Characterizing the Pixel Footprint of Satellite AlbedoProducts Derived from MODIS Reflectance in theHeihe River Basin, China

Remote Sensing

Lizhao Wang¹  Qiang Liu¹  Meng Lu²  Wenjie Fan³  Jingjing Peng⁴  Qinhuo Liu⁴  Jianguang Wen⁴ 

[1] College of Global Change and Earth System Science, Beijing Normal University,No. 19 Xinjiekou Road, Haidian District, Beijing 100875, China;Institute for Geoinformatics, Heisenbergstraße 2, D-48149 Münster, Germany;Institute of Remote Sensing and GIS, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, China;State Key Laboratory of Remote Sensing Science, Institute of Remote sensing and Digital Earth, Chinese Academy of Sciences, No. 20 Datun Road, Chaoyang District, Beijing 100101, China;

关键词: geophysical signal processing;    MODIS;    albedo;    spatial response;    point spread function (PSF);   

DOI  :  10.3390/rs70606886

来源: DOAJ

【 摘 要 】

The adjacency effect and non-uniform responses complicate the precise delimitation of the surface support of remote sensing data and their derived products. Thus, modeling spatial response characteristics (SRCs) prior to using remote sensing information has become important. A point spread function (PSF) is typically used to describe the SRCs of the observation cells from remote sensors and is always estimated in a laboratory before the sensor is launched. However, research on the SRCs of high-order remote sensing products derived from the observations remains insufficient, which is an obstacle to converting between multi-scale remote sensing products and validating coarse-resolution products. This study proposed a method that combines simulation and validation to establish SRC models of coarse-resolution albedo products. Two series of commonly used 500-m/1-km resolution albedo products, which are derived from Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data, were investigated using 30-m albedo products that provide the required sub-pixel information. The analysis proves that the size of the surface support of each albedo pixel is larger than the nominal resolution of the pixel and that the response weight is non-uniformly distributed, with an elliptical Gaussian shape. The proposed methodology is generic and applicable for analyzing the SRCs of other advanced remote sensing products.

【 授权许可】

Unknown