DocumentCode :
15058
Title :
Mapping High-Resolution Surface Shortwave Net Radiation From Landsat Data
Author :
Dongdong Wang ; Shunlin Liang ; Tao He
Author_Institution :
Dept. of Geogr. Sci., Univ. of Maryland, College Park, MD, USA
Volume :
11
Issue :
2
fYear :
2014
fDate :
Feb. 2014
Firstpage :
459
Lastpage :
463
Abstract :
Maps of high-resolution surface shortwave net radiation (SSNR) are important for resolving differences in the surface energy budget at the ecosystem level. The maps can also bridge the gap between existing coarse-resolution SSNR products and point-based field measurements. This study presents a modified hybrid method to estimate both instantaneous and daily SSNR from Landsat data. SSNR values are directly linked to Landsat top-of-atmosphere reflectance by extensive radiative transfer simulation. Regression coefficients are pre-calculated and stored in a look-up table (LUT). Atmospheric water vapor is a key parameter affecting SSNR, and three methods of treating water vapor are evaluated in this study. Comparison between Landsat retrievals and field measurements at six AmeriFlux sites shows that the hybrid method with water vapor as a dimension of LUT can estimate SSNR with a root mean square error of 77.5 W/m2 (instantaneous) and 36.1 W/m2 (daily). The method of water vapor correction produces similar results. However, a generic LUT that covers all levels of water vapor results in much larger errors.
Keywords :
atmospheric humidity; atmospheric radiation; remote sensing; AmeriFlux sites; Landsat data; atmospheric water vapor; coarse resolution SSNR products; ecosystem level; high resolution SSNR; high resolution surface shortwave net radiation mapping; lookup table; point based field measurements; radiative transfer simulation; regression coefficients; surface energy budget; top-of-atmosphere reflectance; Albedo; Enhanced Thematic Mapper Plus (ETM+); Landsat; daily radiation; hybrid method; net radiation; water vapor correction;
fLanguage :
English
Journal_Title :
Geoscience and Remote Sensing Letters, IEEE
Publisher :
ieee
ISSN :
1545-598X
Type :
jour
DOI :
10.1109/LGRS.2013.2266317
Filename :
6549109
Link To Document :
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