Vertical land motion due to present-day ice loss from Greenland's and Canada's peripheral glaciers

Greenland's bedrock responds to the ongoing loss of ice mass with an elastic vertical land motion (VLM) that is measured by Greenland's GNSS Network (GNET). The measured VLM also contains other contributions, including the long-term viscoelastic response of the Earth to previous deglaciation. Greenland's ice sheet (GrIS) is producing the most significant contribution to the total VLM. The contribution of peripheral glaciers (PGs) from both Greenland (GrPGs) and Arctic Canada (CanPGs) has not been carefully accounted for in the GNSS time series analysis. This is a significant concern, since GNET stations are often closer to PGs than to the ice sheet. We find that PGs produce significant elastic rebound, especially in North and East Greenland. Across these regions, the PGs result in up to 37% of the elastic rebound. For a few stations in the North, the VLM from PGs is larger than the GrIS one.

格陵兰基岩会因持续的冰量流失产生弹性垂直陆地运动（vertical land motion, VLM），该运动可通过格陵兰GNSS网络（Greenland's GNSS Network, GNET）进行观测。实测得到的VLM还包含其他贡献项，包括地球对以往冰消作用的长期黏弹性响应。格陵兰冰盖（Greenland's ice sheet, GrIS）对总VLM的贡献最为显著。来自格陵兰周边冰川（peripheral glaciers, PGs，其中格陵兰本地周边冰川记为GrPGs、加拿大北极地区周边冰川记为CanPGs）的贡献，在GNSS时间序列分析中尚未得到充分考量。这一点值得高度关注，因为GNET观测站通常距离周边冰川比距离冰盖更近。研究发现，周边冰川会引发显著的弹性回弹，尤其在格陵兰北部与东部区域。在上述区域中，周边冰川贡献的弹性回弹占比最高可达37%。格陵兰北部的部分观测站中，周边冰川引发的VLM甚至超过了格陵兰冰盖的贡献。