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MEDiterranean Sea Acidification in a changing climate

Final Report Summary - MEDSEA (MEDiterranean Sea Acidification in a changing climate)

Executive Summary:
As carbon emissions increase and carbon dioxide levels (CO2) in the atmosphere rise, so does the concentration of CO2 in the ocean. The ocean has been very efficient in absorbing CO2 and this has decreased the accumulation of CO2 in the atmosphere and thus reduced the potential human-induced ‘warming’ feedback on our climate. However, the ocean is absorbing atmospheric CO2 in such unprecedented rate that it is rapidly changing the chemistry of the ocean resulting in ‘ocean acidification (OA)’, a reduction in pH, carbonate ion concentration, and the capacity of seawater to buffer changes in its chemistry. OA is a global environmental issue posing a threat to open ocean and coastal marine ecosystems, including the Mediterranean Sea. The impacts of OA are generally acknowledged but in complex and highly variable coastal areas and marginal seas it remains vastly understudied. The Mediterranean Sea Acidification in a changing climate (MedSeA) project ( greatly contributed to build a clearer picture of the Mediterranean Sea’s response to human-induced elevated atmospheric CO2 conditions focusing on OA and ocean warming. During the project duration (2011-2014) 60% of the total scientific articles contributing to OA understanding in the Mediterranean Sea were provided by the over 120 MedSeA scientists from 16 partner and 6 associated partner institutions from 12 countries. MedSeA assessed the chemical, climatic, ecological, biological, and economical changes of the Mediterranean Sea driven by increases in CO2 and other greenhouse gases providing projections for this century and first sets of adaptation and mitigation strategies.
Mediterranean Sea acidification can be already detected. The available data sets from the North-western Mediterranean Sea indicate that in the 18-year period 1995–2013 alone, acidity has already increased more than 10 %. Projections of CO2 emissions indicate a sustained sea uptake of anthropogenic carbon and a 30% increase in acidification between years 2010 and 2050 if we continue to emit CO2 at the same rate. This implies, since the industrial revolution and within only a few decades, acidification of the Mediterranean Sea is likely to increase by 150% at the end of the century. Since this deep semi- enclosed sea is characterized by an active exchange of waters from the surface to depth, which effectively distributes the heat, and anthropogenic carbon to the interior of the basin, the deep waters are warming and acidifying too. There is a high level of certainty that the project change in the atmosphere CO2 (550 ppm by 2050) will lead to an average surface warming from 1 to 1.5°C in the Eastern Mediterranean, Aegean and Adriatic Sea between 2000 and 2050. In summer, the average surface temperature is likely to constantly exceed 29°C in the South Eastern Mediterranean.
Iconic Mediterranean ecosystems such as Coralligenous reefs, Vermetid snail reefs and sea grass meadows are threatened by OA and/or warming. These ecosystem-building species create rich key habitats and homes to thousands of species, and also protect shores from erosion as well as offer a source of food and natural products to society. These hot-spots of Mediterranean Sea biodiversity prospered over millennia and served human populations in the region, but are now facing considerable decline. The slowly growing Mediterranean red coral (Corallium rubrum) is extremely sensitive to OA conditions. This has major implications for the Red Coral industry, which has not only economic significance but also cultural importance in the Mediterranean region. OA and warming modify the abundance and the functioning of plankton groups living in the Mediterranean, including those of shell-forming organisms like coccolithophores and pteropds. Other marine biota, like viruses and bacteria appear less sensitive.
Impacts of OA and warming may extend to several Mediterranean marine and coastal ecosystem services, including providing food, supporting recreational activities, absorbing carbon, climate regulation, and coastal protection. Coastal areas with economic activities directly depending on marine resources may face serious impacts on employment and benefits in sectors like aquaculture, open sea fisheries and tourism, which is relevant to many Mediterranean countries. Tourism may be affected by OA and warming through degradation of marine ecosystems (loss of iconic species from the coralligenous, such as gorgonians - soft coral) on diving experiences and through jellyfish outbreaks. Sensitivity of shell-forming species such as bivalve mollusks to changes in temperature and acidity represent a threat to the aquaculture sector representing a total production of about 153,000 tons in 2012 with a total value of approximately € 225 million.
Adaptation and mitigation strategies, and policies at global, regional and local scales need to be implemented as they are the only certain, effective way to reduce CO2 emissions to the atmosphere and associated ocean acidification. Mediterranean Sea acidification may be more severe in areas where human activities and impacts, such as nutrient runoff from agriculture, further increase acidity. Agricultural run-off from land and other pressures linked with human activities on Mediterranean ecosystems needs to be more strictly regulated. In addition, adaptation policies are required as an increase in atmospheric CO2 concentration seems unavoidable. The combination of mitigation and adaptation can assure that the Mediterranean can continue to sustain livelihoods, provide food and protect shorelines.

Project Context and Objectives:
As atmospheric CO2 levels continue to rise, thermodynamics and air-sea gas transfer processes drive some of the excess CO2 into the ocean surface waters, alleviating climate change. This process leads to shifts in seawater acid-base chemical speciation, lowering pH, increasing the concentration of bicarbonate ions, decreasing the concentration of carbonate ions and lowering the calcium carbonate saturation state (in other words “ocean acidification”). Ocean acidification is now widely recognize as a relevant issue for the future being of the nine planetary boundaries that can seriously endanger the future humanity posing a threat to marine ecosystems and may bringing potentially large changes in global biogeochemical cycles. In addition, this acidification may well have large socio-economic impacts ranging from those on tourism (e.g. owing to coral degradation and invasion of non-endemic species) to those on wild fisheries and aquaculture (owing to altered life cycles of key surface- and bottom-dwelling organisms, including shellfish). There is growing concern that impacts of anthropogenic acidification may propagate from individual organisms up through marine food webs, affecting commercial fisheries and shellfish industries as well as threatening protein supply and food security for millions of people. The effects on such marine-based activities could indirectly affect land-based economic activities and jobs on a much larger scale.

