Publications

Chen, Jun; Zhao, Qisheng (2014). An approach for estimating MODIS reflectance at top-of-atmosphere at 667 and 678 nm from reflectance at 645 nm in turbid waters. ENVIRONMENTAL EARTH SCIENCES, 71(3), 1105-1114.

Abstract
Owing to the defaults of MODIS sensor at 667 and 678 nm, data loss may occur when water bodies are highly turbid. A model for estimating MODIS signals at 667 and 678 nm from the signals at 645 nm (MMSS) is developed and constructed here to estimate the MODIS reflectance at top-of-atmosphere at 667 and 678 nm from the reflectance at 645 nm in highly turbid waters. The model is calibrated and validated by a dataset which consists of a bio-optical dataset and six MODIS images collected from the Yellow River Estuary, Changjiang River Estuary, and Taihu Lake, China. It is discovered that the linear relationships between signals above water surface are still available at top-of-atmosphere in a small region, even if atmospheric absorption and scattering are present in the process of photon transmission. The MODIS band at 645 nm is the optimal band for constructing the MMSS model. It may be rational that reflectance at 667 and 678 nm at top-of-atmosphere cannot be recorded by MODIS sensors while the values are larger than 0.76. The MMSS model produces strong performances in retrieving reflectance at top-of-atmosphere at 667 and 678 nm from the reflectance at 645 nm in turbid waters, with an uncertainty of less than 1.21 %. By comparison with the uncertainty of 2-3 % associated with "noise equivalent reflectance", the uncertainty in the MMSS algorithm predictions (< 1.21 %) is not significant.

DOI:
10.1007/s12665-013-2514-9

ISSN:
1866-6280; 1866-6299