Greenland ice sheet climate disequilibrium and committed sea-level rise
Greenland ice sheet climate disequilibrium and committed sea-level rise
复制标题
DOI：
10.1038/s41558-022-01441-2
复制
发表时间：
2022-08-29
影响因子：
30.7
通讯作者：
Fausto，Robert S.
中科院分区：
文献类型：
--
作者：
Box，Jason E.;Hubbard，Alun;Fausto，Robert S.
格陵兰冰盖的冰流失是当代海平面上升（SLR）的最大来源之一。虽然基于过程的模型对格陵兰岛冰川消融设定了时间尺度，但模型的缺陷（包括不精确的大气和海洋耦合）掩盖了它们的信心。在这里，我们提出了一种补充方法，解决冰盖与卫星衍生的裸冰范围、潮水区冰流排放和表面质量平衡数据限制的气候不平衡问题。我们发现，无论二十一世纪的气候路径如何，格陵兰冰与近期（2000-2019）气候的不平衡导致59±15×103km2冰退缩至少274±68mm SLR，相当于3.3±0.9%的体积损失。这是由于降水、冰流排放和融水径流导致质量周转增加的结果。永久适用的 2012 年高融化年份导致冰损失承诺为 782±135mm SLR，这对格陵兰岛在 21 世纪变暖过程中的轨迹是一个不祥的预测。
Ice loss from the Greenland ice sheet is one of the largest sources of contemporary sea-level rise (SLR). While process-based models place timescales on Greenland’s deglaciation, their confidence is obscured by model shortcomings including imprecise atmospheric and oceanic couplings. Here, we present a complementary approach resolving ice sheet disequilibrium with climate constrained by satellite-derived bare-ice extent, tidewater sector ice flow discharge and surface mass balance data. We find that Greenland ice imbalance with the recent (2000–2019) climate commits at least 274 ± 68 mm SLR from 59 ± 15 × 103km2ice retreat, equivalent to 3.3 ± 0.9% volume loss, regardless of twenty-first-century climate pathways. This is a result of increasing mass turnover from precipitation, ice flow discharge and meltwater run-off. The high-melt year of 2012 applied in perpetuity yields an ice loss commitment of 782 ± 135 mm SLR, serving as an ominous prognosis for Greenland’s trajectory through a twenty-first century of warming.