Although the general impact of acidification on water chemistry is globally well understood, fine-scale regional models are needed to resolve the complexity of the physical and ecological interactions of coastal and small and complex basins, such as the Mediterranean Sea. The Mediterranean Sea is considered a small-scale ocean with high environmental variability and steep physicochemical gradients within a relatively restricted region. Its circulation is characterized by zonal gradients of physicochemical variables, with salinity, temperature, stratification and alkalinity all increasing towards the east. The generally low-nutrient (from oligotrophic to ultra-oligotrophic) waters offshore stand in contrast to many near-shore regions, often containing coral and seagrass ecosystems, which are affected by human-induced eutrophication. The consequences of this process threaten the health of the Mediterranean Sea adding to other anthropogenic pressures, including those of climate change. To properly project how key biogeochemical and ecosystem processes will change, it is fundamental to adequately represent the general circulation of the Mediterranean basin, i.e. both the fine-scale processes that control it (e.g. eddies and deep convection), and the highly variable atmospheric forcing.

The Mediterranean Sea Acidification in a changing climate (MedSeA) project was the first concerted effort to study ocean acidification in the Mediterranean Sea, a highly populated region with complex and diverse physiochemistry and biology. Launched in February 2011, the MedSeA project originally consisted of 16 partner institutions and additionaly 5 associated partners joined the consortium during the project development. The MedSeA consortium institutions, located in 12 countries, mainly from the Mediterranean region, comprised over 120 scientists with the overall goal of assessing the chemical, climatic, ecological, biological, and economic changes of the Mediterranean Sea driven by increases in CO2 and other greenhouse gases. MedSeA was cofounded by the European Commission with a contribution of 3.49 M € and a total budget of approximately 6 M€ and run for 3.5 years.

MedSeA Overall objectives
The emphasis of the MedSeA research work has been put on the combined impacts of ocean acidification and warming on endemic calcifying species and related biogeochemical processes, in order to detect changes in calcification, fitness, productivity, biodiversity and the functioning of the food web. The MedSeA approach has been fully interdisciplinary, involving biologists, earth scientists, applied modellers and economists, using field observations, laboratory and mesocosm experiments, as well as formal models.
The MedSeA main objectives can be summed up as follows:
• Identify where the impacts of acidification on Mediterranean waters will be more significant, taking into account the complete chain of causes and effects, from ocean chemistry through marine biology to economic costs.
• Focus on selected sets of key ecosystems and socio-economic variables that are likely to be affected by both acidification and warming, studying the combination of effects through ship-based observations, laboratory and mesocosm experiments, physical-biogeochemical-ecosystem modelling, and economic analysis.
• Provide best estimates and related uncertainties of future changes in Mediterranean Sea pH, CaCO3 saturation states, and other biogeochemical-ecosystem variables, assessing the changes in habitat suitability of relevant ecological and economically important species.

MedSeA main research structure
The MedSeA’s strategy focused on a selected set of key ecosystem and socio-economic variables that are likely to be affected by both acidification and warming, studying the combination of both effects through ship-based observations, laboratory and mesocosm experiments, physical-biogeochemical-ecosystem modeling, and economical analyses. MedSeA organised its activities around the following main themes:
I. Past and present carbonate system dynamics. Carbonate system data in the Mediterranean Sea were very scarce when strating the project. New field measurements of the carbonate system variables, both in the Western and Eastern basins were provided as well as time-series measurements of the present-day carbonate system. These new data provide a solid basis for understanding the temporal evolution of the penetration of anthropogenic carbon into the Mediterranean Sea.

II. Pelagic and benthic community responses to ocean acidification and global warming. The MedSeA project defined the susceptibility and resilience of key-stone species and endemic ecosystems to Mediterranean acidification and warming. We assessed the effects that acidification have or will have on Mediterranean pelagic and benthic selected species and examine effects on potentially sensitive processes such as photosynthesis and calcification using: 1) plankton monitoring at selected time-series stations and regional cruises to characterize present conditions, 2) laboratory experiments, to gain information on the response of single species and strains, 3) mesocosm experiments, to determine the biogeochemical and community responses, 4) experiments in areas naturally acidified by CO2 vents to determine the long-term effects of acidification across multiple generations of marine organisms. In order to investigate the key groups and processes, we have selected the organisms and ecosystems that are most likely to be susceptible to acidification in the Mediterranean. The model species and processes which have been selected whether or not they are unique or endemic to the Mediterranean Sea, major contributors to habitat building, major contributors to ecological function, or species of economic value in the Mediterranean region.
III. Modelling-projected acidification and warming, and their impacts on ecology. Future projections of changes in Mediterranean Sea carbonate chemistry were performed using two ocean models, coupled with state-of-the-art biogeochemical models. During the 20th century, models were forced with fields from regional climate models driven by observed changes in atmospheric greenhouse gases. Model skill and bias were assessed by comparing simulated biogeochemical variables for the current state to available datasets. Model projections allowed us to construct basin-scale sensitivity maps to ocean acidification, based on combined changes in key model state variables (e.g. pH, CaCO3 saturation states, O2, temperature, stratification). The integrated analysis of these maps, helped the MedSeA scientists to identify the regions of the Mediterranean Sea that are expected to be more vulnerable to acidification under future climate scenarios. To move this investigation from the level of biogeochemical response to the ecosystem level, one task was dedicated to constructing response functions of selected target species (e.g. Posidonia medow, coralligenous habitats, red coral Corallium rubrum) to environmental parameters. This produced hybrid habitat suitability patterns, i.e. a range of projected variations of the stress factors for growth and functioning of the target species. This information were further exploited to assess socio-economic impacts associated with each considered target species, with a special focus on market species.
IV. Socio-economic effects of ocean acidification and potential adaptation strategies and policy tools. Direct effects of ocean acidification and warming were assessed for the first time first time on tourism and aquaculture for selected areas. These studied included information obtained by valuation studies addressing use and non-use values. Meta-analyses and benefit/value transfer studies were used in some cases, like the lost nursery value of seagrasses or corals. In other cases, the assessment included partial equilibrium analysis (PEA), which addresses both market impacts (notably on tourism and aquaculture) and non-marketed impacts (ecosystem values, including cultural services and non-use values such as option, existence and bequest values). The reduction of pH may result in loss of Mediterranean marine biodiversity, which would probably affect use and non-use values associated with both species diversity and particular unique Mediterranean ecosystems. Loss or degradation of coralligenous environments due to a pH reduction and increasing sea surface temperature could also have negative socio-economic impacts in regions that attract tourists for recreational diving, bathing, and viewing from underwater observatories or glass-bottom vessels. First adaptation strategies and policies were formulated on the basis of the qualitative and quantitative assessments by the natural and social science studies in the project.
Themes III and IV, modelling and socio-economic impacts, were transversal components, whose contents and objectives overlapped with the other themes. The overall MedSeA work programme consisted of three phases interlinked within the different themes:
Phase 1: Examination and reinterpretation of existing data from the Mediterranean Sea.
Phase 2: Obtaining new observational and experimental data.
Phase 3: Projecting future changes and related uncertainties.
At the level of project dissemination, MedSeA sought to raise awareness on the issues of ocean acidification and warming in the Mediterranean Sea through targeted presentations of such phenomena in the Mediterranean Sea and extensive communication of project’s results and findings to national, regional and international stakeholders.

