OBJECTIVE EVALUATION OF THE IMPACT OF RAL GOME OZONE PROFILES ON MET OFFICE 3D-VAR ANALYSES

• Main Authors: R. Dragani, S. Migliorini, A. Geer, C. Peubey, W. Lahoz, R. Brugge, R. Bannister, R. Siddans, B. Kerridge
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarc*; Antarctica
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.380.3905; http://earth.esa.int/workshops/salzburg04/papers_posters/4D3_dragani_501.pdf

A new retrieval scheme has been developed to produce height-resolved ozone profiles spanning the troposphere and stratosphere from measurements made by the Global Ozone Monitoring Experiment (GOME). Comparison of those profiles with ozone sonde data reveals good agreement throughout the troposphere and stratosphere, with significant improvement over climatological information in the lower stratosphere. The present paper determines whether the new information contained in the GOME ozone profiles can improve global analyses of ozone produced by a data assimilation system when they are used in combination with ozone profiles derived from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) measurements. The data assimilation system is the 3D-VAR system used by the UK Met Office. Two classes of experiment were run for the period September 2002, when there was an exceptional split of the ozone hole over Antarctica. A control experiment included ozone data from MIPAS only; the second experiment included, in addition, GOME ozone profiles. A statistical analyses is used to determine the impact of adding the GOME data. An objective comparision of the results of these experiments is also made with independent (unassimilated) data from ozonesondes. 1.