Oceanographic added-value of the first regional SMOS sea surface salinity products over the Baltic Sea

• Main Authors: González Gambau, Verónica, Olmedo, Estrella, González-Haro, Cristina, Turiel, Antonio, García Espriu, Aina, Gabarró, Carolina, Tuomi, Laura, Catany, Rafael, Arias, Manuel, Sabia, Roberto, Fernández-Prieto, Diego
• Other Authors: European Space Agency, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España)
• Format: Conference Object
• Language: English
• Published: European Space Agency
• Subjects: The Narrows; North Atlantic
• Online Access: http://hdl.handle.net/10261/331975; https://doi.org/10.13039/501100011033; https://doi.org/10.13039/501100000844

Living Planet Symposium, 23-27 May 2022, Bonn, Germany The Baltic Sea is a strongly stratified semi-enclosed sea with a large freshwater supply from rivers, net precipitation and high-saline water exchange from the North Sea. In the Danish Straits the water exchange is hampered by bathymetric and hydrodynamic restrictions. The shallow depth yields to highly variable ocean dynamics. The water exchange with the North Atlantic Ocean is restricted by the narrows and sills of the Danish Straits and river outflows. The bottom water in the deep sub-basins is ventilated by major Baltic saltwater inflows. These complex oceanographic conditions are not well described in current model simulations. Moreover, the available in situ data in the region is temporally and spatially very sparse. Earth Observation salinity measurements have a great potential to help in the understanding of the dynamics in the Baltic Sea. However, this basin is one of the most challenging regions for the satellite sea surface salinity (SSS) retrieval. The available EO-based global SSS products are quite limited in terms of spatio-temporal coverage and quality. This is mainly due to technical limitations that strongly affect the brightness temperatures (TB), such as the high contamination by interferences and the contamination close to land and ice edges. Moreover, the sensitivity of TB to SSS changes is very low in cold waters and dielectric models present limitations in this low salinity regime. In the ESA Baltic+ Salinity Dynamics project, new regional SSS products derived from the European Soil Moisture and Ocean Salinity (SMOS) measurements were developed. In this work, we describe the enhanced algorithms used in the generation of SMOS SSS fields. A complete quality assessment with respect to in situ measurements is also presented. Finally, we compare the satellite SSS measurements with a Baltic reanalysis and in situ measurements time series, focusing on the SSS dynamics captured by Baltic+ SSS products and the added-value that can provide ...