Project Results:
The sections below are organised in two main parts. The first part contains an introduction summarising the main outcome in terms of performance/research indicators (research publications, presentations at international conferences, workshop and symposia) and the second section mainly present the main progress and highlights within each project research workpackage. The 4 main project themes relate to the following Research and Technology Development (RTD) MedSeA work packages:

I. Past and present carbonate system dynamics (WP2)
II. Pelagic & benthic community responses to ocean acidification and global warming (WPs 3 and 4)
III. Modeling projected acidification and warming, and their impacts on ecology (WP5)
IV. Socio-economic effects of ocean acidification and potential adaptation strategies and policy tools (WP6)

MedSeA main progress
MedSeA was launched in 2011 when there was a consistent lack of field-derived and experimental information on the Mediterranean ocean acidification and related ecosystem components. A substantial effort was required to collate the few existing data and new information from the pelagic and benthic systems. The specific oceanographic features of the Mediterranean basin were assessed using high-resolution, physical-biogeochemical models to provide basin-wide and surface-to-deep distributions of pH and carbonate-related variables. The models allowed us to project such changes into the future following established scenarios for atmospheric CO2 emissions. MedSeA experimental and field observations were shared in a comprehensive overall data management. The combination of the model projections with results from field and laboratory experiments and the socio-economic analyses allowed us to build vulnerability maps and possible economic impacts due to acidification in the Mediterranean.
This project was the first coordintated effect aiming to offer a comprehensive view on the physical, biological and socio-economic impacts of ocean acidification in the Mediterranean area using a so-called scale-basin approach. During the 3.5 year duration, MedSeA has generated a large number of critical data. 105 peer-reviewed articles were published or are currently in press. They led to over 420 dissemination activities including 255 presentations at meetings (163 oral presentations and 92 posters) (from February 2011 to September 2014) The project greatly contributed and stimulated ocean acidification research in the Mediterranean Sea. Every ten publications on Mediterranean Sea acidification during the period January, 2011- September, 2014, an average of six were a MedSeA contribution. A summary of the major scientific results is presented in the next sections.

Work Package 2, Past and present carbonate system dynamics (WP leader: Catherine Goyet)

