An approach to retrieve BRDF from satellite and airborne measurements of surface-reflected radiance based on decoupling of atmospheric radiative transfer and surface reflection

Alexander Radkevich

doi:10.1117/12.2530662

9 October 2019 An approach to retrieve BRDF from satellite and airborne measurements of surface-reflected radiance based on decoupling of atmospheric radiative transfer and surface reflection

Alexander Radkevich

Author Affiliations +

Proceedings Volume 11152, Remote Sensing of Clouds and the Atmosphere XXIV; 111520D (2019) https://doi.org/10.1117/12.2530662
Event: SPIE Remote Sensing, 2019, Strasbourg, France

Abstract

Bi-directional Reflection Distribution Function (BRDF) defines anisotropy of the surface reflection. It is required to specify the boundary condition for radiative transfer (RT) modeling. Measurements of reflected radiance by satellite- and air-borne sensors provide information about anisotropy of surface reflection. Atmospheric correction needs to be performed to derive BRDF from the reflected radiance. Common approach for BRDF retrievals consists of the use of kernel-based BRDF and RT modeling that needs to be done anew at every step of the iterative process. The kernels’ weights are obtained by minimization of the difference between measured and modeled radiance. This study develops a new method of retrieving kernel-based BRDF that requires RT calculations to be done only once. The method employs the exact analytical expression of radiance at any atmospheric level through the solutions to two auxiliary atmosphere-only RT problems and the surface-reflected radiance at the surface level. The latter is related to BRDF and solutions to the auxiliary RT problems by a Fredholm integral equation of the second kind. The approach requires to perform RT calculations one time before the iterations. It can use observations taken at different atmospheric conditions assuming that surface conditions remain unchanged during the time span of observations. The algorithm accurately catches zero weights of the kernels that may be a concern if the number of kernels is greater than 3 in current mainstream approaches. The study presents numerical tests of the BRDF retrieval algorithm for various surface and atmospheric conditions.

Conference Presentation

Citation Download Citation

Alexander Radkevich "An approach to retrieve BRDF from satellite and airborne measurements of surface-reflected radiance based on decoupling of atmospheric radiative transfer and surface reflection", Proc. SPIE 11152, Remote Sensing of Clouds and the Atmosphere XXIV, 111520D (9 October 2019); https://doi.org/10.1117/12.2530662

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available