Towards the short wavelength region of GOME, the ozone
absorption and Rayleigh scattering increases several order of
magnitudes. The shorter the wavelength, the higher the altitude is
where the information content of ozone becomes maximum. Using an
Optimal Estimation inversion, for instance, ozone profiles can
be derived. A-priori information on ozone profiles, for instance, from
a monthly ozone climatology, is included to stabilise (or in
mathematical terms: regularise) the spectral fit.
This graphics shows an ozone sonde profile
(dashed line) from the Meteorological Observatory of the German
Weather Service (DWD) at Hohenpeissenberg (49N) together with a GOME
profile (solid line) measured the same day (21 March 1997) within 500
km distance from the sonde launch site. The vertical resolution of the
GOME profile is about 6 km in the lowermost stratosphere and increases
to about 10 km at higher altitudes and in the troposphere (below 10 km
altitude). In-situ measurements from the sondes provide ozone
concentrations about every 200 m (depending on ascent
During the period July 1996-June
1997 about 50 collocated measurements from GOME and ozone sondes at
Hohenpeissenberg are compared in this figure. Because of the limited
vertical resolution of GOME it is better to compare subcolumn amounts
(here 10 km wide layers). Good agreement between sondes and GOME
observations were confirmed by similar comparisons with other sonde
stations in Europe at mid- to high latitudes. The annual dynamic
variability is well captured by GOME, however some deviations may be
due to different air masses which are probed by both instruments
(large GOME ground pixel (960X100 km2) versus in-situ sonde
An alternative to the above mentioned optimal
estimation scheme is a neural network retrieval scheme. This has been
developed in collaboration with ZSW Stuttgart. It can be also
applied to retrieve total ozone. The major advantage of the neural
network is its high speed (no iteration necessary) that makes it
suitable for real time applications.
With the financial support of the European Space
Agency (ESA Project GOME Total Ozone Retrieval Development
GOTOCORD) a novel total ozone retrieval algorithm will be
developed. This algorithm uses the weighting function DOAS approach
(WFDOAS). The major difference to standard DOAS is the spectral
fitting of weighting functions rather than absorption
cross-section. Vertical column densities are directly retrieved
avoiding the use of airmass factors (AMF) for slant column density
conversion as in the current operational retrieval scheme. The Version 1 of WFDOAS data has now been released.
Scientific Case Studies
Examples for the application of GOME ozone profiles
and columns for interpreting dynamic (transport) and chemical changes
in ozone are investigations of ozone
minihole events and chemical ozone loss in the Arctic polar vortex
(see poster presented at the
Palermo THESEO2000-SOLVE Science Meeting, 24 September - 29 September
If you have any questions or need more information,
K. Bramstedt, K.-U. Eichmann, M. Weber, R. Hoogen, V. Rozanov, and
J.P. Burrows, Ozone depletion in the Arctic spring calculated from
GOME Ozone Profiles, European Symposium on
Atmospheric Measurements from Space, Proc. ESAMS'99, ESA-WPP-161,
A. Bracher, M. Weber, K. Bramstedt, S. Tellmann, J. P. Burrows,
Long-term global measurements of ozone profiles by GOME validated with
SAGE II considering atmospheric dynamics, J. Geophys. Res. 109, D20308,
doi 10.1029/2004JD004677, 2004.
- A. Bracher, M. Weber, K. Bramstedt, M. Coldewey-Egbers, L. N. Lamsal, J. P.
Global satellite validation of SCIAMACHY O3 columns with GOME WFDOAS,
Atmos. Chem. Phys. Discuss. 5, 795-813, 2005.
K. Bramstedt, K.-U. Eichmann, M. Weber, V. Rozanov, and J. P. Burrows,
GOME ozone profiles: A global validation with HALOE measurements,
Adv. Space Res. 29, 1637-1642, 2002.
K. Bramstedt, J. Gleason, D. Loyola, W. Thomas, A. Bracher, M. Weber,
and J. P. Burrows, Comparison of total ozone from the satellite
instruments GOME and TOMS with measurements from the Dobson network
1996-2000, Atmospheric Chemistry and Physics 3, 1409-1419, 2003.
- H. Bremer, M. von König, A. Kleinböhl, H. Küllmann,
K. Künzi, K. Bramstedt, J. P. Burrows, K.-U. Eichmann, M. Weber,
A. P. H. Goede, Ozone depletion observed by ASUR during the Arctic
Winter 1999/2000, J. Geophys. Res. 107, 8277,
- K.V. Chance, J.P. Burrows, D.Perner, and W. Schneider, Satellite
measurements of atmospheric ozone profiles from ultravisible
measurements in the nadir geometry: a potential method to retrieve
tropospheric ozone, J. Quant. Spectrosc. Radiat. Transfer 57, 467-476,
- M. Coldewey-Egbers, M., M. Weber, M. Buchwitz, and J.P. Burrows,
Application of a modified DOAS method for total ozone retrieval from
GOME data at high polar latitudes, Adv. Space Res. 34, 749-753, 2004.
