Greene Chad A, Blankenship Donald D, Gwyther David E, Silvano Alessandro, van Wijk Esmee
Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78758, USA.
Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78712, USA.
Sci Adv. 2017 Nov 1;3(11):e1701681. doi: 10.1126/sciadv.1701681. eCollection 2017 Nov.
Totten Glacier in East Antarctica has the potential to raise global sea level by at least 3.5 m, but its sensitivity to climate change has not been well understood. The glacier is coupled to the ocean by the Totten Ice Shelf, which has exhibited variable speed, thickness, and grounding line position in recent years. To understand the drivers of this interannual variability, we compare ice velocity to oceanic wind stress and find a consistent pattern of ice-shelf acceleration 19 months after upwelling anomalies occur at the continental shelf break nearby. The sensitivity to climate forcing we observe is a response to wind-driven redistribution of oceanic heat and is independent of large-scale warming of the atmosphere or ocean. Our results establish a link between the stability of Totten Glacier and upwelling near the East Antarctic coast, where surface winds are projected to intensify over the next century as a result of increasing atmospheric greenhouse gas concentrations.
东南极洲的托滕冰川有可能使全球海平面至少上升3.5米,但其对气候变化的敏感性尚未得到充分了解。该冰川通过托滕冰架与海洋相连,近年来托滕冰架的速度、厚度和接地线位置都呈现出变化。为了了解这种年际变化的驱动因素,我们将冰速与海洋风应力进行比较,发现在附近大陆架断裂处出现上升流异常19个月后,冰架加速存在一致的模式。我们观察到的对气候强迫的敏感性是对风驱动的海洋热量重新分布的一种响应,并且与大气或海洋的大规模变暖无关。我们的研究结果建立了托滕冰川稳定性与东南极海岸附近上升流之间的联系,由于大气温室气体浓度增加,预计下个世纪该地区的地表风将增强。