气候变化领域集成服务门户(CCPortal): Modeling the response of northwest Greenland to enhanced ocean thermal forcing and subglacial discharge

CCPortal

DOI	10.5194/tc-13-723-2019
	Modeling the response of northwest Greenland to enhanced ocean thermal forcing and subglacial discharge
	Morlighem M.; Wood M.; Seroussi H.; Choi Y.; Rignot E.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	723
结束页码	734
卷号	13 期号:2
英文摘要	Calving-front dynamics is an important control on Greenland's ice mass balance. Ice front retreat of marine-terminating glaciers may, for example, lead to a loss in resistive stress, which ultimately results in glacier acceleration and thinning. Over the past decade, it has been suggested that such retreats may be triggered by warm and salty Atlantic Water, which is typically found at a depth below 200-300m. An increase in subglacial water discharge at glacier ice fronts due to enhanced surface runoff may also be responsible for an intensification of undercutting and calving. An increase in ocean thermal forcing or subglacial discharge therefore has the potential to destabilize marine-terminating glaciers along the coast of Greenland. It remains unclear which glaciers are currently stable but may retreat in the future and how far inland and how fast they will retreat. Here, we quantify the sensitivity and vulnerability of marine-terminating glaciers along the northwest coast of Greenland (from 72.5 to 76ĝN) to ocean forcing and subglacial discharge using the Ice Sheet System Model (ISSM). We rely on a parameterization of undercutting based on ocean thermal forcing and subglacial discharge and use ocean temperature and salinity from high-resolution ECCO2 (Estimating the Circulation and Climate of the Ocean, Phase II) simulations at the fjord mouth to constrain the ocean thermal forcing. The ice flow model includes a calving law based on a tensile von Mises criterion. We find that some glaciers, such as Dietrichson Gletscher or Alison Glacier, are sensitive to small increases in ocean thermal forcing, while others, such as Illullip Sermia or Cornell Gletscher, are remarkably stable, even in a +3ĝC ocean warming scenario. Under the most intense experiment, we find that Hayes Gletscher retreats by more than 50km inland by 2100 into a deep trough, and its velocity increases by a factor of 3 over only 23 years. The model confirms that ice-ocean interactions can trigger extensive and rapid glacier retreat, but the bed controls the rate and magnitude of the retreat. Under current oceanic and atmospheric conditions, we find that this sector of the Greenland ice sheet alone will contribute more than 1cm to sea level rise and up to 3cm by 2100 under the most extreme scenario. © Author(s) 2019.
学科领域	atmospheric forcing; discharge; fjord; glacier mass balance; hydrological modeling; ice retreat; ice-ocean interaction; iceberg calving; parameterization; runoff; sensitivity analysis; simulation; subglacial environment; vulnerability; water temperature; Arctic; Atlantic Ocean; Greenland; Greenland Ice Sheet
语种	英语
scopus关键词	atmospheric forcing; discharge; fjord; glacier mass balance; hydrological modeling; ice retreat; ice-ocean interaction; iceberg calving; parameterization; runoff; sensitivity analysis; simulation; subglacial environment; vulnerability; water temperature; Arctic; Atlantic Ocean; Greenland; Greenland Ice Sheet
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118918
作者单位	Department of Earth System Science, University of California, Irvine, 3218 Croul Hall, Irvine, CA 92697-3100, United States; Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, United States
推荐引用方式 GB/T 7714	Morlighem M.,Wood M.,Seroussi H.,et al. Modeling the response of northwest Greenland to enhanced ocean thermal forcing and subglacial discharge[J],2019,13(2).
APA	Morlighem M.,Wood M.,Seroussi H.,Choi Y.,&Rignot E..(2019).Modeling the response of northwest Greenland to enhanced ocean thermal forcing and subglacial discharge.The Cryosphere,13(2).
MLA	Morlighem M.,et al."Modeling the response of northwest Greenland to enhanced ocean thermal forcing and subglacial discharge".The Cryosphere 13.2(2019).