气候变化领域集成服务门户(CCPortal): The surface albedo of the Greenland Ice Sheet between 1982 and 2015 from the CLARA-A2 dataset and its relationship to the ice sheet's surface mass balance

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DOI	10.5194/tc-13-2597-2019
	The surface albedo of the Greenland Ice Sheet between 1982 and 2015 from the CLARA-A2 dataset and its relationship to the ice sheet's surface mass balance
	Riihelä A.; King M.D.; Anttila K.
发表日期	2019
ISSN	19940416
起始页码	2597
结束页码	2614
卷号	13 期号:10
英文摘要	The Greenland Ice Sheet is losing mass at a significant rate, driven in part by increasing surface-melt-induced runoff. Because the ice sheet's surface melt is closely connected to changes in the surface albedo, studying multidecadal changes in the ice sheet's albedo offers insight into surface melt and associated changes in its surface mass balance. Here, we first analyse the CM SAF Cloud, Albedo and Surface Radiation dataset from AVHRR data second edition (CLARA-A2) Surface Albedo (SAL), covering 1982-2015, to obtain decadal albedo trends for each summer month. We also examine the rates of albedo change during the early summer, supported with atmospheric reanalysis data from MERRA-2 (Modern-Era Retrospective analysis for Research and Applications, version 2), to discern changes in the intensity of early summer melt, and their likely drivers. We find that rates of albedo decrease during summer melt have accelerated during the 2000s relative to the early 1980s and that the surface albedos now often decrease to values typical of bare ice at elevations 50-100 m higher on the ice sheet. The southern margins exhibit the opposite behaviour, though, and we suggest this is due to increasing snowfall over the area. We then subtract ice discharge from the mass balance estimates observed by the Gravity Recovery and Climate Experiment (GRACE) satellite mission to estimate surface mass balance. The CLARA-A2 albedo changes are regressed with these data to obtain a summer-aggregated proxy surface mass balance time series for the summer periods 1982-2015. This proxy time series is compared with latest regional climate model estimates from the MAR model to perform an observation-based test on the dominance of surface runoff in the magnitude and variability of the summer surface mass balance. We show that the proxy time series agrees with MAR through the analysed period within the associated uncertainties of the data and methods, demonstrating and confirming that surface runoff has dominated the rapid surface mass loss period between the 1990s and 2010s. Finally, we extend the analysis to the drainage basin scale to examine discharge-albedo relationships. We find little evidence of surface-melt-induced ice flow acceleration at annual timescales. © 2019 Author(s). This work is distributed under the Creative Commons Attribution 4.0 License.
语种	英语
scopus关键词	AVHRR; climate modeling; data set; drainage basin; GRACE; ice sheet; regional climate; runoff; satellite mission; time series; uncertainty analysis; Arctic; 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/125169
作者单位	Finnish Meteorological Institute, Meteorological Research, Helsinki, 00560, Finland; Byrd Polar and Climate Research Center, Columbus, United States; School of Earth Sciences, Ohio State University, Columbus, United States
推荐引用方式 GB/T 7714	Riihelä A.,King M.D.,Anttila K.. The surface albedo of the Greenland Ice Sheet between 1982 and 2015 from the CLARA-A2 dataset and its relationship to the ice sheet's surface mass balance[J],2019,13(10).
APA	Riihelä A.,King M.D.,&Anttila K..(2019).The surface albedo of the Greenland Ice Sheet between 1982 and 2015 from the CLARA-A2 dataset and its relationship to the ice sheet's surface mass balance.The Cryosphere,13(10).
MLA	Riihelä A.,et al."The surface albedo of the Greenland Ice Sheet between 1982 and 2015 from the CLARA-A2 dataset and its relationship to the ice sheet's surface mass balance".The Cryosphere 13.10(2019).