SCIAMACHY Processor Releases

Processor Releases

The following sections report the history of the SCIAMACHY Level 1 and Level 2 processors' releases, and detail configurations and the related documentation.

SCIAMACHY Level 1b Processor Releases

Processor Version   DPM ATBD IODD Prod Spec Processor Updates Operational Switch Date
8.02 Prototype 6A 6 8 3M Processing baseline version 8.02 fixes a bug for corrupted or incomplete states within Level 0 products, which were incorrectly transferred into Level 1b data. Minor algorithms changes, and revised consistency checks on measurement states are implemented with respect to version 8.01.
Processor version 8.02 was used in the latest
SCIAMACHY reprocessing campaign.
Phase F
8.01 Prototype 6 6 8 3m

Major algorithm improvements with respect to version 7.04 are the following:

  • The stray light correction based on a matrix approach is extended to channels 3-8.
  • The memory effect correction (MEC) for limb data is improved, correcting the estimate for the signal of the reset readout at new tangent heights. This is especially significant for measurements above 40 km tangent height.
  • The scaling factor used for the non-linearity correction (NLC) for co-added data is corrected. In the previous version NLC was wrongly calculated, when PMD signals were affected by high noise.
  • The hot pixel correction for limb dark measurements is completely revised.
  • The polarisation correction for occultation is switched off, since no reliable calibration data exist for this case, and no significant amount of polarisation is expected in this mode.
  • States used for dark calculation are selected in the configuration file. Only dark states with pixel exposure times between 0.125 and 1 second are used.
  • The radiometric calibration uses a new approach: a physical model of the scanner unit including contamination layers (the scan mirror model).
  • Radiometric and polarisation key data are updated from on-ground calibrations and adapted for the scan mirror model.
  • A correction for the instrument scan-angle dependent degradation is calculated using a scan mirror model.
  • Degradation is now corrected in the Level 1 processing (m-factor application) as part of the radiometric calibration.
  • Mean PMD values are now corrected for degradation.

Processor version 8.01 was used in the latest SCIAMACHY reprocessing campaign.

Phase F
7.04 IPF 5 5 7 3L For the Envisat 2010+ mission extension, requiring the lowering of the satellite's orbit, IPF 7.04 was developed without introducing evolution aspects in the algorithm.  Only the ESA CFI software library was updated to version 5.8.1 (Linux 32 bit), capable to handle measurements for both the old and the new satellite's orbit. Jun 2010
7.03 IPF 5 5 7 3L
  • New degradation correction using m-factors.
  • Introduction of stray light correction using matrix approach for channel 2
  • Mesospheric Limb Measurements performed for 30 orbits every month on two separate days. State ID 55 included in Limb MDS. Measurements not processed to Level 2 products.
  • Software patch for scanner encoder values.
Feb 2010
7.02 IPF 5 5 7 3K   not operated
7.00 IPF 5 5 6A 3K   not operated
6.05 IPF 4B 4 6A 3K No evolution introduced, but processor was ported from AIX to LINUX operating system. Sep 2009
6.04 IPF 4B 4 6 3K   not operated
6.03 IPF 4B 4 6 3K
  • New pointing correction with new SCI_LI1_AX.
  • Update of ESA CFI software to version 5.06.
  • Correction of a bug (ENVI-NCR-06-1739), impacting Leakage GADS (channels 6-8) for consolidated data processing.
Jul 2007
6.02 IPF 4B 4 6 3K
  • Polarization correction factors now different from 0
  • Corrected order of SMR spectra in Sun Reference ADS
  • Corrected sign of solar mean reference spectra in New Sun Reference DS.
Jun 2006
6.01 IPF       3K
  • Improved parameterization of the Memory effect for channels 1 to 5
  • New correction for Non-Linearity effect in infrared channels
  • Improved key data for the radiometric calibration of all channels
  • Calibrated and un-calibrated Solar spectra provided
  • Orbital dependency of channels 6 to 8 leakage calculated; applied only to channel 8
  • Pointing accuracy improved through the usage of the Envisat Restituted Attitude auxiliary files in the off-line processing
  • Decontamination flag added to SPH
May 2006
5.04 IPF       3H
  • Code adaptations to solve performance problems encountered during reprocessing.
  • Corrected polarization ratio calculation to remove radiance discrepancies up to 1% between prototype and operational processor.
  • Memory leaks eliminated
  • Bugs fixed to avoid Level 1b processing crashes
Aug 2004



