We investigate the influence of the curvature of the Earth on a proposed atmospheric-correction scheme for the Sea-Viewing Wide-Field-of-View Sensor (SeaWiFS) by simulating the radiance exiting the top of a spherical-shell atmosphere and inserting the result into the proposed correction algorithm. The error in the derived water-leaving reflectance suggests that the effects of the curvature are negligible for solar zenith angles (θ0) ≤ 70°. Furthermore, for θ0 > 70° the error in atmospheric correction can usually be reduced if the molecular-scattering component of the top of the atmosphere reflectance (ρr) is computed with a spherical-shell atmosphere radiative transfer code. Also, for θ0 > 70° the error in atmospheric correction in a spherical-shell atmosphere, when ρr is computed with a spherical-shell model, can be predicted reasonably well from computations made with plane-parallel atmosphere radiative transfer codes. This implies that studies aimed at improving atmospheric correction can be made assuming plane-parallel geometry and that the investigator can be confident when θ0 > 70° that any improvements will still be valid for a spherical-shell atmosphere as long as ρr is computed in spherical-shell geometry. Finally, a scheme for computing ρr in a spherical-shell atmosphere in a relatively simple manner is developed.
© 1994 Optical Society of America
Original Manuscript: December 22, 1993
Revised Manuscript: April 21, 1994
Published: October 20, 1994
Kuiyuan Ding and Howard R. Gordon, "Atmospheric correction of ocean-color sensors: effects of the Earth’s curvature," Appl. Opt. 33, 7096-7106 (1994)