Evaluating a new homogeneous total ozone climate data record from GOME/ERS-2, SCIAMACHY/Envisat and GOME-2/MetOp-A

M. E. Koukouli (1) , Christophe Lerot (2) , José Granville (2) , Florence Goutail (3) , Jean-Christopher Lambert (2) , Jean-Pierre Pommereau (3) , D. Balis (1) , I. Zyrichidou (1) , Michel van Roozendael (2) , M. Coldewey-Egbers (4) , D. Loyola (4) , G. Labow (5) , S. Frith (5) , R. Spurr , C. Zehner (6)

1 Laboratory of Atmospheric Physics [Thessaloniki]
2 BIRA-IASB - Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique
3 STRATO - LATMOS
4 IMF - DLR Institut für Methodik der Fernerkundung / DLR Remote Sensing Technology Institute
5 GSFC - NASA Goddard Space Flight Center
6 ESRIN - European Space Research Institute

The European Space Agency's Ozone Climate Change Initiative (O3-CCI) project aims at producing and validating a number of high-quality ozone data products generated from different satellite sensors. For total ozone, the O3-CCI approach consists of minimizing sources of bias and systematic uncertainties by applying a common retrieval algorithm to all level 1 data sets, in order to enhance the consistency between the level 2 data sets from individual sensors. Here we present the evaluation of the total ozone products from the European sensors Global Ozone Monitoring Experiment (GOME)/ERS-2, SCIAMACHY/Envisat, and GOME-2/MetOp-A produced with the GOME-type Direct FITting (GODFIT) algorithm v3. Measurements from the three sensors span more than 16 years, from 1996 to 2012. In this work, we present the latest O3-CCI total ozone validation results using as reference ground-based measurements from Brewer and Dobson spectrophotometers archived at the World Ozone and UV Data Centre of the World Meteorological Organization as well as from UV-visible differential optical absorption spectroscopy (DOAS)/Système D′Analyse par Observations Zénithales (SAOZ) instruments from the Network for the Detection of Atmospheric Composition Change. In particular, we investigate possible dependencies in these new GODFIT v3 total ozone data sets with respect to latitude, season, solar zenith angle, and different cloud parameters, using the most adequate type of ground-based instrument. We show that these three O3-CCI total ozone data products behave very similarly and are less sensitive to instrumental degradation, mainly as a result of the new reflectance soft-calibration scheme. The mean bias to the ground-based observations is found to be within the 1 ± 1% level for all three sensors while the near-zero decadal stability of the total ozone columns (TOCs) provided by the three European instruments falls well within the 1–3% requirement of the European Space Agency's Ozone Climate Change Initiative project.

Mots clés: GOME-2; Dobson; SCIAMACHY; Brewer; total ozone; validation

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]; Climatologie

M. E. Koukouli, Christophe Lerot, José Granville, Florence Goutail, Jean-Christopher Lambert, et al.. Evaluating a new homogeneous total ozone climate data record from GOME/ERS-2, SCIAMACHY/Envisat and GOME-2/MetOp-A. Journal of Geophysical Research: Atmospheres, 2015, 120 (23), pp.12296-12312. ⟨10.1002/2015JD023699⟩. ⟨insu-01240107⟩