气候变化领域集成服务门户(CCPortal): Seasonal mass variations show timing and magnitude of meltwater storage in the Greenland Ice Sheet

CCPortal

DOI	10.5194/tc-12-2981-2018
	Seasonal mass variations show timing and magnitude of meltwater storage in the Greenland Ice Sheet
	Ran J.; Vizcaino M.; Ditmar P.; Van Den Broeke M.R.; Moon T.; Steger C.R.; Enderlin E.M.; Wouters B.; Noël B.; Reijmer C.H.; Klees R.; Zhong M.; Liu L.; Fettweis X.
发表日期	2018
ISSN	19940416
卷号	12 期号:9
英文摘要	The Greenland Ice Sheet (GrIS) is currently losing ice mass. In order to accurately predict future sea level rise, the mechanisms driving the observed mass loss must be better understood. Here, we combine data from the satellite gravimetry mission Gravity Recovery and Climate Experiment (GRACE), surface mass balance (SMB) output of the Regional Atmospheric Climate Model v. 2 (RACMO2), and ice discharge estimates to analyze the mass budget of Greenland at various temporal and spatial scales. We find that the mean rate of mass variations in Greenland observed by GRACE was between ĝ'277 and ĝ'269 Gt yrĝ'1 in 2003-2012. This estimate is consistent with the sum (i.e., ĝ'304±126 Gt yrĝ'1) of individual contributions - surface mass balance (SMB, 216±122 Gt yrĝ'1) and ice discharge (520±31 Gt yrĝ'1) - and with previous studies. We further identify a seasonal mass anomaly throughout the GRACE record that peaks in July at 80-120 Gt and which we interpret to be due to a combination of englacial and subglacial water storage generated by summer surface melting. The robustness of this estimate is demonstrated by using both different GRACE-based solutions and different meltwater runoff estimates (namely, RACMO2.3, SNOWPACK, and MAR3.9). Meltwater storage in the ice sheet occurs primarily due to storage in the high-accumulation regions of the southeast and northwest parts of Greenland. Analysis of seasonal variations in outlet glacier discharge shows that the contribution of ice discharge to the observed signal is minor (at the level of only a few gigatonnes) and does not explain the seasonal differences between the total mass and SMB signals. With the improved quantification of meltwater storage at the seasonal scale, we highlight its importance for understanding glacio-hydrological processes and their contributions to the ice sheet mass variability. © Author(s) 2018.
学科领域	climate modeling; discharge; GRACE; mass balance; meltwater; runoff; seasonal variation; water storage; Arctic; Greenland; Greenland Ice Sheet
语种	英语
scopus关键词	climate modeling; discharge; GRACE; mass balance; meltwater; runoff; seasonal variation; water storage; Arctic; Greenland; Greenland Ice Sheet
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119066
作者单位	Department of Geoscience and Remote Sensing, Delft University of Technology, Delft, Netherlands; Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands; National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, United States; Climate Change Institute, School of Earth and Climate Science, University of Maine, Orono, ME, United States; State Key Laboratory of Geodesy and Earth's Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan, China; Earth System Science Programme, Faculty of Science, Chinese University of Hong Kong, Hong Kong; Department of Geography, University of Liège, Liège, Belgium
推荐引用方式 GB/T 7714	Ran J.,Vizcaino M.,Ditmar P.,et al. Seasonal mass variations show timing and magnitude of meltwater storage in the Greenland Ice Sheet[J],2018,12(9).
APA	Ran J..,Vizcaino M..,Ditmar P..,Van Den Broeke M.R..,Moon T..,...&Fettweis X..(2018).Seasonal mass variations show timing and magnitude of meltwater storage in the Greenland Ice Sheet.Cryosphere,12(9).
MLA	Ran J.,et al."Seasonal mass variations show timing and magnitude of meltwater storage in the Greenland Ice Sheet".Cryosphere 12.9(2018).