气候变化领域集成服务门户(CCPortal): Estimating ice albedo from fine debris cover quantified by a semi-automatic method: The case study of Forni Glacier, Italian Alps

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DOI	10.5194/tc-10-665-2016
	Estimating ice albedo from fine debris cover quantified by a semi-automatic method: The case study of Forni Glacier, Italian Alps
	Sergio Azzoni R.; Senese A.; Zerboni A.; Maugeri M.; Smiraglia C.; Adele Diolaiuti G.
发表日期	2016
ISSN	19940416
卷号	10 期号:2
英文摘要	In spite of the quite abundant literature focusing on fine debris deposition over glacier accumulation areas, less attention has been paid to the glacier melting surface. Accordingly, we proposed a novel method based on semi-automatic image analysis to estimate ice albedo from fine debris coverage (d). Our procedure was tested on the surface of a wide Alpine valley glacier (the Forni Glacier, Italy), in summer 2011, 2012 and 2013, acquiring parallel data sets of in situ measurements of ice albedo and high-resolution surface images. Analysis of 51 images yielded d values ranging from 0.01 to 0.63 and albedo was found to vary from 0.06 to 0.32. The estimated d values are in a linear relation with the natural logarithm of measured ice albedo (R =-0.84). The robustness of our approach in evaluating d was analyzed through five sensitivity tests, and we found that it is largely replicable. On the Forni Glacier, we also quantified a mean debris coverage rate (Cr) equal to 6gm-2 per day during the ablation season of 2013, thus supporting previous studies that describe ongoing darkening phenomena at Alpine debris-free glaciers surface. In addition to debris coverage, we also considered the impact of water (both from melt and rainfall) as a factor that tunes albedo: meltwater occurs during the central hours of the day, decreasing the albedo due to its lower reflectivity; instead, rainfall causes a subsequent mean daily albedo increase slightly higher than 20 %, although it is short-lasting (from 1 to 4 days). © 2016 Author(s).
学科领域	ablation; albedo; algorithm; fines; ice-rafted debris; image analysis; image resolution; in situ measurement; meltwater; precipitation intensity; valley glacier; Alps; Forni Glacier; Italy; Lombardy; Sondrio
语种	英语
scopus关键词	ablation; albedo; algorithm; fines; ice-rafted debris; image analysis; image resolution; in situ measurement; meltwater; precipitation intensity; valley glacier; Alps; Forni Glacier; Italy; Lombardy; Sondrio
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/119684
作者单位	Università Degli Studi di Milano, Dipartimento di Scienze della Terra A. Desio, Milan, Italy; Università Degli Studi di Milano, Dipartimento di Fisica, Milan, Italy
推荐引用方式 GB/T 7714	Sergio Azzoni R.,Senese A.,Zerboni A.,et al. Estimating ice albedo from fine debris cover quantified by a semi-automatic method: The case study of Forni Glacier, Italian Alps[J],2016,10(2).
APA	Sergio Azzoni R.,Senese A.,Zerboni A.,Maugeri M.,Smiraglia C.,&Adele Diolaiuti G..(2016).Estimating ice albedo from fine debris cover quantified by a semi-automatic method: The case study of Forni Glacier, Italian Alps.Cryosphere,10(2).
MLA	Sergio Azzoni R.,et al."Estimating ice albedo from fine debris cover quantified by a semi-automatic method: The case study of Forni Glacier, Italian Alps".Cryosphere 10.2(2016).