Sea surface temperature data

Figure 1: AVHRR 7-day SST composite 22-28 April 2007.

Sea surface temperature (SST) data are used to observe physical phenomena such as currents, fronts, and eddies, and SST is an important factor controlling biological activity or influencing animal behaviour. SST data are produced by NEODAAS from the AVHRR series at ~1 km resolution (at nadir). Approximately 14 AVHRR passes are received at Dundee per day and provide typically 4-6 views of any location over the UK and surrounding coastal/oceanic waters. NEODAAS can provide consistent products from the near 30 years long AVHRR archive. The processing involves calibration, SST calculation and geo-correction within pre-defined regions of interest. Weekly composites comprising all the cloud free portions over 7 days are also produced (e.g. Fig. 1). Finally, individual images and composites are placed on the web site. SST is produced for regions outside the Dundee range, for cruises or observatories worldwide, via automatic data downloads from NOAA. SST is also produced from MODIS and on request can be obtained from ESA’s AATSR. In high cloud situations, such as the Arabian Sea monsoon, cloud-penetrating microwave SST products from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) and Tropical Rainfall Mapping Mission Microwave Imager (TMI) can be provided, courtesy of Remote Sensing Systems Inc, at low-resolution data (25-km). NEODAAS maintains an archive of global 4 km or 9 km temporal composites from NASA including AVHRR-Pathfinder and MODIS. Composites are useful to construct time series at medium resolution or over synoptic scales. NEODAAS have started a collaboration with the UK Met Office/GODAE High-resolution SST-Pilot Project (GHRSST-PP) to provide the entire NEODAAS AVHRR archive in L2P format for ingestion into the GHRSST product. In the future NEODAAS will use the MetOp AVHRR and follow-on instruments on the NASA/NOAA National Polar-orbiting Operational Environmental Satellite System (NPOESS) and NPOESS Preparatory Project (NPP) and ESA Sentinel-3.