Six Joined Research activity Projects (JRAPS have been achieved within JERICO-NEXT. These projects have been set up to tackle some of the complex technical and scientifical issues associated with the implementation of Coastal Ocean Observing over a wide range of environmental conditions and spatiotemporal scales. The topics of these projects have been defined in relation with some of the Marine Strategy Framework Directive:

JRAP 1: Biodiversity of plankton, harmful algal blooms and eutrophication,

JRAP 2: Monitoring changes in microbenthic biodiversity, assessing potential environmental controls and functional consequences

JRAP 3: Occurrence of contaminants in Northern coastal waters and biological responses

JRAP 4: 4D characterization of trans-boundary hydrography and transport

JRAP 5: Coastal carbon fluxes and biogeochemical cycling

JRAP 6: Operational oceanography and forecasting

In its first part, this document reports the work led in the framework of the JRAP activities during the whole JERICO-NEXT project. Itn its second part, it also shows how the experience gained from JRAP activities contributed to the elaboration of the JERICO-RI science strategy, which is presented in JERICO-NEXT D1.2.

JRAP 1 explored different automated or semi-automated innovative approaches for improving the temporal and spatial resolution of phytoplankton observations based on different plarforms: research cruises, fixed platforms, moorings and/or ships of opportunity. Based on seven different research actions, it clearly showed how the combination of these techniques allowed to reach new insights into the functional diversity and photosynthetic status of phytoplankton communities in different environmental and hydrological conditions (i.e., from oligotrophic and mesotrophic to eutrophic conditions, and from brackish to saline systems). JRAP 1 nevertheless also identified gaps and underlined the necessity in continuing technological developments to improve the resolution and understanding of phytoplankton dynamics, in connection with the requirements of environmental managing at a regional, national and international level.

JRAP 2 tackled three main questions: (1) Do alternative techniques provide sound surrogates for the classical analysis of benthic macrofauna composition? (2) Irrespective of the nature of the disturbance, does the relationship between disturbance intensity and benthic diversity follow the same pattern? and (3) What are the functional consequences of a benthic macrofauna diversity loss on ecosystem functioning? JRAP 2 supported the ability of surface and sediment profile imaging and 16S rRNA metabarcoding of benthic microfauna in detecting the impact of disturbance gradients on benhic diversity. JRAP 2 also showed that the effects of disturbance on benthic diversity are not necessarily gradual and may result from non a priori identified disturbance sources. The functional consequences of biodiversity loss were assessed in only one of the four actions achieved by JRAP 2. Results showed no clear effect of benthic macrofauna species richness on sedimented organic matter remineralization.

JRAP 3 tackled four main questions: (1) Can existing integrative sampling methods (i.e. passive samplers) be effectively used in combination with existing CRI to obtain reliable data on marine chemical pollution? (2) Can CRI be used to support exploratory monitoring of marine pollution to identify new chemical contaminants? (3) Can the drivers of spatial distribution of chemical contaminants in coastal waters be assessed using data from infrastructure sensors and spatial analyses? and (4) Is there a co-variance between contaminant signals and biological responses? JRAP 3 results suggested that passive samplers were able to report expected gradients of variability in measured concentrations and could now be routinely used to address monitoring of chemical pollution in coastal areas. They also confirmed the benefit of using FerryBox based sampling to carry out monitoring of contaminants in coastal water. JRAP 3 reported no simple overall correlation between the levels of detected chemicals and the distance of the sampling sites to the coast. JRAP 3, however, developed a specific spatial analysis allowing for correlating an index of anthropic impact with measured contaminant concentrations. JRAP 3 results at last showed the concordance between selected microbial molecular markers of hydrocarbon pollution and the sum of 29 Persistant Aromatic Hydrocarbons, which highlighted the possibility of using chemical and molecular biomarkers to retrieve information of pollution influence on microbial community assemblages.

JRAP 4 tackled three main questions: (1) Can we use JERICO infrastructures to study the 4D shelf/slope circulation and transports and their time variability? (2) What is the impact of the ocean transport on the distribution of floating and dissolved matter? and (3) How can we maximize the impact of the JERICO-RI for the assessment of coastal transport? JRAP 4 showed the benefit of new high-resolution observations through new deployments (including HF radars and innovating moorings) for the upgrading of current coastal observatories. It successfully tested several HF radar data advanced processing and analysing procedures. JRAP 4 successfully performed several ad-hoc experiments to quantify the impact of ocean transport on the distribution of biological quantities and pollution. JRAP 4 finally underlined the interest of Observing System Simulation Experiments to optimize existing coastal ocean observing network and to better design future observatories.