The aim of WP2 was to assess the impacts on the carbonate system’s parameters of (a) ongoing, recent (100 to 10 years ago) and past (>103 years ago) changes in the Mediterranean Sea’s water mass circulation; and (b) anthropogenic CO2 forcing and much older changes in the atmospheric CO2 levels over a range of time scales (i.e. glacial to interglacial). Continuous sampling and measurements in time-series stations and along transects in key sites of the Mediterranean Sea (western and eastern basin) constituted the observational component of the carbonate system properties characterizing the area. Past variability in ocean chemistry was studied via paleo-reconstruction methods on marine sediment archives focusing on calcifying organisms such as foraminifera or coccolithophores.
The analysis of historical (existing) data from the Mediterranean Sea confirmed that according to general spatial features of seawater carbonate system properties, the total dissolved inorganic carbon (CT) is higher in the western basin, the total alkalinity (TA) is higher in the eastern basin and the anthropogenic carbon has already penetrated all the waters of the Mediterranean Sea. When the project was launched in 2011, no published paleo-reconstructions of Mediterranean carbonate system parameters were available. MedSeA provided for the first time this type of data and new insight of the pre-anthropogenic dynamics and timing of the Mediterranean carbonate system during the Quaternary.
The results point out that there is no Cant-free water within the Mediterranean Sea. This semi-enclosed sea stores a large amount of Cant, particularly in the western basin (Cant > 48 µmol kg-1 in the south of the western basin and > 21µmol kg-1 in the north of this basin). This fact could be explained by the thermodynamics: the low Revelle factor, due to warm waters and high TA, facilitates the absorption of atmospheric CO2, making the Mediterranean Sea a source of total inorganic carbon to the Atlantic Ocean. It indicates that Cant is efficiently transferred from the atmosphere to the Mediterranean Sea. Furthermore, it shows that this sea absorbs anthropogenic carbon faster than the open ocean. The most acidic waters in the Mediterranean Sea (the intermediate and deep waters of the western basin) have the lowest pH values and are highly contaminated by Cant. These results highlight the tight correlation between the absorption of the anthropogenic CO2 and the decrease of pH in seawater.
In order to assess the human-induced changes on the Mediterranean carbonate system properties (pH, AT, CT, and CO2 partial pressure (pCO2)), it is necessary to determine the initial conditions and in particular the estimations of pre-industrial CT. Since it is impossible to measure the pre-industrial CT we use results from the determination of anthropogenic carbon to estimate it. Results indicate that pre-industrial pH fields throughout the Mediterranean were higher than today (up to + 0.15 in the Western basin and up to 0.10 in the Eastern basin.
The level of acidification is significantly high in the Mediterranean Sea: all water masses sampled in the Mediterranean Sea (even the deepest) already suffer from acidification. All the data analyzed from time-series stations, especially those from the point B, clearly show that acidification is at its maximum in the surface layer. Despite a strong seasonal variability due to exchanges at the air-sea interface, we estimated a significant mean increase of acidification of 0.0017 ± 0.006 pH unit yr-1 since 2007. These time-series data are very important to assess the acidification in the surface layer because all indirect approaches that exist to estimate acidification from anthropogenic carbon are not valid in the mixed layer because of the potential biological activities. The intermediate layer (Levantine Intermediate Waters and the upper portion of the Eastern Mediterranean Deep Waters (EMDW)) appears to be the less acidified but the maximum for ΔpH encountered in the layer is not more than -0.06 (year 2001) (Touratier et al., in prep). All deep waters, EMDW and especially the WMDW, are characterized by increasing levels of acidification (pH is already < -0.12). This rapid increase of acidification is the direct consequence of deep convection in the open sea areas and also cascading of dense waters along the continental slope, i.e. the two main physical processes that allow the rapid and intense invasion of Cant from sea surface up to the deepest layers.

In order to evaluate the variability of the Mediterranean carbonate system prior to the instrumental records and across intervals of elevated atmospheric CO2 forcing (last deglaciation) and of profound changes in the basins thermohaline circulation (last interglacial period) sediment cores from the western, central, and eastern Mediterranean have been analyzed. The records of planktic foraminiferal δ11B and B/Ca used as proxy for paleo pH and their shell weight, spanning the last deglaciation have been generated, respectively, from one western Mediterranean (MD99-2346, 42.04N 4.15E 2100 m water depth and one eastern Mediterranean sediment core (MD84-629, 32.04N 34.21E 745 m water depth) document sea surface pH and planktic calcification decreases in both sub-basins of the Mediterranean Sea during the last deglacial episode of glacial-interglacial CO2 rise. These datasets are complemented by contemporaneous records of coccolith assemblages and calcite mass have been generated, respectively, from another western (ODP Site976, 36.12N 4.18W 1108 m water depth) and a central Mediterranean (ODP Site963, 13.10N 37.02E 469.1 m water depth) sediment core, indicating a decrease in the calcite mass of the ubiquitous coccolithophore species Emiliana huxleyi between the last glacial maximum and the Holocene. Planktic foraminiferal boron isotope results from core LC21, in the south-eastern Aegean Sea (35.40N; 26.35E; 1522 m water depth), complemented by a record of E. huxleyi calcite mass indicate that sea surface pH decreased at the onset of the last interglacial sapropel event, reduction of the eastern Mediterranean thermohaline circulation, in LC21 and that this change was accompanied by a decrease in coccolithophore calcification.
Seawater pH was also estimated in the Levantine Basin, Easter Mediterranean, in the core MD84-629 derived by B/Ca measurements performed on G. ruber. The reconstructed pH record was compared to the core tops values. The calculated pH values reveal that the last glacial maximum (LGM) surface Mediterranean pH is about 0.1 unit higher than the Holocene, which is the order of magnitude expected for glacial-interglacial pH changes.

Selected WP2 highlights
• All the waters of the Mediterranean Sea, even the deepest, are affected by anthropogenic carbon.
• Ongoing time-series measurements in the eastern basin show that the eastern basin is clearly characterized by AT>2600 µmol kg-1.
• Ongoing time-series measurements show that in the surface waters of the Northwestern Mediterranean Sea, the concentration of dissolved inorganic carbon increased by 3.4 ± 0.36 µmol kg yr-1 and pH decreases by -0.0016 ± 0.0012 unit yr-1 although these trends are not yet statistically significant. In contrast, pH normalized at the average annual temperature of 18°C significantly declines by -0.0017 ± 0.006 unit yr-1. At 50 m the pH decrease is of -0.0023 ± 0.0004 unit yr-1 but not yet significant while pH normalized at the average annual temperature of 18 °C significantly declines by -0.0020 ± 0.0005 unit yr-1.
• In the North Adriatic Sea, strong seasonal changes in seawater temperature are one of the main drivers of the high seasonal variations of pH, pCO2 and CT.
• Results from the trans-mediterranean MedSeA 2013 research cruise confirmed that TA, CT and surface pCO2 are higher in the eastern basin than in the Western Mediterranean Sea. Moreover, the eastern basin appears to be a significant source of CO2 for the atmosphere while the western basin is close to equilibrium.
• The determination of anthropogenic carbon in the Mediterranean Sea shows that pre-industrial pH fields throughout the Mediterranean were higher than today: up to + 0.15 units in the western basin and up to 0.10 units in the eastern basin.
• The fossil record of common planktic calcifying organism (coccolithophores and foraminifera) shows that their mass increases during periods of low atmospheric CO2 concentrations (glacials) and decreases during periods of high atmospheric CO2 concentrations (interglacials). However, the time scale of these mass responses is remarkably longer than the ongoing anthropogenic changes (on the order of several hundreds of years).
• These planktic calcifying organisms from sediment cores across the Mediterranean Sea show that sea surface pH reconstructions and planktic mass decreased during periods of atmospheric CO2 rise (i.e. during glacial-interglacial transition).
• The calculated pH values reveal that the last glacial maximum (LGM) surface Mediterranean pH is about 0.1 unit higher than the Holocene.

