| BALTIC+ Geodetic SAR for Baltic Height System Unification (SAR-HSU) ||Height systems and related sea level observations are based on a number of measurement systems, which all have their own characteristics and deliver different type of observations. Traditionally, sea level is observed at tide gauge stations, [...]||TECHNICAL UNIVERSITY OF MUNICH (DE)||Science||Baltic, GOCE, SAR, science||Height systems and related sea level observations are based on a number of measurement systems, which all have their own characteristics and deliver different type of observations. Traditionally, sea level is observed at tide gauge stations, which usually also serve as height reference stations for national levelling networks and therefore define a height system of a country. Thus sea level research across countries is closely linked to height system unification and needs to be regarded jointly. In order to analyse all observations they need to be available in a common reference frame. Within this project three major objectives are addressed. Connection of tide gauge markers with the GNSS network geometrically by the geodetic SAR technique in order to determine the relative vertical motion and to correct the tide gauge readings.
Determine a GOCE based high resolution geoid at tide gauge stations in order to deliver absolute heights of tide gauges with respect to a global equipotential surface as reference.
Joint analysis of geometrical and physical reference frames to make them compatible, and to determine corrections to be applied for combined analysis of geometric and physical heights. These objectives are addressed by the project team with complementary expertise. The Baltic Sea serves as test area with very good geodetic infrastructure in order to identify the capabilities of the geodetic SAR technique for height system unification and determination of the absolute sea level at tide gauges.|
| BALTIC+ Salinity Dynamics ||This project aims to study the potential benefit of incorporating satellite-derived Sea Surface Salinity (SSS) measurements into oceanographic and environmental applications within the Baltic Sea. For such purpose, a team led by ARGANS Ltd (UK) [...]||ARGANS FRANCE (FR)||Science||Baltic, ocean science cluster, science||This project aims to study the potential benefit of incorporating satellite-derived Sea Surface Salinity (SSS) measurements into oceanographic and environmental applications within the Baltic Sea. For such purpose, a team led by ARGANS Ltd (UK) with participation of Barcelona Expert Centre (BEC / ICM-CSIC, Spain) and the Finnish Meteorological Institute (FMI, Finland) will develop an innovative SSS product from the measurements obtained by the Earth Explorer SMOS. It incorporates advanced techniques for noise and bias correction to deal with the specific difficulties that the retrieval of salinity has in the region: land/sea contamination, sea/ice contamination, manmade radio-frequency interferences, and limitations in the current dielectric constant. The project will generate data by modifying substantially the existing production chain from L0 data to L4 maps, aiming to obtain meaningful information for applications. The characteristics of the final products will be enhanced both spatially and temporally thanks to data fusion, in order to meet the end-user requirements. SSS accuracy will be also improved to meet the needs of the scientific community operating in this basin. In the first half of the project, the focus will be in improving the brightness temperatures and adequate the image reconstruction process specifically for the Baltic Sea. In the second half of the project, the emphasis will be in the removal of remaining biases and generation of the fused L4 products, as well as assessing the performance and impact it has in the various case studies. Specific attention will be drawn to investigate the added-value of this new product to address the scientific challenges associated to salinity, as identified by Baltic Earth community: salinity annual trends and budgets; insights of the coupling mechanisms involved in the interfaces atmosphere-ice-sea; climatological projections. In addition, it is expected to estimate how other types of studies would benefit of incorporating SSS, like regional biochemical models, or any other in which frontal areas identification could be of relevance. For instance, river run-offs, sea ice formation/melting and, marginally, North Sea water intrusions. The project benefits of the existence of a long time series of observations provided by SMOS, which allows the team to explore longer time scales. The expected higher time and spatial coverage will be key factors in the outcome of this project, in a region in which in situ observations of salinity are scarce or concentrated in the coastal areas. It is expected that the results of this activity will lead towards an increase in the presence of SSS data.|
| BALTIC+ Sea-Land biogeochemical linkages (SeaLaBio) ||The overall goal of the ESA funded project Baltic+ SeaLaBio (Sea-Land Biogeochemical linkages) running from Dec 2018 to May 2020 is to develop methods for assessing carbon dynamics and eutrophication in the Baltic Sea through integrated use of [...]||FINNISH ENVIRONMENT INSTITUTE (SYKE) (FI)||Science||Baltic, carbon cycle, carbon science cluster, land, ocean science cluster, oceans, Sentinel-2, Sentinel-3||The overall goal of the ESA funded project Baltic+ SeaLaBio (Sea-Land Biogeochemical linkages) running from Dec 2018 to May 2020 is to develop methods for assessing carbon dynamics and eutrophication in the Baltic Sea through integrated use of EO, models, and ground-based data
The poor state of the Baltic Sea again became apparent during summer 2018 in form of massive and long-lasting cyanobacteria blooms. Warm and sunny weather, combined with good availability of nutrients led to the worst algae situation in a decade. Climate change is expected to cause further warming in this region making these events more and more common in the future.
