Minimize Aerosol Retrieval

Aerosol properties are retrieved pixel-wise for the SYN averaged data. The algorithm can consider up to 40 different aerosol models, but it is sufficient to use a subset of aerosol models only. The aerosol models actually used for the retrieval are defined in auxiliary data.

The pixel-wise retrieval of aerosol properties is illustrated in the figure below.

Logical flow of the SYN Level-2 Aerosol Retrieval

The retrieval algorithm employs the Brent and Powell methods for univariate and multivariate minimisation, respectively.

Aerosol properties for pixels in the SYN averaged grid where the retrieval algorithm failed or was not applicable (i.e. water, clouds) have to be filled with valid data from neighbouring pixels. For implementation and to avoid stripes resulting from the filling process, it is recommended to keep the complete SYN averaged grid of pixels in random access memory.