Demonstration and validation of the φ‐IASI inversion scheme with NAST‐I data

The physical forward/inverse scheme φ‐IASI has been applied to the retrieval of atmospheric vertical profiles of temperature, water vapour and ozone by inverting high spectral infrared observations recorded by the NAST‐I Fourier Transform Spectrometer. For the retrieval exercise we have used clear‐sky spectra recorded over the sea surface on the night of 9–10 September 2004, during the Italian phase of the EAQUATE field campaign. During the campaign NAST‐I flew on board the NASA Proteus aircraft at an altitude of 15 km. Retrievals have been compared to radiosonde observations, profiles from the ECMWF analysis and AIRS level 2 products. While providing a basis for the validation of the φ‐IASI inversion scheme, the retrieval exercise has also demonstrated (i) the NAST‐I ability to accurately detect H 2 O fine‐scale vertical features, and (ii) the good quality of the temperature and water vapour profiles from the ECMWF analysis. Copyright © 2007 Royal Meteorological Society