SMOS SMAP High Resolution SSS maps in regions of high variability, generated by CATDS CEC
Résumé
Users of satellite Sea Surface Salinity products stress the importance of temporal and spatial resolution for the study of processes especially in river plumes. The Ocean Salinity Center of Expertise for CATDS (CATDS CEC-OS) has derived a new methodology aiming at keeping high temporal SMOS and SMAP SSS variability in highly variable regions while filtering outliers in low variability regions. As for the global 18-day CATDS CEC products, the high resolution (HR) products are built using a temporal interpolation, grid node per grid node. This interpolation is done simultaneously with the estimation of the across-track SSS biases [Boutin et al., 2018]. The main change with respect to the global CEC CATDS products comes from the different kernel used for the temporal smoothing. The use of an exponential kernel for the temporal smoothing allows: - an improvement of the spatial contrasts either on the SMOS period alone or on the SMOS + SMAP period on almost all considered regional areas. - a better restitution of the temporal dynamics for the low SSS at the mouths of the river plumes There is a substantial gain in the correlation indicators with the In Situ data in the SMOS+SMAP period with an exponential core. Overall, there is no noise degradation with the HR products. Moreover, there is a suppression of certain orbit "lineages" with the use of an exponential kernel. This version 0 of the products are delivered in 8 regions. Feedbacks from users about the quality of these new experimental products are very welcome and essential for the CATDS expertise center to improve future versions. A detailed description is described on https://data.catds.fr/cecos-locean/Ocean_products/HIGH_RESOLUTION_8_REGIONS/documentation/Doc_High_Resolution_8_Regions.pdf.