AMC-DOAS
DOAS
SCIAMACHY
GOME
AMC-DOAS Water Vapour Data Products: Release Notes
Version 1.0 Version 0.9.1 and earlier
Version 1.0
- The retrieval uses an updated radiative transfer data base which is based on HITRAN2004.
- The calculation of errors has been updated; it now also
considers a
correction factor for unweighted data.
- GOME water vapour data are based on fully calibrated
consolidated Level 1 products only.
- The SCIAMACHY water vapour data are mainly derived from the SCIAMACHY reprocessed Level 1b V5 data set. Gaps in this data set have been filled (if possible) by NRT data of either V5 or V6 (since May 2006).
- In the extraction of the SCIAMACHY Level 1b radiances only memory effect correction, dark current correction and wavelength calibration are applied.
- All SCIAMACHY data have been processed using an
uncalibrated ASM
diffuser solar
reference spectrum. When no actual ASM diffuser spectrum was available
(like for
2002 data), the ASM diffuser spectrum of 9 April 2003 (also provided in
the
Level 1b product) was used. Therefore the quality of the 2002 SCIAMACHY
water vapour data is slightly reduced compared to later years.
- The Doppler shift for the SCIAMACHY solar reference spectrum is read from the Level 1b product.
- The status flag in the SCIAMACHY water vapour product is
used.
- Note: The combination of the new HITRAN data base results in typically smaller water vapour columns as in previous versions. This is especially true for SCIAMACHY data which are additionally based on updated spectral data.
Version 0.9.1 and
earlier
- GOME water vapour data are based on fully calibrated
consolidated Level 1 products only.
- The SCIAMACHY water vapour data are derived from both
SCIAMACHY NRT and
consolidated Level 1b data products of Versions 4 and 5.
- All SCIAMACHY data have been processed using a dedicated solar reference spectrum based on SCIAMACHY ESM diffuser measurements provided by ESA.
- A fixed Doppler shift for the SCIAMACHY solar reference spectrum is considered (0.01 nm at 500 nm).
- For the SCIAMACHY radiances, all calibration steps have been switched on during the extraction of the L1c product except polarisation correction.
- The status flag in the SCIAMACHY product is currently unused.
More information is given in the Algorithm Description and the Product Specification Document.
