Sentinel-2 level 2a product prototype processor: research and design aspects

The contribution covers research and development aspects concerning a Sentinel-2 atmopsheric correction processor. The Sentinel-2 multispectral sensor acquires 13 optical channels from the deep blue (0.443 µm) up to the shortwave infrared (2.19 µm) spectral range. These multispectral data allows aerosol optical thickness, water vapor, cirrus, and bottom of atmospere reflectance estimation. Sensitivity analysis given simulated and real spectral data as wellas an estimation of the parameter set was done. The research outcome is documented in the algorithm theoretical basis document and implemented into an automatic batch processing chain. Scientific validation of the processor on synthetic and real data with in situ measurements finalizes the work