Retrieval of Surface Reflectance using SACRS2: a Scheme for Atmospheric Correction of ResourceSat-2 AWiFS data
Other literature type
Pandya, M. R.
Pathak, V. N.
Shah, D. B.
Singh, R.. P
(issn: 2194-9034, eissn: 2194-9034)
The Indian Remote Sensing (IRS) satellite series has been providing data since 1988 through various Earth observation missions.
Before using IRS data for the quantitative analysis and parameter retrieval, it must be corrected for the atmospheric effects because
spectral bands of IRS sensors are contaminated by intervening atmosphere. Standard atmospheric correction model tuned for the IRS
sensors was not available for deriving surface reflectance. Looking at this gap area, a study was carried out to develop a physicsbased
method, called SACRS2- a Scheme for Atmospheric Correction of Resourcesat-2 (RS2) AWiFS data. SACRS2 is a
computationally fast scheme developed for correcting large amount of data acquired by RS2-AWiFS sensor using a detailed radiative
transfer model 6SV. The method is based on deriving a set of coefficients which depend on spectral bands of the RS2-AWiFS
sensor through thousands of forward signal simulations by 6SV. Once precise coefficients of all the physical processes of
atmospheric correction are determined for RS2-AWiFS spectral bands then a complete scheme was developed using these
coefficients. Major inputs of the SACRS2 scheme are raw digital numbers recorded by RS2-AWiFS sensor, aerosol optical thickness
at 550 nm, columnar water vapour content, ozone content and viewing-geometry. Results showed a good performance of SACRS2
with a maximum relative error in the SACRS2 simulations ranged between approximately 2 to 7 percent with respect to reference
6SV computations. A complete software package containing the SACRS2 model along with user guide and test dataset has been
released on the website (www.mosdac.gov.in) for the researchers.