org/preprints/tc-2023-157/ eng eng doi:10.5194/tc-2023-157 https://tc.copernicus.org/preprints/tc-2023-157/ eISSN: 1994-0424 Text 2023 ftcopernicus https://doi.org/10.5194/tc-2023-157 2024-08-28T05:24:15Z Greenland's peripheral glaciers are losing mass at an accelerated rate and are contributing significantly to sea level rise, but only a few direct observations are available. Here, we use the unique combination of high-resolution remote sensing data and direct mass balance observations to separate and quantify the contribution of a singular avalanche event to the mass balance of Freya Glacier (74.38° N, 20.82 W), a small (5.5 km², 2021) mountain glacier in Northeast Greenland. Elevation changes calculated from repeated photogrammetric surveys on 11 th –18 th August 2013 and on 28 th –31 st July 2021 range from -11 m to 18 m, with a glacier-wide mean of 1.56 + 0.10 m (0.85 + 0.20 m w.e.). Somewhat surprisingly, the geodetic mass balance over the full period of 8 years (2013/14–2020/21) is slighly positive, (0.25 + 0.21 m w.e.). A main imprint of the near decadal mass balance stems from the exceptional (2.5 standard deviations above average) winter mass balance of 2017/18 with 1.85 + 0.05 m w.e., when in addition to above average precipitation, snow avalanches affected more than one third of the glacier surface and contributed at least 0.31 m w.e. (17 %) to the total winter mass balance of 2017/18. We estimate the contribution of avalanches to the accumulated mass balance 2013/14–2020/21 as 0.55 m w.e. Without this avalanche event the 8-year mass balance would have been slightly negative, -0.30 m w.e. instead of 0.25 m w.e. Due to a gap in valid observations caused by high accumulation rates and the COVID-19 pandemic the recently reported glacier-wide annual mass balance values now turn out to have a negative bias and demand a thorough reanalysis. Finally, we speculate that the projected future warming increases the likelihood of extreme snowfall events for individual years and thus, may increase the contribution of snow avalanches to the mass balance of mountain glaciers in NE Greenland. Text glacier Greenland Copernicus Publications: E-Journals |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
Greenland's peripheral glaciers are losing mass at an accelerated rate and are contributing significantly to sea level rise, but only a few direct observations are available. Here, we use the unique combination of high-resolution remote sensing data and direct mass balance observations to separate and quantify the contribution of a singular avalanche event to the mass balance of Freya Glacier (74.38° N, 20.82 W), a small (5.5 km², 2021) mountain glacier in Northeast Greenland. Elevation changes calculated from repeated photogrammetric surveys on 11 th –18 th August 2013 and on 28 th –31 st July 2021 range from -11 m to 18 m, with a glacier-wide mean of 1.56 + 0.10 m (0.85 + 0.20 m w.e.). Somewhat surprisingly, the geodetic mass balance over the full period of 8 years (2013/14–2020/21) is slighly positive, (0.25 + 0.21 m w.e.). A main imprint of the near decadal mass balance stems from the exceptional (2.5 standard deviations above average) winter mass balance of 2017/18 with 1.85 + 0.05 m w.e., when in addition to above average precipitation, snow avalanches affected more than one third of the glacier surface and contributed at least 0.31 m w.e. (17 %) to the total winter mass balance of 2017/18. We estimate the contribution of avalanches to the accumulated mass balance 2013/14–2020/21 as 0.55 m w.e. Without this avalanche event the 8-year mass balance would have been slightly negative, -0.30 m w.e. instead of 0.25 m w.e. Due to a gap in valid observations caused by high accumulation rates and the COVID-19 pandemic the recently reported glacier-wide annual mass balance values now turn out to have a negative bias and demand a thorough reanalysis. Finally, we speculate that the projected future warming increases the likelihood of extreme snowfall events for individual years and thus, may increase the contribution of snow avalanches to the mass balance of mountain glaciers in NE Greenland. |
format |
Text |
author |
Hynek, Bernhard Binder, Daniel Citterio, Michele Larsen, Signe Hillerup Abermann, Jakob Verhoeven, Geert Ludewig, Elke Schöner, Wolfgang |
spellingShingle |
Hynek, Bernhard Binder, Daniel Citterio, Michele Larsen, Signe Hillerup Abermann, Jakob Verhoeven, Geert Ludewig, Elke Schöner, Wolfgang Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier |
author_facet |
Hynek, Bernhard Binder, Daniel Citterio, Michele Larsen, Signe Hillerup Abermann, Jakob Verhoeven, Geert Ludewig, Elke Schöner, Wolfgang |
author_sort |
Hynek, Bernhard |
title |
Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier |
title_short |
Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier |
title_full |
Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier |
title_fullStr |
Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier |
title_full_unstemmed |
Accumulation by avalanches as significant contributor to the mass balance of a High Arctic mountain glacier |
title_sort |
accumulation by avalanches as significant contributor to the mass balance of a high arctic mountain glacier |
publishDate |
2023 |
url |
https://doi.org/10.5194/tc-2023-157 https://tc.copernicus.org/preprints/tc-2023-157/ |
genre |
glacier Greenland |
genre_facet |
glacier Greenland |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-2023-157 https://tc.copernicus.org/preprints/tc-2023-157/ |
op_doi |
https://doi.org/10.5194/tc-2023-157 |
_version_ |
1810445080094310400 |