Improving SCIAMACHY Data
Task A of the project covers the improvement SCIAMACHY of the Level 1b degradation correction, with the aim to remove ozone trends from the SCIAMACHY Level 2 dataset that were introduced during the development of baseline version 9 (dataset not released). The correction is a pre-requisite for the generation of the FDRs and thus was exceptionally included in the FDR4ATMOS project. In task B (the generation of the FDRs) we will use the Level 1 data only as input. The FDR processing and resulting products will be done separately with the goal of Level 1 data usable for cross-instrument, long time series investigations.
The updated Level 0-1 Processor will include the following changes:
- An updated degradation correction to correct the Ozone trend
- The replacement of the old ESA CFI geolocation with a newer CFI library to enable multi-threading
The figure below shows the problem: Although the retrieval algorithm was not changed, the last implemented version of the SCIAMACHY processors showed an unphysical trend over the mission duration. The data product from this version were not released to the user community because of the drift.
In phase 1 of the project the degradation correction was improved and a quick test based on 1500 orbits distributed over the duration of the mission shows no longer a significant trend (see figure below). Testing and validation based on a larger data set of 5000 orbits is ongoing.
