期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2010
卷号：XXXVIII - Part 8
页码：1028-1032
出版社：Copernicus Publications
摘要：The study discusses a new supplementary method of masking cloud-affected pixels in satellite ocean color imageries. Pixels, typically found around cloud edge, sometimes have anomalous features either in chlorophyll a concentration or in-water reflectance estimates caused by residual error of inter-band registration correction, or more generally, by differences in the band-wise field-of- view of the detectors. Our method is to check the pixel-wise consistency over the spectral water reflectance R W retrieved by the atmospheric correction. We define two spectral ratio between water reflectance, IRR1 and IRR2, each defined as R W (B1)/R W (B3) and as R W (B2)/R W (B4) respectively, where B1~B4 stand for 4 consecutive visible bands. We show that almost linear relation holds over log-scaled IRR1 and IRR2 for ship-measured R W data of SeaBAM in situ data set. Similar relation with a little more variability is also shown for SeaWiFS and GLI Level 2 sub-scenes. We then introduce a new cloud screening criterion that identifies those pixels that have significant discrepancy from the relationship. We apply this method to ADEOS-II/GLI ocean color data to evaluate the performance over Level-2 data, showing that it saves significant portion of near-cloud pixels yet giving chlorophyll a concentration averages in the near-cloud area that is very close to the ones in "far-cloud" pixels, or pixels that are 5 or more pixels far from the cloud edge. The method will be applicable to other satellite ocean color sensors
