TOSOMI algorithm version history
Henk Eskes and Ronald van der A, KNMI
The current version of the Sciamachy DOAS total ozone retrieval software "TOSOMI" is version 2.0.
It is almost identical to the GOME software "TOGOMI" version 2.0. TOSOMI and TOGOMI are
based on the OMI DOAS ozone column retrieval "OMDOAO3"
version notes, tosomi v2.0 (March 2011)
- FRESCO SC-v6 used
- Correction of the reading of surface reflectivity data
- Only version 7.03/7.04 level 1 files used
version notes, tosomi v0.43 (September 2008)
- Corrected temperature files used
- Only version 6.03 level 1 files used
version notes, tosomi v0.42 (March 2007)
- Data files polycoef_trs_scia.dat and polycoef_R1_scia.dat added for use by FRESCO+.
- FRESCO+ (SC-v5) replaces FRESCO SC-v4:
new sciaFrescoInterface.f90 (line 134-139, 195-209)
atmosphere_height from 50 km to 0 km (line 306)
- "writeOutputModule" header line updated
version notes, tosomi v0.4 (April 2006)
Cross sections: GOME Flight Model 98 cross sections are replaced by
effective cross sections based on Bass-Paur high resolution data
Bass, A.M., and Paur, R.J., Proc. Quadrennial Ozone Symp.,
Chalkidiki, Greece, Eds. C. Zefros and A. Ghazi. 1986
- Obsolete Cabannes correction factors removed
ComputeAmfModule.f90, line 252
- Added cycle command in "main.f90"
if (SciaPixelOut%amfQa < 0 ) cycle
This to skip the current observation in case the AMF is undefined,
e.g. because input parameters are out of range
added correction to compensate for the mismatch between the detector
readout time and the time at which the geometrical information is provided.
l 373, 374: definition of parameters
l 609-643 : implements the correction for the vza at satellite "dVzaSat"
For the evaluation of "isBackScan" the longitude/latitude information
and scanmirror angle is needed. The calculations for this have been
moved up (l 504-553).
- "writeOutputModule" header line updated
version notes, tosomi v0.33 (August 2005)
- The NASA toolbox has been replaced by a toolbox simulator module for
- The spectral reflectivity data base for the FRESCO algorithm is
upgraded to a 0.25 degree resolution map (by Nicolas Fournier)
- FrescoModule.f90, line 1585
Small bug fix in FRESCO
- sciaArrayDimsModule, line 21
Maximum number of SCIAMACHY pixels has been increased
- sciaFrescoInterface, line 262
Radiometric calibration fudge factor is changed from 1.25 to 1.2
for the FRESCO algorithm
- terrainHeightModule, line 12
The terrain height map resolution has increased to 0.25 degree
This is a new module
- A few error messages have been replaced by warnings
version notes, tosomi v0.32 (March 2004)
First validated data available on TEMIS
- A check is included on the version of the level 1 file.
"sciaReadModule": the angle conversion is now depending on L1_soft_version
- sciaUtilityModule: now contains extra routine
"RecoverSolarAnglesAtSat2"to convert angles from TOA to satellite.
- sciaReadModule: now includes a call to "check_data_validity", which checks the
range of the geolocation parameters
- sciaReadModule: A "fudge factor" of 1.19 is introduced to correct for
the SCIAMACHY missing radiance.
- The centre coordinates (longitude) of the pixels had a problem near the
date line. This coordinates was simply taken from the level-1 file and
copied to the output file.
For pixels on the date line, the longitude is now recomputed based on
the pixel corner coordinates:
sciaPixel%longitude(5) = sum(sciaPixel%longitude(1:4))*0.25
new output format (units 0.1 DU)
- The Sciamachy L1 reading libraries have been replaced.
The new library checks consistency between header and data, and
checks for empty files.
- In case of errors the program will produce an exit status = 1
"stop" statement replaced by "call exit(1)"
version notes, tosomi v0.31
A spherical geometrical air-mass factor is introduced to reduce
solar-zenith angle dependent interpolation errors in determining
the air-mass factor.
The input air-mass factor tables are updated and contain
The call to "computeAmfGeo" is replaced by "computeAmfGeoSpherical"
A new subroutine "computeAmfGeoSpherical" is added.
version notes, tosomi v0.3
Version 0.3 contains new lookup tables based on
semi-spherical DAK (Johan de Haan).
These tables replace the old ones:
The old plane-parallel lookup tables are still available as
The lookup table angles are defined at the Earth's surface
line 473: dAtmosphereHeight = 0.0d0
! The extra factor 1.25 accounts for problems with the
! radiometric calibration of Sciamachy
if ( firstcall ) then
print*,'sciaFrescoInterface WARNING: ',&
'scaling factor 1.25 applied to account for calibration errors'
A larger radiance error improves the Fresco performance, factor 0.005->0.05
A 7-line header is added to the data file, with processor version + authors
fields "product" and "soft_version" added to "SciaL1RadGenType"
contains extra field "SZA_MAX" set to 85.0 degree
reads the variable "opfData%szaMax"
variable "opfData%szaMax" added
implements check on the solar zenith angle - "szaMax"
extra subroutines "asin_" and "acos_" are defined to avoid NaNs due
to over/underflow of the argument. These alternative routines are used
in the angle manipulation subroutines.
Extra output flag value "xflag=5" introduced to intercept errors
in "gaussjf" related to singular matrices. Numerical recipes subroutine
now passes it's error by the variable "istatus"
An extra variable has been added to "acceptFrescoRetrieval" to account
for the new Fresco error warning.