TOA Radiative products

ScaRaB-3 (Scanner for Radiation Budget) is an optical scanning radiometer devoted to the measurements of radiative fluxes at the top-of-atmosphere (TOA) in the shortwave and longwave domain, described in Chomette et al, 2010.The TOA albedo is also computed.

Level-2 products

The level-2 product contains instantaneous top-of-atmosphere fluxes and albedo at ScaRaB pixel scale.  The conversion between radiance and hemispherical flux is obtained with an algorithm based on an artificial neural network approach and is called SANN (ScaRaB Artificial Neural Network). You can find a description of this approach in Viollier et al. (2009).

In the level-2 products, the user can also find the unfiltered radiances for ScaRaB-3 deduced from the filtered radiances. The unfiletered radiances are obtained using computing scene dependent factor.

In Figure 1, we have the SANN Flux for one orbit on the 09 december 2011.

Figure 1: Example of instantaneous LW (top) and SW  L2 fluxes in Wm-2. 

Level-2B products

The Level 2-SANN product has also been projected (with a PSF approach, see gif et al. 2011) on a 1°x1° grid to create this L2-B product. In the last version (V2.01) of this product, there is also L2B products on a 0°5×0°5 grid.  The Figure 2 shows an example.  
Figure 2: TOA Longwave Fluxes Level 2B. 


Rémy Roca :

Olivier Chomette :

Patrick Raberanto :


Product Definition Document: Top Of the Atmosphere Fluxes & Albedo, L2 products derived from SCARAB (L2B output modified and additional 0°5 output –  UPDATED March 2019)

Level 1 products definition  (CNES documentation)


Gif, N., O. Chomette, and P. Raberanto, 2011: Co-location algorithms. Geophysical data projection using pixel point spread function.Megha-Tropiques Technical Memorandum n°2

Viollier, M., C. Standfuss, O. Chomette and A.Quesney 2009: Top-of-Atmosphere Radiance-to-Fluxconversion in the SW domain for the ScaRaB-3 instrument on Megha-Tropiques. J. Atmos. Oceanic Technol., 26, 2161-2171.

Chomette, O., P. Raberanto, and R. Roca: AMS_Manuscrit_Olivier-Chometteproceeding of the 13th Conference on Atmospheric Radiation, American Meteorological Society,  28 June – 2 July 2010, Portland, Oregon.