This work is a contribution to CSIC PTI Teledetect.-- VII Encuentro de Oceanografía Física (EOF) - Expanding Ocean Frontiers Conference, VIII International Symposium on Marine Sciences, 6-8 July 2022, Las Palmas de Gran Canaria, España, In the framework of the European Space Agency (ESA) World Ocean Circulation project (WOC), the enhanced ocean wind forcing product (ERA*) has been developed to address the growing demand for accurate forcing from the ocean modelling community. The ERA* is a corrected reanalysis product that optimally combines the capacities of scatterometer observations and model reanalysis stress equivalent wind (U10S) output, by means of a geolocated scatterometer-based correction (SC) applied to the European Centre forMediumrange Weather Forecasts (ECMWF) Fifth reanalysis U10S output (ERA5). The SC consists of accumulated ERA5-scatterometer U10S component (zonal and meridional) differences over time windows of typically a few days to a month, at each ocean grid point (Trindade et al. (2020)). ERA* is able to introduce true smaller scale signal into ERA5 that corresponds to the physical processes absent or misrepresented by the latter, e.g., strong current effects (such as WBCs, highly stationary), wind effects associated with the ocean mesoscales (SST), coastal effects (land see breezes, katabatic winds), parameterization errors, and large-scale circulation effects, e.g., at the ITCZ. This is verified by comparing both products against independent scatterometer observations (e.g., HSCAT on HY-2A and HY-2B) and buoys winds.
The ERA* product is generated for the period 2010-2020. An optimized configuration of ERA* in terms of the varying scatterometer constellation over the period of interest is sought. In particular, the optimal SC time window size will depend on the scatterometer sampling, i.e., the larger the number of scatterometers in orbit is, the smaller is the time window required. The ERA* reduces the vector root-mean-square difference by 10% (5%) against independent scatterometers (buoys), with respect to that of ERA5. The new ERA* product, which thus significantly outperforms ERA5, will be freely available from theWOC webpage (https://www.worldoceancirculation.org/), This work was supported in part by the ESA study entitled "World Ocean Circulation" (4000130730/20/I-NB) and in part by the Spanish R&D projects LBAND (ESP2017-89463-C3-1-R), which is funded by MCIN/AEI/10.13039/501100011033 and "ERDF A way of making Europe", and INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also acknowledge funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2019-000928-S), Peer reviewed

Oceans form Space V Symposium, 24-28 october 2022, Venice, Italy.-- 2 pages, 2 figures, Accurate high and extreme sea surface wind observations are essential for meteorological, ocean, and climate applications. A method to inter-calibrate spaceborne scatterometer and radiometer derived high and extreme winds using NOAA hurricane “hunter” data is presented. The proposed method is effective, providing highly consistent satellite-derived extreme wind datasets in the period 2009-2020. Further work is needed though to consolidate an in-situ reference for extreme wind calibration purposes, This work was supported in part by the MCIN/AEI/10.13039/501100011033 through the Project INTERACT under Grant PID2020-114623RB-C31, and in part by the European Space Agency (ESA) through the OCEAN+EXTREMES Marine Atmosphere eXtreme Satellite Synergy (MAXSS) Project under Contract 4000132954/20/I-NB, Peer reviewed

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 for the understanding of the salinity dynamics. Scientific applications identified from the interaction with users working in the Baltic Sea will also be presented, This work has been carried out as part of the Baltic+ Salinity Dynamics project (4000126102/18/I-BG), funded by the European Space Agency. It has been also supported in part by the Spanish R&D project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

Living Planet Symposium, 23-27 May 2022, Bonn, Germany, The amount of data that must be processed in satellite missions is increasing over time, directly affecting the hardware resources and time required to carry out this processing. With more than 11 years in orbit, the SMOS mission has a lot of over-sampled data, which implies a more intensive use of the CPU and greater use of disk space if the processing is done without any type of data management. For this reason, it is increasingly necessary to optimize the resources involved in the processing of large volumes of data. Such optimizations include minimizing the processing time, achieving maximum efficiency of computational resources, and doing a good management of the generated data, both to make it more accessible and to optimize the disk space it demands.
This work presents different techniques that can be applied when designing software architectures for the particular case of the SMOS Sea Surface Salinity data processing. A study is made on how the data can be aggregated and ordered in the first stages of processing to reduce the processing time of the following stages and the disk usage of intermediate products.
The SMOS measurements can be easily divided into smaller independent processing units (such as a half-orbit or a snapshot, which is even smaller and still independent of the other snapshots). The granularity of the data allows the processing to be divided into very small pieces that can be executed in parallel, making an optimal use of CPU resources and reducing the total processing time. Disk operations, such as reading and writing files are also a big part of the processing time. Data has been arranged in a way in which disk operations are minimized (avoiding multiple reads of the same file) .
Preliminary results show an improvement of the 20% of computational time and a reduction of the 40% of the required disk space with respect to the current implementation of the Barcelona Expert Center internal data processing chain, This work has been carried out as part of the SO-FRESH project (AO/1-10461/20/I-NB)
and by means of the contract SMOS ESL L2OS both funded by the European Space Agency. It has also been
supported in part by the Spanish R&D project INTERACT (PID2020-114623RB-C31), which is funded by
MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the
“Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