SCIAMACHY Level 2 Processor Releases

Processor Version   DPM ATBD IODD Prod Spec Processor Updates Operational Switch Date
6.01 Prototype   2B 6 3M Fixing bug for O3 limb retrieval Phase F Full mission reprocessing
6.00 Prototype   2 6 3M
  • Additional Nadir MDS for CH4, HCHO, CHOCHO columns.
  • Additional MDS for Tropospheric NO2.
  • Noctilucent clouds (NLCs) from limb measurements;
  • Improved AAI (now using retrieved ozone values instead of formerly used climatological ones);
  • Cloud fraction (cloud/ice separation introduced).
  • Ozone profiles retrieval extended up to 65 km.
  • The instrument degradation correction (m-factor) is now performed in the Level 0-1b processing

Phase F

DDS generation only

5.02 Prototype   1A 5A 3L

Optimized retrieval settings leading to a significant quality improvement for:

  • Nadir SO2 Vertical Column Density (fix for background database; max-SZA cut-off decreased from 89 to 80 deg.; fix quality flag; earthshine stretch implemented; reference Ring spectrum improved; change in eta reference spectrum).


  • Nadir OClO Slant Column Density (correction of polynomial degree used in DOAS fit; SZA cut-off changed from 95 to 92 deg.).
  • Nadir CO Vertical Column Density (introduction of a linear wavelength-dependent wavelength shift spectral correction).
Oct 2011
5.01 Prototype     5 3L
  • Starting with processor version 5.01, a new limb retrieval grid of 27 tangent altitudes was adopted instead of the 19 values used previously.
  • Additional Nadir MDS for SO2, BrO, H2O, OClO, and CO columns.
  • Additional Limb MDS for BrO profiles.
  • Limb Cloud MDS contains indicators for cloud presence and type (water clouds, PSCs and NLCs).
Feb 2010
4.00 Prototype     4H n/a
  • Implementation of SO2 nadir slant columns.
  • Implementation of BrO nadir slant columns.
  • New Aerosol Absorption Index (AAI) algorithm.
  • M-factor application in ozone retrieval.
  • Improved calibrations for NO2 nadir retrievals using not radiometrically calibrated Earthshine data and SMR from ASM diffuser (ID 'A0').
  • NO2 and O3 limb profile retrievals improved adopting a new forward model (using Picard iteration) and optimised settings.
Not operated
3.01 Prototype




  4G 3K
  • Updated SACURA cloud algorithm.
  • Removed offset applied to NO2 slant column processing.
  • Number of retrieved profiles per state set from one to four.
  • Cloud and Aerosol MDS filled with next valid value instead of being set to zero
  • Molecular Ring correction applied on NADIR O3 slant column density.


Bugs fixed for:

  • Interchange of Pressure and Temperature values in LIMB MDS
  • Erroneous Cloud and Aerosol Quality Flags
  • AAI erroneously set to zero in Cloud and Aerosol MDS
  • Error estimate for NO2 profiles higher than expected
Oct 2007
3.00 Prototype     4G 3K
  • New Nadir UV/Visible algorithm for O3 and NO2 based on the GOME Data Processor Version 4.0.
  • Nadir UV/Visible algorithm for cloud-top height and cloud optical thickness based on SACURA.
  • Limb UV/Visible products: Stratospheric O3 and NO2 profiles.
  • Improved pointing using Envisat Restituted Attitude information in consolidated product
May 2006
2.5 Prototype       3H First operational version of SGP processor replacing IPF. Jan 2005