Pathfinder product: Satellite-based aerosol composition assimilated into MATCH/DLR model

An aerosol retrieval method called Synergetic Aerosol Retrieval (SYNAER) applied to MetOp instruments AVHRR/GOME-2 was combined with a chemical transport model MATCH/DLR with the help of an advanced data assimilation procedure. Based on Desroziers et al., 2001 newly adapted background and observation error covariance matrices were used to characterize the relative weighting of data and model in this case study.

The first column in the image consists of SYNAER-MetOp aerosol optical depth values at 550 nm for four major aerosol components mineral dust, sea salt, soot and water soluble aerosol (from upper picture to down correspondingly). The respective MATCH/DLR model output with 1.9°-horizontal resolution for these four components is shown in column 2 (prior to) and in column 3 (after) data assimilation of the SYNAER data. The last column shows the increments in aerosol optical depth between original MATCH/DLR and MATCH/DLR-SYNAER assimilation values. Increments are per setup of this study equal to zero (green colour in last column), where no SYNAER observation is in the neighbourhood. A slight increase of sea salt and water soluble aerosol optical depth values is monitored, whereas mineral dust shows regional decrease and increase and soot is not altered by the available SYNAER dataset at this date.

For further information and/or questions, please contact wdc@dlr.de.