GOMOS O3, NO2, and NO3 observations in 2002–2008 1Finnish Meteorological Institute, Earth Observation, Helsinki, Finland
2Laboratoire Atmosphères, Milieux, Observations Spatiales, Université Versailles St.-Quentin, CNRS-INSU, Verrières-le-Buisson, France
3Institut d'Aéronomie Spatiale de Belgique, Brussels, Belgium
4ACRI-ST, Sophia Antipolis, France
5European Space Research Institute (ESRIN), European Space Agency, Frascati, Italy
Received: 18 December 2009 – Published in Atmos. Chem. Phys. Discuss.: 01 February 2010 Abstract. The Global Ozone Monitoring by Occultation of Stars (GOMOS) instrument
onboard the European Space Agency's ENVISAT satellite measures ozone, NO2,
NO3, H2O, O2, and aerosols using the stellar occultation method.
Global coverage, good vertical resolution and the self-calibrating
measurement method make GOMOS observations a promising data set for building
various climatologies and time series. In this paper we present GOMOS
nighttime measurements of ozone, NO2, and NO3 during six years
2002–2008. Using zonal averages we show the time evolution of the vertical
profiles as a function of latitude. In order to get continuous coverage in
time we restrict the latitudinal region to 50° S–50° N. Time
development is analysed by fitting constant, annual and semi-annual terms as
well as solar and QBO proxies to the daily time series. Ozone data cover the
stratosphere, mesosphere and lower thermosphere (MLT). NO2 and NO3 data
cover the stratosphere. In addition to detailed analysis of profiles we
derive total column distributions using the fitted time series.
Revised: 09 June 2010 – Accepted: 17 August 2010 – Published: 20 August 2010
The time-independent constant term is determined with a good accuracy (better
than 1%) for all the three gases. The median retrieval accuracy for the
annual and semi-annual term varies in the range 5–20%. For ozone the annual
terms dominate in the stratosphere giving early winter ozone maxima at
mid-latitudes. Above the ozone layer the annual terms change the phase which
results in ozone summer maximum up to 80 km. In the MLT the annual terms
dominate up to 80 km where the semiannual terms start to grow. In the
equatorial MLT the semi-annual terms dominate the temporal evolution whereas
in the mid-latitude MLT annual and semi-annual terms compete evenly. In the
equatorial stratosphere the QBO dominates the time development but the solar
term is too weak to be determined. In the MLT above 85 km the solar term
grows significantly and ozone has 15–20% dependence on the solar cycle. For
NO2 below 32 km the annual summer maxima dominates at
mid-latitudes whereas in the equatorial region a strong QBO prevails.
In northern mid-latitudes a strong solar term appears in the upper stratosphere. For
NO3 the annual variation dominates giving rise to summer maxima. The
NO3 distribution is controlled by temperature and ozone.
Citation: Kyrölä, E., Tamminen, J., Sofieva, V., Bertaux, J. L., Hauchecorne, A., Dalaudier, F., Fussen, D., Vanhellemont, F., Fanton d'Andon, O., Barrot, G., Guirlet, M., Fehr, T., and Saavedra de Miguel, L.: GOMOS O3, NO2, and NO3 observations in 2002–2008, Atmos. Chem. Phys., 10, 7723-7738, doi:10.5194/acp-10-7723-2010, 2010.