The decades of dumping untreated waste water into the Baltic Sea and the use of fertilizers in agriculture have resulted in strong internal loading. While the water treatment situation has improved and fertilizers are being used more responsibly, the flux of carbon and nutrients from land to sea is still great and in many areas largely unknown. The Sentinel satellites of the Copernicus programme offer an excellent opportunity for characterizing and monitoring the fluxes and processes occurring in coastal zones. This in turn will lead to improved process understanding.
With this in mind, the Baltic+ SeaLaBio research project aims to find an answer to the question:
• Can we quantify the carbon flux from land to sea with Sentinel-3 (S3) OLCI and Sentinel-2 (S2) MSI data in the Baltic Sea region? And if not, what are the main obstacles and potential solutions to be addressed in the future?
In addition to frequent cyanobacteria blooms, the high absorption by colored dissolved organic matter (CDOM) causes problems to the utilization of EO for monitoring the state of the Baltic Sea. The available processors for S3 and S2 often provide overestimated values for Chlorophyll a and underestimate CDOM. The main source of these problems is the failure of the atmospheric correction to provide reasonable marine reflectances. Thus, the project focuses especially on improving the atmospheric correction and in-water inversion algorithms for S3 and S2 images. The developed methods will be validated with in situ data collected from different parts of the Baltic Sea. We will also improve the spatial resolution of a biogeochemical (BGC) model (Ecological ReGional Ocean Model, ERGOM) and compare its output against the EO results.
S3 OLCI has a better band combination for water quality estimation than S2 but its spatial resolution limits its use in river estuaries and archipelagos common in the coastal areas of the Baltic Sea. Hence, the synergistic use of these two data sources can lead to improved coverage in coastal regions without compromising the thematic quality of the data.
The project will actively disseminate its progress and results in various Baltic Sea and EO events.|
| BALTIC+ SEAL – Sea Level ||The current knowledge of the water circulation in the Baltic Sea comes essentially from in situ observations and models. The Baltic+ SEAL (Sea Level) Project aims at providing a consistent description of the sea level variability in the Baltic [...]||TECHNICAL UNIVERSITY OF MUNICH (DE)||Science||altimeter, applications, Baltic, marine environment, ocean science cluster, science||The current knowledge of the water circulation in the Baltic Sea comes essentially from in situ observations and models. The Baltic+ SEAL (Sea Level) Project aims at providing a consistent description of the sea level variability in the Baltic Sea area in terms of seasonal and inter-annual variation and put the results in relationship with the forcing associated with this variability, using a developed dedicated coastal altimetry product. The objective is to create and validate a novel multi-mission sea level product in order to improve the performances of the current state-of-the-art of the ESA efforts in this topic: the Sea Level Climate Change Initiative (SL_cci). In this sense, this project can actually be considered as a laboratory in which advanced solutions in the pre-processing and post-processing of satellite altimetry can be tested before being transferred to global initiatives, such as the future phases of SL_cci.
The Baltic Sea includes the two main areas in which the use of satellite altimetry has been severely limited since the start of the “altimetry era”: the presence of sea ice and the proximity of the coast. During the winter season and the sea ice maximum in end of February, 40% of the Baltic Sea is covered by sea ice. The Team aims to apply an unsupervised classification approach to all possible altimetry satellite missions treated in this project (TOPEX-Poseidon, ERS-1/2, Envisat, Jason-1/2/3, SARAL/AltiKa, CryoSat-2, Sentinel-3A/B) to get reliable open water observations and adapt the classification approach to the sea-ice/open-water conditions and different satellite altimetry mission characteristics (e.g. pulse-limited, SAR).
The Baltic Sea area is also strongly impacted by Vertical Land Motion and in particular by the glacial isostatic adjustment. As it has the advantage of being an area very well sampled by tide gauges, which measure relative sea level, the Project aims at constituting a more reliable source to compare the absolute sea level from altimetry with the absolute sea level obtained by subtracting the Vertical Land Motion from the trends at the tide gauge and could even be the data source for experiments of differentiation between TG and altimetry trends in the absence of GPS measurements.|