Simulated last deglaciation of the Barents Sea Ice Sheet primarily driven by oceanic conditions

QUATERNARY SCIENCE REVIEWS

卷:238

Article

Petrini, Michele^1,11  Colleoni, Florence¹  Kirchner, Nina^2,3  Hughes, Anna L. C.^4,5,6  Camerlenghi, Angelo¹  Rebesco, Michele¹  Lucchi, Renata G.^1,7  Forte, Emanuele⁸  Colucci, Renato R.⁹  Noormets, Riko¹⁰  Mangerud, Jan^4,5 

[1] OGS Ist Nazl Oceanog & Geofis Sperimentale, Borgo Grotta Gigante 42-c, I-34010 Sgonico, TS, Italy

[2] Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden

[3] Stockholm Univ, Dept Phys Geog, SE-10691 Stockholm, Sweden

[4] Univ Bergen, Dept Earth Sci, N-5007 Bergen, Norway

[5] Bjerknes Ctr Climate Res, N-5007 Bergen, Norway

[6] Univ Manchester, Dept Geog, Oxford Rd, Manchester M13 9PL, Lancs, England

[7] Arctic Univ Norway, Ctr Arctic Gas Hydrate Cage, Environm & Climate UiT, Tromso, Norway

[8] Univ Trieste, Dipartimento Matemat & Geosci, Via Weiss 1, I-34128 Trieste, TS, Italy

[9] ISMAR Ist Sci Marine, Trieste, Italy

[10] Univ Ctr Svalbard UNIS, POB 156 Northern, N-9171 Longyearbyen, Norway

[11] Delft Univ Technol TUDelft, Dept Geosci & Remote Sensing, Delft, Netherlands

关键词: Quaternary;    Glaciology;    Barents sea;    Ice sheet modelling;    Ocean melting;   

DOI  :  10.1016/j.quascirev.2020.106314

来源: Elsevier

【 摘 要 】

The Barents Sea Ice Sheet was part of an interconnected complex of ice sheets, collectively referred to as the Eurasian Ice Sheet, which covered north-westernmost Europe, Russia and the Barents Sea during the Last Glacial Maximum (around 21 ky BP). Due to common geological features, the Barents Sea component of this ice complex is seen as a paleo-analogue for the present-day West Antarctic Ice Sheet. Investigating key processes driving the last deglaciation of the Barents Sea Ice Sheet represents an important tool to interpret recent observations in Antarctica over the multi-millennial temporal scale of glaciological changes. We present results from a perturbed physics ensemble of ice sheet model simulations of the last deglaciation of the Barents Sea Ice Sheet, forced with transient atmospheric and oceanic conditions derived from AOGCM simulations. The ensemble of transient simulations is evaluated against the databased DATED-1 reconstruction to construct minimum, maximum and average deglaciation scenarios. Despite a large model/data mismatch at the western and eastern ice sheet margins, the simulated and DATED-1 deglaciation scenarios agree well on the timing of the deglaciation of the central and northern Barents Sea. We find that the simulated deglaciation of the Barents Sea Ice Sheet is primarily driven by the oceanic forcing, with prescribed eustatic sea level rise amplifying the ice sheet sensitivity to sub-shelf melting over relatively short intervals. Our results highlight that the sub-shelf melting has a very strong control on the simulated grounding-line flux, showing that a slow, gradual ocean warming trend is capable of triggering sustained grounded ice discharge over multi-millennial timescales, even without taking into account marine ice sheet or ice cliff instability. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

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