23rd International Group for High Resolution Sea Surface Temperature (GHRSST) Science Team Meeting, 27 June -1 July 2022, Barcelona.-- This work is a contribution to the CSIC Thematic Interdisciplinary Platform Teledetect, Sea Surface Temperature (SST) plays an important role in the production of satellite based Sea Surface Salinity (SSS) observations. On the one hand, it is used as an auxiliary parameter for SSS retrieval from brightness temperature to produce L2 and L3 datasets. On the other hand, it is used as a template to increase spatial resolution using multifractal fusion techniques (L4 product). Traditionally, Soil Moisture and Ocean Salinity (SMOS) SSS datasets produced at the Barcelona Expert Center were based on OSTIA SST product. In this work, we revisit this election and assess different sources of satellite-derived SST products. The assessment will consist of:
- comparison with in-situ data (ARGO floats);
- performing a correlated triple collocation analysis [González- Gambau et al., 2020] between the different products to decide which one presents the lower uncertainty;
- spectral and singularity analysis to assess the spatial resolution of each SST product [Hoareau et al. 2018]., This work has been carried out as part of the SO-FRESH project (AO/1-10461/20/I-NB), funded by the European Space Agency. It has been also supported in part by the Spanish R&D project INTERACT
(PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation
(CEX2019-000928-S), Peer reviewed

23rd International Group for High Resolution Sea Surface Temperature (GHRSST) Science Team Meeting, 27 June -1 July 2022, Barcelona.-- This work is a contribution to the CSIC Thematic Interdisciplinary Platform Teledetect.-- This work has been carried out as part of the Universitat Autònoma de Barcelona Mathematics bachelor’s thesis of Lluïsa Puig-Moner, Exponents in remote sensed images of the ocean. Horizontal transport and mixing processes are key to properly understand changes in the global ocean. Finite Size Lyapunov Exponents characterise the rate of separation of infinitesimally close trajectories and therefore provide information of the dispersion processes and the Lagrangian Coherent Structures (i.e. transport barriers and fronts). In order to estimate the Finite Size Lyapunov Exponents (and also Finite Time Lyapunov Exponents), a sequence long enough of the velocity field is required. The Singularity Exponents are a dimensionless measure of the degree of regularity or irregularity of a function at each point of its domain. The estimation of the Singularity Exponents is related to the multifractal properties of any ocean scalar satellite image and then no velocity field is required. Numerical estimations of Singularity Exponents show evidence that different ocean scalars present the same Singularity Exponents and that they coincide with the streamlines of the fow. This in particular means that we can estimate the streamlines from the Singularity Exponents derived from Sea Surface Temperature maps. Here we explore the possibility of computing the Finite Size Lyapunov Exponents without the need of any velocity field. For this we numerically analyse one year of satellite ocean images of Absolute Dynamic Topography and Sea Surface Temperature. Numerical estimations show a linear relationship between the Singularity Exponents and the Finite Size Lyapunov Exponents which is more robust in the case of the Singularity Exponent from Sea Surface Temperature than in the case of the Absolute Dynamic Topography. In the talk, we plan to discuss the causes of these differences and the steps forward to address this equivalence from a theoretical point of view, It has been also supported in part by the Spanish R&D project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