- M. Coldewey-Egbers, M. Weber, L. N. Lamsal, R. de Beek,
M. Buchwitz, J. P. Burrows,
Total ozone retrieval from GOME UV
spectral data using the weighting function DOAS approach,
Atmos. Chem. Phys. 5, 5015-5025, 2005.
- R. de Beek, M. Weber, V.V. Rozanov, A. Rozanov, A. Richter, and
J.P. Burrows, Trace gas column retrieval - An error study for GOME-2,
Adv. Space Res. 34, 727-733, 2004.
- K.-U. Eichmann, K. Bramstedt, M. Weber, R. Hoogen, V.V. Rozanov,
and J.P. Burrows, Structure of ozone mini-holes from GOME, European
Symposium on Atmospheric Measurements from Space, Proc. ESAMS'99,
ESA-WPP-161, 231-236, 1999.
- K.-U. Eichmann, K. Bramstedt, M. Weber, V.V. Rozanov, R. Hoogen
and J.P. Burrows, O3 profiles from GOME satellite data -
II: Observations in the Arctic spring 1997 and 1998,
Physics and Chemistry of the Earth 24, 453-457, 1999.
- K.-U. Eichmann, M. Weber, K. Bramstedt, and J.P. Burrows, Ozone
depletionin the NH winter/spring 1999/2000 as measured by GOME-ERS2,
J. Geophys. Res. 107, 8280, doi:10.1029/2001JD001148, 2002.
- G. Hansen, K. Bramstedt, V. Rozanov, M. Weber, and J.P. Burrows,
Validation of GOME ozone profiles by means of the ALOMAR ozone lidar,
Annales Geophysicae 21, 1879-1886, 2003.
- R. Hoogen, V.V. Rozanov, J.P. Burrows, Ozone Profiles
from GOME Satellite Data: Algorithm Description and First
Validation, J. Geophys. Res., 104,
- R. Hoogen, V.V. Rozanov, K. Bramstedt, K.-U. Eichmann, M. Weber,
and J.P. Burrows, Ozone profiles from GOME satellite data-I:
Comparison with ozonesonde measurements,
Physics and Chemistry of the Earth 24, 447-452, 1999.
L.N. Lamsal, M. Weber, S. Tellmann, and J. P. Burrows, Ozone column
classified climatology of ozone and temperature profiles based on
ozonesonde and satellite data, J. Geophys. Res., 109, D20304,
M.D. Müller, A. Kaifel, M. Weber, J.P. Burrows, A new method
for retrieving total ozone from GOME data, Appl. Opt. 41, 5051-5058,
- M.D. Müller, A.K. Kaifel, M. Weber, S. Tellmann, J.P. Burrows,
D. Loyola, Ozone profile retrieval from GOME data using a neural
network approach (NNORSY), J. Geophys. Res. 108, 4497,
- A. Richter, F. Wittrock, M. Weber, S. Beirle, S. K¿l, U. Platt,
T. Wagner, W. Wilms-Grabe, and J. P. Burrows, GOME
observations of stratospheric trace gas distributions
during the splitting vortex event in the Antarctic winter
2002 Part I: Measurements,
J. Atmos. Sci. 62, 778-785, 2005
C. von Savigny, A. Rozanov, H. Bovensmann, K.-U. Eichmann, S. Noel,
V. V. Rozanov, B.-M. Sinnhuber, M. Weber, J. P. Burrows, J. Kaiser,
The ozone hole break-up in September 2002 as seen by SCIAMACHY on
ENVISAT, J. Atmos. Sci., accepted, 2004.
- B.-M. Sinnhuber, M. Weber, A. Amankwah, and J.P. Burrows, Total
ozone during the unusual Antarctic winter of 2002, Geophys. Res.
Lett. 30, 1850, doi:10.1029/2002GL016798, 2003.
- S. Tellmann, S., V.V. Rozanov, M. Weber, and J.P. Burrows,
Improvements in the tropical ozone profile retrieval from GOME
UV/vis nadir spectra, Adv. Space Res. 34, 739-743, 2004.
- M. Weber, K.-U. Eichmann, F. Wittrock, K. Bramstedt, L. Hild,
A. Richter, J.P. Burrows, and R. Müller, The cold Arctic winter
1995/96 as observed by the Global Ozone Monitoring experiment GOME and
HALOE: Tropospheric wave activity and chemical ozone loss,
Q. J. Roy. Meteor. Soc. 128, 1293-1319, 2002.
M. Weber, S. Dhomse, F. Wittrock, A. Richter, B.-M. Sinnhuber, and
J.P. Burrows, Dynamical Control of NH and SH Winter/Spring Total Ozone
from GOME Observations in 1995-2002, Geophys. Res. Lett., 30, 1853,
M. Weber, L. N. Lamsal, M. Coldewey-Egbers, K. Bramstedt, J. P. Burrows,
Pole-to-pole validation of GOME WFDOAS total ozone with groundbased
data, Atmos. Chem. Phys. 5, 1341-1355, 2005.