The invention provides a high-precision
satellite MODIS (Moderate-resolution Imaging
Spectroradiometer) monitoring method for
chlorophyll a of a eutrophic
lake water body. The method comprises the following steps: screening a
chlorophyll a evaluation index (NDBI) which is sensitive to the concentration change of the
chlorophyll a and is not influenced by high
suspended solids; obtaining a quantitative relation between the NDBI and the concentration of the
chlorophyll a on the basis of biological optical
model simulation; combining spectral information of the
water body and the corresponding concentration of the
chlorophyll a of the
water body monitored in the field in Chaohu Lake in year 2013-2014, so as to obtain a
chlorophyll a inversion
algorithm based on a ground measured spectrum (Rrs) and the NDBI; simulating different
aerosol types and thicknesses, different solar altitudes,
satellite observation angles and
azimuth angles, so as to obtain a quantitative relation between the ground monitored
remote sensing reflectance (Rrs) and simulated Rrc subjected to
Rayleigh scattering correction; and further extending the chlorophyll a inversion
algorithm based on ground measured
spectral data to
satellite image data subjected to the
Rayleigh scattering correction. According to the method, the inter-annual and inter-monthly change rules and space distribution of the rules of the concentration of the chlorophyll a of a eutrophic lake can be accurately obtained.