Instruction - Modelling Sea-Surface Reflectance factor

The sea-surface reflectance factor, ρ, is used to remove skyglint and sunglint from above-water measurements of water’s reflectance.

To calculate ρ with a solar zenith angle of 30°, viewing zenith angle of 40° and a relative azimuth angle of 135°:

import tmart
rho = tmart.surface_rho.calculate(wl=400, viewing_zenith=40, solar_zenith=30, relative_azimuth=135)
print(rho)

Note that Windows users need to wrap the code within << if __name__ == “__main__” >> because it is required to call functions that use the multiprocessing library in Windows.

To change the default AOT₅₅₀ of 0.05 and wind speed of 3 m/s:

rho = tmart.surface_rho.calculate(wl=400, viewing_zenith=40, solar_zenith=30, relative_azimuth=135, aot550=0.05, wind_speed = 8)
print(rho)

To calculate the values of ρ from 400 to 800 nm at an interval of 100 nm:

rho = tmart.surface_rho.calculate(wl=[400,800,100], viewing_zenith=40, solar_zenith=30, relative_azimuth=135, aot550=0.05, wind_speed = 8)
print(rho)

Other parameters of the function include atmosphere type, aerosol type, number of photons for computation. See full parameters and their descriptions HERE.

Publication

Wu, Y., & Knudby, A. (2023). A Tool That Calculates The Sea-Surface Reflectance Factor In Customized Environments And Geometry. IGARSS 2023 - 2023 IEEE International Geoscience and Remote Sensing Symposium, 464–467. https://doi.org/10.1109/IGARSS52108.2023.10282740