Global Assessment of Reprocessed Envisat Altimetry V2.1 Wind and Wave Products
Abdalla, Saleh; Bidlot, Jean-Raymond; Janssen, Peter
ECMWF, UNITED KINGDOM

ESA has been committed to reprocess its past and present Earth Observation Missions of ERS and ENVISAT using the latest available algorithms and applications to produce longer and rather homogeneous time histories. Some of the reprocessing campaigns have already concluded while some are still ongoing.

The full-mission reprocessing of the ENVISAT Altimetry Level 2 data set V2.1 has already completed. The data covering the period from 30 September 2002 (orbit 3061-cycle 10) to 19 September 2010 (orbit 44643 cycle 92) have been made available by ESA. The reprocessing campaign was performed using the IPF version 6.04 (L1b) and CMA processor version 9.3 (L2) and the CNES GDR-C precise orbit products. Similar campaign has been going on for the reprocessing of the ERS altimetry products (REAPER Project).

At the same time, ECMWF has been carrying out a re-analysis project called ERA-Interim in preparation for the ERA-CLIM which has just started. ERA-Interim aims also towards producing a long-term rather homogeneous model data set using the best available model and data assimilation techniques at the start of the project.

The wind and wave products were assessed mainly against ERA-Interim and related model runs. Preliminary results of this effort were presented during the "20 Years of Progress in Radar Altimetry Symposium" last year. Further results will be shown especially the assessment against in situ data. Furthermore, several numerical experiments are being carried out in order to assess the impact of assimilating the reprocessed significant wave height data in the ECMWF wave model. The results of those experiments will be also presented.