地震波探査によるカービング氷河高速流動メカニズムの解明

最近冰川的急剧退缩和大量损失是气候变化最明显的后果之一。在冰川动力学中，最不为人所知的因素是难以接近的冰川/基底过程，以及最终导致大冰山崩塌和冰川进一步退缩的冰裂演化，这些因素与快速流动的入海冰川的质量损失有关。其中一些过程产生的声波通过冰/岩石和空气传播，可以被监测并用于理解否则无法到达的快速现象。这些现场记录是在2015年对格陵兰岛鲍登冰川进行的一次全面国际考察中获得的。最近发表的分析揭示了潮汐调制地震活动的机制（作为冰破裂临时模式的代表）[Podolskiy等人，GRL, 2016]。我们还注意到，为了适应该研究员的新情况，以及2015年12月开始担任助理教授的新工作而提前终止奖学金的可能性，最初提议的冰川的地理位置必须从巴塔哥尼亚改为格陵兰岛。否则就不可能在奖学金提前结束之前进行夏季野外工作（南半球的夏季活动应该在2016年1 - 2月进行，而格陵兰岛的夏季活动可能在2015年7 - 8月举行）。尽管发生了这种变化，但研究的目标基本保持不变，并像最初提出的那样，将重点放在地震观测上，以了解冰川动力学。

Recent dramatic retreat and mass-loss of glaciers is one of the most evident consequences of the climate change. Among the least understood elements of glacier dynamics, related to mass-loss of fast flowing ocean-terminating glaciers, are difficult-to-access englacial / basal processes, and evolution of ice fractures ultimately leading to major iceberg collapse and thus to further retreat of glaciers. Sound waves produced by some of these processes and propagating through ice/rock and air can be monitored and used to understand otherwise unreachable rapid phenomena. Such in situ records were obtained during a comprehensive international expedition to the Bowdoin Glacier, Greenland in 2015. Analysis revealed the mechanisms of tide-modulated seismicity (as a proxy for ice fracturing temporary patterns) and were recently published [Podolskiy et al., GRL, 2016]. We also note, that in order to accommodate new circumstances of the fellow and a possibility of an early termination of the fellowship for starting a new job as an Assistant Professor in Dec 2015, the geographical location of the initially proposed glacier had to be changed from Patagonia to Greenland. Otherwise it would be impossible to conduct summer field work before the early end of the fellowship (summer campaign in southern hemisphere was supposed to take place in Jan-Feb 2016; while for Greenland it was possible to held in Jul-Aug 2015). Despite this change, objectives of the study remained principally intact and were focused on seismic observations for understanding glacier dynamics, as initially proposed.