Work Package 3, Effects of ocean acidification and temperature on pelagic ecosystem functioning (WP leaders: Costa Frangoulis and Eva Krasakopolou)

The MedSeA WP3 assessed the effects of OA and warming on selected Mediterranean planktonic species (calcifying and non-calcifying) and on fundamental biogeochemical processes. During the project, WP3 researchers have gained information on physiological responses of single species and strains in several laboratory experiments conducted under manipulated carbonate chemistry, and temperature conditions (and in some cases, the combined effect of OA with nutrient limitation), and have studied the biogeochemical and community responses to acidification in experiments using large-scale in situ pelagic mesocosms, and land-based mesocosms. Further evaluation of biological data from the WP2 time-series stations operating in the Mediterranean basin and from field studies (including trans-Mediterranean research cruise) were performed.
New technologies and innovative approaches were developed and applied for controlling the conditions of warming and acidification for the needs of the laboratory and mesocosm experiments studying the individual and dual impacts of acidification and temperature on pelagic organisms and on marine communities and processes, respectively.
Therefore, besides the scientific knowledge acquired per se, concerning the impact of ocean acidification and ocean warming on marine biota, another major achievement of this WP was the knowledge transfer through training activities on planktonic species perturbation experiments, in parallel to the development of techniques (e.g. review on the best practice for thecosome pteropod culture techniques). This provided a comprehensive basis for future experimental work and culture system development on many types of different pelagic organisms going from virus to jellyfish, and exploring several temporal and spatial experimental scales (laboratory, land-based and pelagic mesocosms, in situ).
There is now robust evidence that many calcifying organisms, as well as non-calcifying organisms, are adversely affected by ocean acidification and/or ocean warming. There is considerable variability in sensitivity between closely related species or even between different strains of the same species, with some species being tolerant to ocean acidification in the range of pCO2 levels projected until the end of this century. The rapid warming will probably affect the plankton metabolism, community and ecosystem functioning earlier than acidification in an area such as the Mediterranean Sea that is generally very oligotrophic. However, the combined effect of these two stressors may enhance their consequences. In addition, it is still unknown how the effects of OA on planktonic calcifiers will propagate into the food web.

Selected WP3 highlights
• Laboratory experiments, long-term sediment trap series and observations in naturally high CO2 concentration sites (CO2 vents, off Vulcano, Italy) show negative impacts of ocean acidification on calcite mass and biodiversity of coccolithophores, a dominant calcifying phytoplankton group in the Mediterranean Sea.
• The planktonic calcifying community is dominated by coccolithophores in both western MedSeA mesocosm experiments (Corsica, summer 2011 & Villefranche, spring 2012).
• A large W-E gradient in foraminifera distribution number and size was revealed during the trans-Mediterranean MedSeA 2013 cruise; pteropods, although largely present, had a more scattered distribution
• Biometric comparison between modern pteropod shells and museum samples from 1910 and 1921 show that the latter were thicker and denser.
• Time series analysis (1967-2003) of pteropod population fluctuations in the NW Mediterranean (Point B) show no deleterious effect of declining pH but a 14-year periodic oscillation related to SST and indicating a possible influence of the North Atlantic quasi-decadal mode on pteropod populations.
• Experiments on the incorporation of boron in Orbulina universa (foraminifera) concluded that δ11B is controlled by pH, as expected, but that B/Ca is controlled by [HCO3-], which allows to fully reconstruct the carbonate chemistry beyond the ice-core record.
• The activity of primary producers has no significant effect on the carbonate system parameters and is not the driving force controlling their variability (Cretan Sea & Adriatic Sea).
• Ocean acidification does not evidently have direct effect on copepod (A. clausi) egg production and hatching success, with the possible exception of excretion. Warming resulted in an increase of excretion rate, an effect enhanced when combined with ocean acidification.
• Laboratory experiments on bacterial and viral community dynamics under acidification and warming conditions indicated that viral abundance was not considerably affected but bacterial abundance reached quickly high values under the acidified conditions.
• The increased glucose and oxygen uptake by a bacterial community in acidified and warm conditions suggest the presence of more glucose degrading bacteria. The bacterial community is slightly affected by pH changes.
• Microbial metabolism is not significantly affected by acidified treatments. Warming (but not OA) resulted in an increase in β-glycosidase activity towards the end of the experiment, pointing to a more intense degradation of polysaccharides.
• The effects of different pCO2 concentrations on exopolysaccharides production by Staphylococcus aureus indicated that the more the acidification of medium, the less the Staphylococcus aureus growth.
• Combined effects of OA and OW on Chaetoceros gracilis (diatom) show a decrease of growth, an enlargement of the cell, chloroplast damage, disorganization and disintegration of thylakoid membranes and cell lysis.
• Alexandrium minutum (harmful algae) cell growth is reduced with the decrease of pH. However, in combination with warming, growth at future pH was substantially increased compared to growth at present pH.
• The polyp asexual reproduction of C. tuberculata (symbiotic jellyfish) is highest in elevated temperature conditions, followed by lower pH and lower pH/elevated temperature conditions suggesting that ocean warming could be beneficial for their proliferation and acidification leaves them unaffected.
• The ‘statoliths’ morphology of the two scyphozoan adult species Aurelia aurita and Cassiopea andromeda is sensitive to reduced pH, possibly causing a lesser ability to orient in the water column.
• Mesocosm experiment results show that for CO2 conditions forecast for the end of this century, the pelagic ecosystem in both the western and eastern Mediterranean Sea will prove in general resilient to increases in the ocean acidification effect. However, the warming will have a more important effect than acidification; and that will enhance the effect of acidification on pelagic ecosystem functioning. However there was some indication of enhanced nitrogen fixation in the Corsica mesocosm experiment under warming and strongly acidified conditions.