JRAP 5 tackled three main questions: (1) What kind of role European Coastal Ocean and Marginal Seas have on the marine carbon system? (2) What is the role of biological activity on marine carbon uptake or release? and (3) How should the integrated C-cycle monitoring be organized in coastal regions? JRAP 5 showed the high regional variability and regional differences in pCO2 dynamics between areas, which could either constiture a carbon sinks or sources. Based on a limited number of stations and VOS routes, JRAP 5 concluded that biological activity had a significant role on the marine carbon balance. At last, JRAP 5 stressed the need for better coordination between coastal carbonate system observations, with frequent instrument comparisons.

JRAP 6 tackled four main questions through the implementation of coastal model assessment studies and observing system experiments in different areas of European coastal waters: (1) How accurate are our ocean models in coastal areas? (2) How could we improve these models? (3) What is the impact of coastal observations on the model performance after data assimilation? and (4) What would be the impact of potentially future additional observations? Overall, models were found to be able to properly reproduce the spatio-temporal scales of sea surface current variability. However, JRAP 6 also identified gaps in the performances of current hydrodynamical models. JRAP 6 evaluated the sensitivity of model results to the horizontal resolution, model parameters, surface forcing or to the treatment of open boundary conditions, providing solutions to improve them. Observing System Experiments allowed evaluating the positive impact of the assimilation of glider, FerryBox, fixed moorings and HF radar observations on model performances. Observing System Simulation Experiments were also performed to evaluate the impact of future observing systems. Overall, and considering the specificities of coastal situations in European waters, Overall, JRAP6 was able to demonstrate the usefulness of JERICO-NEXT coastal observations in distinct environments, leading to an improvement of the understanding and of the performance of high-resolution numerical models implemented in the coastal European ocean.

Through the gains of experience generated within its six JRAPs, WP4 contributed to the five pillars of the JERICO-RI scientific strategy, namely:

Pillar 1: Developping innovative technologies for Coastal Ocean Observing and modelling

Pillar 2: Enhancing integrated Coastal Ocean Monitoring

Pillar 3: Interfacing with other ocean observing initiatives operating at different spatiotemporal scales

Pillar 4: Fostering societal impact for a larger community of stakeholders

Pillar 5: Establishing observing objectives, strategy and implementation at the regional level

Pillar 1: All JRAPs clearly confirmed that the development of innovative technologies constitutes a major key point for the future of Coastal Ocean Observing. They more specifically showed that Technology Readiness Levels differ between disciplines and recommended to carry out specific developments for better balancing the disciplinary scope of (semi)automated observations. JRAPs also underlined the necessity of developing multidisciplinary platforms to enhance the emergence of holistic observation. They stressed the importance of modelling in addressing the spatial heterogeneity and temporal dynamics of physical processes taking place in the Coastal Ocean and the strong interest in putting a focus on the development of biological/biogeochemical models and on their coupling with physical models.

Pillar 2: JRAPs identified the harmonization of observations as a key issue for Coastal Ocean Observing. They however also acknowledged limitations and plead for for the definition of an optimal threshold between homogenization and the consideration of regional specificities while designing a future European Coastal Ocean Observing infrastructure. They more specifically pinpointed that such a threshold is likely to differ according to the nature of tackled environmental issues. The implementation of multidisciplinarity within the different JRAPs was overall considered as unsatisfactory. Two ways forward were identified: (1) developing new multidisciplinary platforms allowing for high frequency data acquisition, and (2) a priori optimizing monitoring strategies. It was also stressed that a threshold should be reached between an a priori optimization (which is necessary based on current knowledge) and a certain degree of ability to detect the impact of non-foreseen changes/processes when designing future monitoring strategies.

Pillar 3: All JRAPs involved tight interactions with other observing initiatives consisting in observing infrastructures and/or research projects. The interactions with other observing initiatives proved satisfactory. They were, nevertheless, facilitated by the small spatiotemporal scales addressed by most JRAPs and it is anticipated that future interactions operating at larger scales would benefit a strong coordination of monitoring strategies. The interactions with research projects sometimes proved odd and should be defined over a long-term perspective as well.

Pillar 4: Addressed topics clearly varied both within and between JRAPs. This heterogeneity refers both to the nature (i.e., fundamental vs applied) and the spatial scale (i.e., from the local to the pan-european level) of addressed issues. Overall, it was stressed that such a diversity should clearly be taken in consideration while designing a future pan-European Coastal Ocean Observing infrastructure and suggested that stakeholders should be deeper involved in the definition of the products derived from Coastal Ocean Observing so that they become better suited in tackling their concerns.

Pillar 5: Most JRAPs were implemented at a sub regional spatial scale and their designs mostly consisted of complementary actions achieved at different sites representative of a large set of environmental conditions and issues. This structuration showed clear limitation relative to the implementation of the first four pillars of the JERICO-RI strategies. It was therefore suggested that the systems and tools developed within JERICO-NEXT could become part of regional systems and most JRAPs therefore recommanded the design and implementation of a future Coastal Ocean Observing insfrastructure as a network of Augmented Regional Coastal Observatories.