Error consistency analysis scheme for infrared ultraspectral sounding retrieval error budget estimation

Abstract

Great effort has been devoted towards validating geophysical parameters retrieved from ultraspectral infrared radiances obtained from satellite remote sensors. An error consistency analysis scheme (ECAS), utilizing fast radiative transfer model (RTM) forward and inverse calculations, has been developed to estimate the error budget in terms of mean difference and standard deviation of error in both spectral radiance and retrieval domains. The retrieval error is assessed through ECAS without relying on other independent measurements such as radiosonde data. ECAS establishes a link between the accuracies of radiances and retrieved geophysical parameters. ECAS can be applied to measurements from any ultraspectral instrument and any retrieval scheme with its associated RTM. In this manuscript, ECAS is described and demonstrated with measurements from the MetOp-A satellite Infrared Atmospheric Sounding Interferometer (IASI). This scheme can be used together with other validation methodologies to give a more definitive characterization of the error and/or uncertainty of geophysical parameters retrieved from ultraspectral radiances observed from current and future satellite remote sensors such as IASI, the Atmospheric Infrared Sounder (AIRS), and the Cross-track Infrared Sounder (CrIS).

Acknowledgements

IASI L1C data are provided by the Unified Meteorological Archival and Retrieval Facility (UMARF) of EUMETSAT. The fast cloud radiative transfer model was provided by Dr. Ping Yang of Texas A&M University. This research is supported by NASA Langley Research Center and NASA Headquarters. We would like to acknowledge support from NASA Headquarters Research Division Director Dr. Jack Kaye, and to extend our appreciation to the anonymous reviewers for their suggestions.