Work Package 4, Effects of ocean acidification on keystone benthic ecosystems and the impact on benthic biodiversity (WP leader: Maoz Fine)

Work Package 4 aimed at assessing the response of Keystone Mediterranean benthic ecosystems to ocean acidification and climate change. Four iconic ecosystems were identified as the focal points of WP4 team: seagrass meadows, vermetid reefs, coralline algae seabeds and coralligenous reefs. A further goal of WP4 was to examine the response of commercially important species (red corals and mussels) to the projected conditions. The state of the keystone benthic ecosystems was characterised at Mediterranean level, identifying possible risks under OA and warming and assessing the physiological responses to a changing environment in situ, in controlled laboratory experiments and in three Mediterranean CO2 seeps: Methana (Greece) Ischia Island and Vulcano island (Italy).
Posidonia oceanica is negatively impacted by the effects of global warming over the next century and climate change poses a significant challenge to this seagrass that is already suffering losses from anthropogenic impacts. Warming can induce declines in shoot abundance through increased shoot mortality in P. oceanica meadows. Younger life-stages (i.e. seedlings) of P. oceanica may be particularly vulnerable to climate change. Insights into OA effects on seagrasses has come from CO2 vent surveys: showing consistent loss of crustose coralline algal epiphytes on seagrass leaves, and greater seagrass density close to the seeps with a lower pH. Lower epiphytes load can have positive consequences for seagrasses as it reduced shading and nutrient uptake by the epiphytes.
Vermetid reefs have reduced recruitment success of the main reef-builder snail Dendropoma petraeum, increased shell dissolution, and altered recruit shell mineralogy at expected levels of ocean acidification. Physiology of vermetids early-stages is affected by OA acting in concert with thermal increase. Benthic biodiversity associated to this ecosystem significantly differed at three pCO2/pH levels. Although vermetid are resilient to near-future pCO2 levels, it is likely that their reefs will not be able to withstand levels of acidification predicted for the end of this century, and the associated community will change as a result.
Laboratory cultures of coralline algae under conditions of elevated temperature and pCO2 revealed effects on photosynthesis, growth and calcification. Crustose coralline algae (CCA) (Neogoniolithon brassica-florida) dropped to half of its maximal photosynthetic yield at a relatively low light intensity (50 µmol quanta m-2s-1) compared with its natural light experience, only when exposed to near-future seawater temperature levels (33°C). Sensitivity of N. brassica-florida to OA examined in CO2 seeps showed no significant difference in the photosynthetic yield between pH sites except at 1500 µmol quanta m-2s-1 (mid-day) when Fv/Fm of N. brassica-florida at the low pH site was significantly lower than the medium and ambient pH. In the light (400 µmol quanta m-2s-1) at pH 7.9 CCA calcified at a rate half of that incubated at ambient pH 8.1. In the dark, CCA incubated in both pH levels dissolved with a much higher dissolution rate at pH 7.9. Cover of CCA decreased as pCO2 increased in CO2 seeps, confirming that calcifying algae are likely to be threatened by ocean acidification, especially those species living near their thermal limit.
The red coral Corallium rubrum, a key species of the coralligenous community with significant cultural and economical significance, showed no effects of OA on microdensity and porosity. Impaired sclerite shape and a 59% decrease of its calcification rate was found at lowered pH. Disturbances such as harvesting pressure could act in synergy with OA bringing local populations to extinction.
The assessment of the effects of OA and warming on mussel growth culture revealed that the
Mediterranean mussel Mytilus galloprovincialis is particularly sensitive to increasing temperature. A significant decrease in growth (total weight, shell length, shell weight) has been found in warmer conditions as well as clear dissolutions of the shells exposed to low pH conditions (-0.3 compared to ambient). Mussels exposed to low pH showed a clear loss in the organic layer covering the shell in summer, explaining the clear dissolution signal measured on these mussels.

Selected WP4 highlights:
• Thirteen sites in Sicily and five in Israel were inspected for Dendrepoma petraeum and its associated calcareous algae N. brassica-florida live cover. Vermetid reefs sites along the Sicilian coast were overall healthy, but no living D. petraeum was found along Israel coasts.
• Sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. The distribution of A. lixula was unaffected by the low pH environment, whereas densities of P. lividus were much reduced. There was skeletal degradation in both species living in acidified waters compared to reference sites and remarkable increases in skeletal manganese levels, presumably due to changes in mineral crystalline structure.
• Sponge percentage cover decreases significantly from normal to acidified vent sites. Increasing CO2 concentrations will likely affect sponge community composition as some demosponge species appear to be more vulnerable than others.
• Posidonia oceanica meadows are declining across the entire Mediterranean basin, with estimates of 13 – 50 % of P. oceanica already lost. Warming has a negative effect on P. oceanica seedlings, leaf biomass, leaf growth, leaf production and leaf longevity. Zostera noltii showed that both the maximum photosynthetic rate (Pm) and photosynthetic efficiency (a) were higher (1.3- and 4.1-fold respectively) in plants exposed to CO2-enriched conditions. CO2 vent surveys show consistent loss of crustose coralline algal epiphytes on seagrass leaves, and greater seagrass density close to the seeps with a lower pH.
• The calcification rate of Coralium rubrum when exposed to lower pH treatment is about 59% lower compared to control conditions. Microdensity and porosity of C. rubrum were significantly lower at reduced pH. The survivorship in each treatment was 100%
• Vermetid reefs have reduced recruitment success of the main reef-builder snail Dendropoma petraeum, increased shell dissolution, and altered recruit shell mineralogy at expected levels of ocean acidification.
• Mitylus galloprovincialis, commonly used in Mediterranean shellfish aquaculture is highly sensitive to increase seawater temperature causing a drastic increase in its mortality rates.
• Vermetid gastropods, seagrasses, corals, calcareous algae and bivalves are showing great sensitivity to ocean acidification and temperature rise. This may lead to a phase shift in benthic communities as these organisms are engineering species.

