气候变化领域集成服务门户(CCPortal): Quantifying spatiotemporal variability of glacier algal blooms and the impact on surface albedo in southwestern Greenland

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DOI	10.5194/tc-14-2687-2020
	Quantifying spatiotemporal variability of glacier algal blooms and the impact on surface albedo in southwestern Greenland
	Wang S.; Tedesco M.; Alexander P.; Xu M.; Fettweis X.
发表日期	2020
ISSN	19940416
起始页码	2687
结束页码	2713
卷号	14 期号:8
英文摘要	Albedo reduction due to light-absorbing impurities can substantially enhance ice sheet surface melt by increasing surface absorption of solar energy. Glacier algae have been suggested to play a critical role in darkening the ablation zone in southwestern Greenland. It was very recently found that the Sentinel-3 Ocean and Land Colour Instrument (OLCI) band ratio R709 nm=R673 nm can characterize the spatial patterns of glacier algal blooms. However, Sentinel-3 was launched in 2016, and current data are only available over three melting seasons (2016 2019). Here, we demonstrate the capability of the MEdium Resolution Imaging Spectrometer (MERIS) for mapping glacier algae from space and extend the quantification of glacier algal blooms over southwestern Greenland back to the period 2004 2011. Several band ratio indices (MERIS chlorophyll a indices and the impurity index) were computed and compared with each other. The results indicate that the MERIS two-band ratio index (2BDA) R709 nm=R665 nm is very effective in capturing the spatial distribution and temporal dynamics of glacier algal growth on bare ice in July and August. We analyzed the interannual (2004 2011) and summer (July August) trends of algal distribution and found significant seasonal and interannual increases in glacier algae close to the Jakobshavn Isbrae Glacier and along the middle dark zone between the altitudes of 1200 and 1400 m. Using broadband albedo data from the Moderate Resolution Imaging Spectroradiometer (MODIS), we quantified the impact of glacier algal growth on bare ice albedo, finding a significant correlation between algal development and albedo reduction over algae-abundant areas. Our analysis indicates the strong potential for the satellite algal index to be used to reduce bare ice albedo biases in regional climate model simulations. © 2020 Copernicus GmbH. All rights reserved.
英文关键词	albedo; algal bloom; chlorophyll a; climate modeling; ice sheet; MERIS; MODIS; simulation; solar power; spatiotemporal analysis; Arctic; Greenland; Jakobshavn Glacier; algae
语种	英语
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/202241
作者单位	Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, United States; Department of Geography, Earth and Environmental Systems Institute (EESI), And Institute for Computational and Data Sciences, Pennsylvania State University, University Park, PA 16802, United States; NASA Goddard Institute for Space Studies, New York, NY 10025, United States; College of Marine Science, University of South Florida, St. Petersburg, FL 33701, United States; Department of Geography, SPHERES Research Unit, University of Liège, Liège, 4000, Belgium
推荐引用方式 GB/T 7714	Wang S.,Tedesco M.,Alexander P.,et al. Quantifying spatiotemporal variability of glacier algal blooms and the impact on surface albedo in southwestern Greenland[J],2020,14(8).
APA	Wang S.,Tedesco M.,Alexander P.,Xu M.,&Fettweis X..(2020).Quantifying spatiotemporal variability of glacier algal blooms and the impact on surface albedo in southwestern Greenland.Cryosphere,14(8).
MLA	Wang S.,et al."Quantifying spatiotemporal variability of glacier algal blooms and the impact on surface albedo in southwestern Greenland".Cryosphere 14.8(2020).