Ocean impacts on tidewater glaciers in the Canadian Arctic

海洋对加拿大北极潮水冰川的影响

• 批准号: RTI-2018-00560
• 负责人: Copland, Luke
• 金额: $ 7.06万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=642273
• 关键词: Ocean; impacts; tidewater; glaciers; Canadian

We are requesting funds for oceanographic field equipment to investigate the role of ocean water in controlling the basal melt rates and stability of glaciers in the Canadian Arctic Archipelago (CAA). Glacier mass loss from this region has been the largest contributor to global eustatic sea level rise outside of Greenland and Antarctica over the past 10-15 years, but we currently have a poor understanding of the importance of atmospheric vs. glaciological vs. oceanographic factors in controlling these mass losses. Notably, of the several hundred marine-terminating glaciers in the CAA, just two, Trinity and Wykeham, currently account for ~62% of total iceberg discharge to the ocean. Since the year 2000 these glaciers have more than doubled in speed and their termini have retreated by up to 5 km, meaning that a significant concern is whether irreversible collapse of these ice masses has already begun. The cause of this anomalous retreat is unknown, but preliminary evidence suggests that warm subsurface Atlantic Water, which has been linked to widespread glacier retreat in Greenland, may have propagated into Talbot Inlet, the fjord in front of the glaciers. Further propagation of Atlantic Water into the CAA could cause more widespread glacier acceleration and retreat throughout this region, with broad implications for sea level rise and the export of freshwater (both liquid and solid) into Baffin Bay.

我们正在为海洋实地设备申请资金，以调查海水在控制加拿大北极群岛(CAA)冰川基本融化速度和稳定性方面的作用。该地区的冰川质量损失是过去10-15年格陵兰和南极洲以外全球海平面上升的最大贡献者，但目前我们对大气、冰川和海洋因素在控制这些质量损失中的重要性认识不足。值得注意的是，在CAA的数百个终止海洋的冰川中，只有两个冰川--三一冰川和威克汉姆冰川--目前占到冰山向海洋排放总量的62%。自2000年以来，这些冰川的速度增加了一倍多，冰川末端后退了5公里，这意味着一个重要的问题是，这些冰块是否已经开始不可逆转的崩溃。这种异常退缩的原因尚不清楚，但初步证据表明，与格陵兰大范围冰川退缩有关的温暖的次表层大西洋水可能已经传播到冰川前面的峡湾塔尔博特湾。大西洋水进一步进入CAA可能在整个区域造成更大范围的冰川加速和消退，对海平面上升和淡水(液体和固体)出口到巴芬湾具有广泛的影响。