Surface-elevation changes and mass balance of the Academy of Sciences Ice Cap, Severnaya Zemlya
We have determined the surface-elevation change rates of the Academy of Sciences Ice Cap, Severnaya Zemlya, Russian Arctic, for two different periods: 2004–2016 and 2012/2013–2016. The former was calculated from differencing of ICESat and ArcticDEM digital elevation models, while the latter was obta...
Published in: | Ice and Snow |
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Main Authors: | , , , , |
Other Authors: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
IGRAS
2020
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Subjects: | |
Online Access: | https://ice-snow.igras.ru/jour/article/view/781 https://doi.org/10.31857/S2076673420010021 |
Summary: | We have determined the surface-elevation change rates of the Academy of Sciences Ice Cap, Severnaya Zemlya, Russian Arctic, for two different periods: 2004–2016 and 2012/2013–2016. The former was calculated from differencing of ICESat and ArcticDEM digital elevation models, while the latter was obtained by differencing two sets of ArcticDEM digital elevation models. From these surface-elevation change rates we obtained the geodetic mass balance, which was nearly identical for both periods, at −1,72±0,67 Gt a−1, equivalent to −0,31±0,12 m w.e. a−1 over the whole ice cap area. Using an independent estimate of frontal ablation for 2016−2017 of −1,93±0,12 Gt a−1 (−0,31±0,12 m w.e. a−1), we get an estimate of the climatic mass balance not significantly different from zero, at 0,21±0,68 Gt a−1 (0,04±0,13 m w.e. a−1), which agrees with the near-zero average balance at a decadal scale observed during the last four decades. Making an observationally-based assumption on accumulation rate, we estimate the current total ablation from the ice cap, and its partitioning between frontal ablation, dominated by calving (~54%) and climatic mass balance, mostly surface ablation (~46%). На основе разновременных ЦМР установлены скорости изменения высоты поверхности ледникового купола Академии Наук на Северной Земле за два периода: 2004−2016 и 2012/2013−2016 гг. и определён геодезический баланс его массы (−1,72±0,67 Гт/год). Сделан расчёт климатического баланса массы (0,21±0,68 Гт/год) и полной абляции (−3,18 Гт/год) ледника, где на отёл приходится ≈54%, а на поверхностную абляцию – ≈46%. |
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