Estimation of surface upward longwave radiation from MODIS and VIIRS clear-sky data in the Tibetan Plateau

作者:Jiao, ZH (Jiao, Zhonghu)[ 1 ] ; Yan, GJ (Yan, Guangjian)[ 1 ] ; Zhao, J (Zhao, Jing)[ 1 ] ; Wang, TX (Wang, Tianxing)[ 2 ] ; Chen, L (Chen, Ling)[ 3 ]

REMOTE SENSING OF ENVIRONMENT

卷: 162  页: 221-237

DOI: 10.1016/j.rse.2015.02.021

出版年: JUN 1 2015

摘要

Surface upward longwave radiation (SULR) is one critical component of the surface energy balance and is closely related to the surface temperature fields. The SULR with the moderate spatial resolution and appropriate precision in the Tibetan Plateau, a large and complex cryosphere, can enhance our understanding of the land surface processes, atmospheric circulations and even global climate change. The purpose of this paper is to estimate SULR from top-of-atmosphere (TOA) radiances of Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS). A hybrid method is proposed that combines extensive radiative transfer simulation and the Artificial Neuron Network (ANN) statistical model. For the sake of ensuring the availability of the simulation database, the eligible profiles from MODIS atmospheric profiles product were screened according to five criteria. And then the analyses on the important parameters of the simulation dataset were performed to check the integrality of this dataset Moreover, the variables' importance was analyzed, and TOA radiances of MODIS channels 29, 31, 32 and 33 (or VIIRS channels M14, M15 and M16) and sensor view zenith angle (VZA) were selected to retrieve SULR The ANN-based retrieval model was created finally based on this simulation dataset The evaluation showed good agreements for both MODIS and VIIRS training and testing datasets with R-2 greater than 0.98. The MODIS SULR was validated using two-year ground-measured data at seven sites in the Tibetan Plateau with R-2 of 0.886, root-mean-square error (RMSE) of 26.985W m(-2) and mean bias error (MBE) of 10.812W m(-2) as a whole. And the relevance was obvious from the overall trend and distribution though the discrepancy was relatively large when directly comparing SULR from VIIRS and MODIS data. The validation results showed that the ANN model is a good nonlinear model to retrieve SULR with the TOA radiances and VZA. (C) 2015 Elsevier Inc All rights reserved.

通讯作者地址: Yan, GJ (通讯作者)

Beijing Normal Univ, Sch Geog, State Key Lab Remote Sensing Sci, Beijing 100875, Peoples R China.

地址:

[ 1 ] Beijing Normal Univ, Sch Geog, State Key Lab Remote Sensing Sci, Beijing 100875, Peoples R China

[ 2 ] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Beijing 100101, Peoples R China

[ 3 ] Beijing Forestry Univ, Acad Forestry, Beijing 100083, Peoples R China