The first image from the European Space Agency (ESA) Sentinel-3A Sea and Land Surface Temperature Radiometer (SLSTR) depicts thermal signatures over a part of western Namibia and the South Atlantic Ocean. The Namibian land surface is shown in red-orange colors, corresponding to a temperature range of 301-319K. The blue colors over the ocean correspond to a temperature range of 285-295K. Black areas correspond to clouds, which are opaque to thermal-infrared radiation.
Cold water is seen along the Namibian coast upwelling from deeper waters. The Benguela current flows north along the west coast of South Africa driven by southeasterly winds creating coastal upwelling. Understanding changes in the pattern of these waters is important for fisheries, for example.
“With dual-view measurement capability, it will be used to derive accurate surface temperature, a key parameter at the ocean-atmosphere boundary,” noted Hilary Wilson, EUMETSAT’s Sentinel-3 project manager. “Therefore, it is important for operational oceanography and meteorology, and ultimately for long-term climate monitoring.”
This image published on April 5, 2016, the first using Sentinel-3A’s SLSTR thermal-infrared imager, shows the “brightness temperature” that corresponds to radiation emitted from the surface. (Credit: Contains modified Copernicus Sentinel data )