Diverging future surface mass balance between the Antarctic ice shelves and grounded ice sheet
نویسندگان
چکیده
Abstract. The future surface mass balance (SMB) will influence the ice dynamics and contribution of Antarctic sheet (AIS) to sea level rise. Most recent SMB projections were based on fifth phase Coupled Model Intercomparison Project (CMIP5). However, new CMIP6 results have revealed a +1.3 ?C higher mean near-surface temperature than in CMIP5 at end 21st century, enabling estimations warmer climates. Here, we investigate AIS sensitivity different warmings with an ensemble four simulations performed polar regional climate model Modèle Atmosphérique Régional (MAR) forced by two models over 1981–2100. Statistical extrapolation enables us expand our whole ensembles. Our highlight contrasting effect grounded shelves. is projected increase as response stronger snowfall, only partly offset enhanced meltwater run-off. This leads cumulated sea-level-rise mitigation (i.e. mass) 5.1 ± 1.9 cm equivalent (SLE) CMIP5-RCP8.5 (Relative Concentration Pathway 8.5) 6.3 2.0 SLE CMIP6-ssp585 (Shared Socioeconomic Pathways 585). Additionally, low-emission ssp126 intermediate-emission ssp245 scenarios project stabilized gain, resulting lower rise ssp585. Over shelves, strong run-off associated decrease (more strongly compared CMIP5-RCP8.5). Ice shelves are however predicted close-to-present-equilibrium stable under scenarios. Future uncertainties mainly due anthropogenic forcing timing warming. While should remain close-to-equilibrium Paris Agreement, MAR projects for warming above +2.5 1981–2010 temperature, limiting range before potential irreversible damages Finally, reveal existence threshold (+7.5 ?C) that grounded-SMB increase. has be confirmed following studies using more extreme or longer
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ژورنال
عنوان ژورنال: The Cryosphere
سال: 2021
ISSN: ['1994-0424', '1994-0416']
DOI: https://doi.org/10.5194/tc-15-1215-2021