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Long-term validation of GOMOS, MIPAS and Sciamachy ozone and temperature profiles by the Envisat Quality Assessment with Lidar (EQUAL) project

Yasjka Meijer(1), J.-L. Baray(2), G.E. Bodeker(3), H. Cluade(4), K.H. Fricke(5), P. Gathen, von der(6), S. Godin-Beekmann(7), G. Hansen(8), P. Keckhut(9), T. Leblanc(10), D.E. Lolkema(1), I.S. McDermid(10), H. Nakane(11), S. Pal(12), P. Snoeij(13) and D.P.J. Swart(1)

(1) RIVM, Postbus 1, 3720 BA Bilthoven, Netherlands
(2) IPSL, Uni. La Reunion, St. Denis, France
(3) NIWA, PB 50061, Lauder, New Zealand
(4) DWD, Station, Hohenpeissenberg, Germany
(5) Uni. Bonn, (Esrange), Bonn, Germany
(6) AWI, Polar and Marine Research, Potsdam, Germany
(7) CNRS, SA, Paris, France
(8) NILU, (Alomar), Tromso, Norway
(9) CNRS, UniversiteĀ“ de Versailles Saint-Quentin, Verrieres-le-Buisson, France
(10) JPL, Table Mountain, Wrightwood (CA), United States
(11) NIES, NDSC, Tsukuba, Japan
(12) SAAI, For MSC, Toronto, Canada
(13) ESA, ESTEC, Noordwijk, Netherlands


The Envisat Quality Assessment with Lidar (EQUAL) project supports the long-term validation of ENVISAT's three atmospheric chemistry instruments. This ESA funded project started in 2004 and involves eleven, and later possibly thirteen, lidar stations around the world measuring ozone and temperature profiles. The participating stations are (from north to south) located in Eureka, Ny Alesund, Alomar, Esrange, Hohenpeissenberg, OHP, Tsukuba, Table Mountain, Mauna Loa, La Reunion, and Lauder. In 2006 two additional lidar stations, located in Dumont dā€™Urville (Antacrtic) and Rio Gallegos (Southerrn Argentina), are likely to join the consortium. Over the period 2002-2005 in total over 3500 lidar data files have been submitted (in HDF) and are available in the correlative database at NILU (Norway). Besides the required coordination of the data acquisition, this project involves dedicated validation activities to assess the data quality. The data under investigation are the ozone and temperature profiles of the Global Ozone Monitoring by Occultation of Stars (GOMOS), Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) instruments. The main focus will be on the quality of the operational ESA products, but the focus might sometimes be changed toward products of scientific institutes exploring retrieval algorithms of (potential) future operational products. The vast amount of lidar data covering several latitudinal regions allows the analysis for possible dependencies of these data on several geophysical (e.g., latitude) and observational (e.g., star characteristics) parameters. In this presentation the main analysis results will be presented for each of the six ENVISAT data products under inverstigation.


Workshop presentation

Full paper

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry