Miles Bertie W J, Stokes Chris R, Jamieson Stewart S R, Jordan Jim R, Gudmundsson G Hilmar, Jenkins Adrian
School of Geosciences, Edinburgh University, Edinburgh, EH8 9XP, UK.
Department of Geography, Durham University, Durham, DH1 3LE, UK.
Sci Rep. 2022 Jun 29;12(1):10968. doi: 10.1038/s41598-022-13517-2.
Antarctica's contribution to global mean sea level rise has been driven by an increase in ice discharge into the oceans. The rate of change and the mechanisms that drive variability in ice discharge are therefore important to consider in the context of projected future warming. Here, we report observations of both decadal trends and inter-annual variability in ice discharge across the Antarctic Ice Sheet at a variety of spatial scales that range from large drainage basins to individual outlet glacier catchments. Overall, we find a 37 ± 11 Gt year increase in discharge between 1999 and 2010, but a much smaller increase of 4 ± 8 Gt year between 2010 and 2018. Furthermore, comparisons reveal that neighbouring outlet glaciers can behave synchronously, but others show opposing trends, despite their close proximity. We link this spatial and temporal variability to changes in ice shelf buttressing and the modulating effect of local glacier geometry.
南极洲对全球平均海平面上升的贡献是由其向海洋排放的冰量增加所驱动的。因此，在预测未来变暖的背景下，冰排放的变化率及其驱动变率的机制是需要考虑的重要因素。在此，我们报告了在从大型排水盆地到单个出口冰川集水区等各种空间尺度上，整个南极冰盖冰排放的年代际趋势和年际变率的观测结果。总体而言，我们发现1999年至2010年期间排放量增加了37±11亿吨/年，但2010年至2018年期间仅增加了4±8亿吨/年，增幅要小得多。此外，比较结果显示，相邻的出口冰川可能会同步变化，但也有其他冰川尽管距离很近却呈现相反的趋势。我们将这种时空变率与冰架支撑作用的变化以及当地冰川几何形状的调节作用联系起来。
