An Evaluation of a Self-Calibrating Infrared Radiometer for Measuring Sea Surface Temperature

Abstract

Abstract Satellite radiometer measurements of global sea surface temperature (SST) with an accuracy of 0.3 K are required for climate change monitoring. In order to validate that this accuracy can be achieved, in situ measurements of sea surface radiance must be made during satellite overpasses. In the past decade attempts have been made to design self-calibrating, infrared radiometers for measuring SST from research ships, and some commercially manufactured models are now available. The British Antarctic Survey deployed one such radiometer on board the royal research ship Bransfield between October 1991 and May 1992. Its purpose was to measure SST within the Along Track Scanning Radiometer (ATSR) swath when the ERS-1 satellite passed over the ship. The ship radiometer was claimed to have an accuracy of ±0.1 K but this had not been verified under realistic measurement conditions. An evaluation of the radiometer's accuracy was therefore carried out during a voyage from the British Isles to Antarctica. At i...