Work Package 5, Future projection of the acidification of the Mediterranean Sea (WP leader: Marcello Vichi)

The simulation of the Mediterranean Sea carbonate system under current climate conditions was performed in this WP. A set of coupled physical-biogeochemical model was forced with climate model data to project the impacts of anticipated future climate scenarios on pH and surface temperature. It focused on the assessment of numerical models under current climate conditions and the investigation of future projections of the CO2 system in Mediterranean using the RCP8.5 IPCC scenario. This scenario implies a maintained utilization of fossil fuel energy sources without any mitigation measure, with a resulting increase of the Earth radiative balance of 8.5 W/m2 at the end of this century.
The main products of this work-package were the projected changes in ocean physics, carbonate chemistry (pH, saturation state of aragonite) and the projected habitat vulnerability of selected iconic Mediterranean ecosystem components. The impacts of increasing acidification and climate change in the Mediterranean Sea addressed 1) the current basin-wide distributions of pH, carbonate saturation states, and related carbon-system variables and 2) the projected changes of these variables during the 21st century, both obtained through a small ensemble of coupled physical and biogeochemical models. These results supported the development of the socio-economic vulnerability maps and provided reference values to implement policy tools to tackle future acidification and warming scenarios within the work-package 6.
The 50-year climate projections of Mediterranean physical and biogeochemical variables clearly show that the Mediterranean Sea will be warmer of 1 to 1.5°C more than the year 2000 and more acidic of another 0.1 pH units, with regional intensification of the warming signal in the Eastern Mediterranean, Aegean and Adriatic Sea. These projected variations of climatic conditions combined with scenarios of changes in land use will likely cause a decrease in upper layer nitrogen concentrations, which together with small changes in phosphorus availability and changes in water temperature will project a moderate decrease of plankton productivity in the western part of the basin, partially compensated by a small increase in the Eastern Mediterranean Sea. The iconic Mediterranean habitats for Posidonia oceanica meadows, coralligenous habitats, maërl beds, and red coral (Corallium rubrum) banks were selected to study their vulnerability to the projected future changes in ocean acidification, biogeochemical conditions and mean temperature from the numerical models. Specialized numerical models based on in situ and laboratory biological experiments have been used to compute the species-specific vulnerability of the response to the projected changes in selected key environmental variables such as temperature, pH, nutrients and alkalinity. Results highlight a decrease in habitat suitability for all species considered under the simulated future conditions. Also in the case of Posidonia, model projections overall suggest a decline in suitability under future conditions.
The changes in the occurrence probability obtained by differences between present conditions and future scenarios show that the projected extent of potential mortality zones is higher than in the current climate for red coral and that there is a loss of probability of coralligenous formations along the Mediterranean sites mostly due to acidification increase (Fig. 9). The adverse impact is however localized to certain regions: it is also reported an increase of probability of the presence of coralligenous in the North Aegean and Northern

Selected WP5 highlights
• Multi-model projections point toward an average surface warming from 1 to 1.5°C in the Eastern Mediterranean, Aegean and Adriatic Sea between 2000 and 2050;
• Summer surface temperature is very likely to persistently exceed 29°C in the Levantine basin by the end of 2050;
• Future scenarios on the Mediterranean Sea acidification agrees on a potential reduction of another 0.1 pH units during the first half of this century, consistent with model estimates for the global-ocean average;
• The major contributors to uncertainties associated with estimates of carbonate system variability include the lack of data to better constrain numerical model initial conditions and external forcing.
• Surface waters are likely to become unfriendly to coral growth by mid century with an expansion of potential mortality areas: projections estimate a relatively small reduction in yearly calcification, which has the potential to become substantial if extrapolated through the whole lifespan of long lived species such as Corallium rubrum
• The use of habitat suitability models combined with the future projections of changes in acidification and environmental conditions predict a general loss of probability of presence of coralligenous formations along the Mediterranean sites with some localized increase of in the North Aegean and Northern Adriatic Sea
• The natural variability of pH and environmental conditions in the Mediterranean is rather large, due to the presence of contrasting coastal and open ocean environments and the ample seasonal change in temperature typical of mid-latitudes marine systems. It is likely that local effects may offset the overall acidification, but in the longer term the pH will diminish without a reduction of global CO2 emissions.

Work Package 6, Socio-economic effects of Mediterranean Sea acidification, adaptation strategies and policy tools (WP leader: Jeroen van den Bergh)

