MERIS Level 1 Radiometric Processor - MERIS Smile Correction Algorithm Specification

Auxiliary Data Files

The MERIS Smile Correction uses three different sets of auxiliary data files for processing. All of them are flat text files:

  1. For all MERIS L1b products: band_info.txt
  2. For MERIS L1b full resolution products: central_wavelen_fr.txt, sun_spectral_flux_fr.txt
  3. For MERIS L1b reduced resolution products:central_wavelen_rr.txt, sun_spectral_flux_rr.txt

band_info.txt

This file contains a header line followed by 15 lines associated with each MERIS band. The header line explains the parameters contained in this file. The columns are theoretical band wavelength in nm solar spectral flux in LU for the theoretical band wavelength
1 band the one-based band index (ignored)
2 switch_land whether or not to perform reflectance correction over land
3 lower_land lower, one-based band index to be used for correction over land
4 upper_land upper, one-based band index to be used for correction over land
5 switch_water whether or not to perform reflectance correction over water
6 lower_water lower, one-based band index to be used for correction over water
7 upper_water upper, one-based band index to be used for correction over water
8 lam_theo
9 E0_theo
The Smile Correction always ignores the header line and the first column.

central_wavelen_fr.txt / central_wavelen_rr.txt

This files contain a header line followed by 3700 (FR) resp. 925 (RR) lines associated with each detector containing the zero-based detector index in the first column and the central wavelengths (in nm) for each MERIS band.
The Smile Correction always ignores the header line and the first column.

sun_spectral_flux_fr.txt / sun_spectral_flux_rr.txt

This files contain a header line followed by 3700 (FR) resp. 925 (RR) lines associated with each detector containing the zero-based detector index in the first column and the solar spectral fluxes (in LU) for each wavelength for each MERIS band.
The Smile Correction always ignores the header line and the first column.