Title
Simulation and Analysis of the Topographic Effects on Snow-Free Albedo over Rugged Terrain.
Abstract
Topography complicates the modeling and retrieval of land surface albedo due to shadow effects and the redistribution of incident radiation. Neglecting topographic effects may lead to a significant bias when estimating land surface albedo over a single slope. However, for rugged terrain, a comprehensive and systematic investigation of topographic effects on land surface albedo is currently ongoing. Accurately estimating topographic effects on land surface albedo over a rugged terrain presents a challenge in remote sensing modeling and applications. In this paper, we focused on the development of a simplified estimation method for snow-free albedo over a rugged terrain at a 1-km scale based on a 30-m fine-scale digital elevation model (DEM). The proposed method was compared with the radiosity approach based on simulated and real DEMs. The results of the comparison showed that the proposed method provided adequate computational efficiency and satisfactory accuracy simultaneously. Then, the topographic effects on snow-free albedo were quantitatively investigated and interpreted by considering the mean slope, subpixel aspect distribution, solar zenith angle, and solar azimuth angle. The results showed that the more rugged the terrain and the larger the solar illumination angle, the more intense the topographic effects were on black-sky albedo (BSA). The maximum absolute deviation (MAD) and the maximum relative deviation (MRD) of the BSA over a rugged terrain reached 0.28 and 85%, respectively, when the SZA was 60 degrees for different terrains. Topographic effects varied with the mean slope, subpixel aspect distribution, SZA and SAA, which should not be neglected when modeling albedo.
Year
DOI
Venue
2018
10.3390/rs10020278
REMOTE SENSING
Keywords
Field
DocType
land surface albedo,snow-free albedo,rugged terrain,topographic effects,black-sky albedo (BSA)
Solar azimuth angle,Illumination angle,Topographic map,Terrain,Remote sensing,Albedo,Solar zenith angle,Digital elevation model,Subpixel rendering,Geology
Journal
Volume
Issue
ISSN
10
2
2072-4292
Citations 
PageRank 
References 
3
0.38
15
Authors
8
Name
Order
Citations
PageRank
Dalei Hao164.49
Jianguang Wen26721.30
Qing Xiao35211.09
Shengbiao Wu472.48
Lin Xingwen562.12
Baocheng Dou6366.18
Dongqin You73810.25
yong tang8315.70