23rd International Group for High Resolution Sea Surface Temperature (GHRSST) Science Team Meeting, 27 June -1 July 2022, Barcelona.-- This work is a contribution to the CSIC Thematic Interdisciplinary Platform Teledetect, In the context of the ESA Baltic+ Salinity Dynamics project, the first SMOS (Soil Moisture and Ocean Salinity) sea surface salinity (SSS) dedicated products over the Baltic Sea have been developed. A first prototype of these SSS products evidenced the sea surface temperature (SST) as one important driver of the SSS errors. Considering the low sensitivity of brightness temperatures to SSS changes in cold waters (with a mean value below 3 degrees C in winter in the Baltic Sea), it is crucial to use the most accurate SST product for the salinity retrieval. Besides, SST is used as a template when using multifractal fusion techniques to increase the spatial resolution of these SSS products.
In order to identify the most suitable SST product over the Baltic Sea, we have analysed the state-ofthe- art EO-based SST products (OSTIA, CMC, REMSS, CCI) [Woo and Park, 2020], by comparing them with the collocated in-situ temperature measurements provided by SeaDataNet. This analysis has revealed that the best quality salinity product over the Baltic Sea is the CCI SST, with a standard deviation of the difference with in-situ of 0.62 degrees C, , which is still large compared to open ocean regions. Therefore, EO SSS products would benefit from improvements in SST products over the Baltic Sea, This work has been carried out as part of the Baltic+ Salinity Dynamics project (4000126102/18/I-BG), funded
by the European Space Agency. It has been also supported in part by the Spanish R&D project INTERACT
(PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding
from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation
(CEX2019-000928-S), Peer reviewed

Ocean Salinity Conference, 6-9 June 2022, New York, USA, This work has been carried out as part of the Baltic+ Salinity Dynamics project (4000126102/18/I-BG), funded by the European Space Agency. It has been also supported in part by the Spanish R&D project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

Ocean Salinity Conference, 6-9 June 2022, New York, USA, This work has been carried out as part of the SO-FRESH project (AO/1-10461/20/I-NB) and by means of the contract SMOS ESL L2OS both funded by the European Space Agency. It has also been supported in part by the Spanish R&D project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

This work is a contribution to the CSIC Thematic Interdisciplinary Platform Teledetect.-- Ocean Salinity Conference, 6-9 June 2022, New York, USA, This work has been carried out as part of the regional initiative An Earth Observation Data for Science and Innovation in the Black Sea project funded by the European Space Agency. It has been also supported in part by the Spanish R&D project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033. We also received funding from the Spanish government through the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S), Peer reviewed

The ERA* stress-equivalent wind (UI0S) is a correction of the ECMWF Fifth Reanalysis (ERA5) output by means of geo-Iocated scatterometer-ERA5 differences over a 3-day temporal window, in which the combined sampling of the Advanced Scatterometers on board the Metop satellite series (ASCAT-A, -B, and -C) and the SCATSat-l scatterometer (OSCAT2) have been used, for the year 2019. ERA * can correct for local, persistent NWP model output errors associated with physical processes that are absent or misrepresented by the model, e.g., strong current effects (such as western boundary current systems, highly stationary), wind effects associated with the ocean mesoscales (sea surface temperature), coastal effects (land see breezes, katabatic winds), Planetary Boundary Layer parameterization errors, and large-scale circulation effects, e.g., at the inter-tropical convergence zone., This work was supported in part by the Spanish R&D project LBAND (ESP2017-89463-C3-1-R), which is funded by MCIN/AEI/10.13039/501100011033 and “ERDF A way of making Europe”, and project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033., Peer Reviewed

The ERA* stress-equivalent wind (UI0S) is a correction of the ECMWF Fifth Reanalysis (ERA5) output by means of geo-Iocated scatterometer-ERA5 differences over a 3-day temporal window, in which the combined sampling of the Advanced Scatterometers on board the Metop satellite series (ASCAT-A, -B, and -C) and the SCATSat-l scatterometer (OSCAT2) have been used, for the year 2019. ERA * can correct for local, persistent NWP model output errors associated with physical processes that are absent or misrepresented by the model, e.g., strong current effects (such as western boundary current systems, highly stationary), wind effects associated with the ocean mesoscales (sea surface temperature), coastal effects (land see breezes, katabatic winds), Planetary Boundary Layer parameterization errors, and large-scale circulation effects, e.g., at the inter-tropical convergence zone., This work was supported in part by the Spanish R&D project LBAND (ESP2017-89463-C3-1-R), which is funded by MCIN/AEI/10.13039/501100011033 and “ERDF A way of making Europe”, and project INTERACT (PID2020-114623RB-C31), which is funded by MCIN/AEI/10.13039/501100011033., Peer Reviewed, Postprint (published version)