Infrared Satellite Retrievals in the Presence of Stratospheric Aerosol

Abstract

The presence of stratospheric aerosol can bias the results of infrared satellite retrievals of sea surface temperature (SST) and total precipitable water (TPW). In the case of linear SST retrieval using the Along Track Scanning Radiometer (ATSR), on the ESA European remote-sensing satellites, constant coefficients can be found that give negligible bias (less than 0.1 K) over a wide range of aerosol amount (11-?m optical thickness from 0.0 to 0.022). For TPW retrieval, in contrast, the biases associated with stratospheric aerosol are less satisfactory (2 kg m?2 or greater across a range of 11-?m optical thickness of 0.0?0.01). However, the authors show how to find optimal aerosol-dependent retrieval coefficients for any stratospheric aerosol distribution from knowledge of the mean and variance of that aerosol distribution. Examples of SST and TPW retrieval using simulated ATSR brightness temperature data are given.