Acidification and warming of the Mediterranean Sea will lead to substantial impacts on regional marine-related economic activities. MedSeA WP6 performed the first Mediterranean basin-scale study on acidification and warming implementing both market and non-market valuation to capture the full range of economic losses. These losses may comprise effects on important sea-based sectors, such as beach and diving tourism, and bivalve mollusc aquaculture. Additional benefits at stake include the potential disruption of ecological processes such as carbon sequestration and coastal protection, as well as effects on non-use values associated with the perceived environmental health status of iconic Mediterranean species and habitats.
WP6 successfully completed the elaboration of a methodological approach for the economic valuation of the socio-economic costs associated with ocean acidification. This involved understanding the chain of impacts generated by ocean acidification for a broad category of ecosystem services with economic significance, and identifying the appropriate set of economic non-market and market valuation techniques for the assessment of ocean acidification costs. In addition, the development of a hybrid ecosystem-based valuation approach to assess ecosystem damages, including the economic valuation of carbon sequestration services in the context of acidification in the Mediterranean Sea, and a macro-economic analysis of indirect effects in the context of fisheries and tourism.
Next, an assessment of recreationists’ preferences regarding the quality of certain natural features vulnerable to ocean acidification and sea warming was undertaken. This included the potential recreational losses due to scenarios of higher presence of jellyfish species and degradation of iconic marine species and habitats (e.g. red coral, and coralligenous habitats). Economic valuation studies were performed in Mediterranean areas of considerable tourism significance, with the purpose to extrapolate the findings to similar regional areas in the Mediterranean. Finally, a questionnaire-based survey was targeted at Mediterranean mollusc aquaculture producers to characterize the environmental pressures related to climatic and non-climatic factors they are subject to.
The data collected in WP6 provided the basis for identifying a range of adaptation strategies, tools and policies to limit negative socio-economic impacts of acidification on the Mediterranean region.

Selected WP6 highlights:
• Total yearly benefits of carbon sequestration/buffering in Mediterranean EEZs are 2.51 billion € for 2000 – 2009 and 4.15 billion € for 2030 – 2039. These values are calculated using a carbon price of 19€/ton CO2 recommended by the EC (DECC 2009). This is likely to be an underestimation, and if recent estimates of the social cost of carbon are used then benefits might be up to 6 times higher.
• The macroeconomic benefits of marine carbon sequestration (buffering or compensation) are a 6% reduction of the negative impacts of climate change on fisheries and tourism.
• The results of a valuation study of the impact of outbreaks of jellyfish blooms due to increases in seawater temperature on coastal leisure activities in the city of Tel Aviv, and by extension along the entire Mediterranean shoreline of Israel, indicate that on an annual basis a monetary loss results in the range of 8.9–31.1 million ILS (1.8–6.2 million €). Associated with this is a reduction in the number of beach trips between 3% and 10.5%.
• Estimated values of a “risk of jellyfish outbreaks” indicator for each of the six sub-basins that compose the Mediterranean Sea indicate that the highest level of risk to recreational activities is found in the “Sardinia and Gulf of Lyon” sub-basin. A medium risk is found in the Levantine and Balearic basins. The lowest risk levels are predicted for the Aegean and Adriatic Seas. Since such results are largely controlled by the distribution of the available monitoring operational areas, they should be considered of a preliminary nature and be complemented by information based on more extensive monitoring in the future.
• A study was undertaken in Catalonia, Spain to assess economic use values associated with diving tourism as affected by marine ecosystem changes due to climate change and ocean acidification. It shows that scuba divers require a high compensation to dive in areas where gorgonians have disappeared, namely 72 € per dive, resulting in a total of 4 million € for the total of dives made in a year. Jellyfish are, depending on the type of species (stinging or not), considered as repulsive or attractive to divers. Avoiding stinging jellyfish has an additional value of 1.7 million €.
• Ocean acidification may trigger changes in the suitability of the coralligenous habitat and red coral mortality in various parts of the Mediterranean Sea. Among the studied areas, there are some highly intense diving destinations such as Calanques (France), Medes (Spain) and Portofino (Italy), with 30,000 up to 150,000 dives made in a year. A rough estimate can be derived for the compensation value of impacts of sea warming and ocean acidification for all MPAs in the Mediterranean Sea area, namely to be in the range of 150 thousand to 120 million Euros.
• A survey of mollusc aquaculture producers from different Mediterranean Sea areas showed that a great majority of the respondents (76%) have experienced important difficulties in their activity in past years as a consequence of summer heat waves. These events have led to various sorts of effects with negative economic repercussions, such as juvenile and adult mortality of molluscs, and a decrease in the production of byssus. The results further indicate a high uncertainty and lack of knowledge among producers regarding what ocean acidification could mean for the future of their sector. Effects such as a decrease in shell resistance and thickness and diminished seed recruitment, which are likely to occur under continued ocean acidification, already have been observed in some production sites.
• Mitigation strategies and policies at global, regional and local scales need to be implemented as they are the only certain, effective way to reduce CO2 emissions to the atmosphere and associated ocean acidification. Mediterranean Sea acidification may be more severe in areas where human activities and impacts, such as nutrient run-off from agriculture, further increase acidity. Agricultural run-off from land and other stressors on Mediterranean ecosystems needs to be more strictly regulated. In addition, adaptation policies are required as an increase in atmospheric CO2 concentration seems unavoidable. The combination of mitigation and adaptation can assure that the Mediterranean can continue to sustain livelihoods, provide food and protect shorelines.
• Adaptation includes a wide variety of strategies: (i) making marine ecosystems more resilient by improving diversity through establishing marine protected areas; (ii) reducing local stressors (land-based pollution, coastal development, overharvesting, and invasive species) by regulating sectors like agriculture, industry and infrastructure; making marine ecosystem based sectors like fisheries, aquaculture and tourism more resilient to sea warming and ocean acidification by creating awareness and providing public assistance; and undertake marine spatial planning addressing unique threats to shorelines, estuarine, shallow coastal zones and deep waters. In addition, contentious bioengineering approaches are proposed, like dissolving carbonate minerals (e.g. limestone) in seawater or iron fertilization stimulating photosynthesis and hence carbon uptake. All of these, however, have serious drawbacks and risks.

Potential Impact:
In the MedSeA project, we raised awareness of OA in the Mediterranean region through contributions to major scientific assessments (e.g. IPCC-AR5, CBD-Technical Serie-75, SGOA-OSPAR) as well as documents for policy makers and outreach in different Mediterranean languages. MedSeA is one of the first international cooperative research projects on OA and warming within a European funding framework following the first internationally leading project on OA, EPOCA (European Project on Ocean Acidifcation). MedSeA is the first to deal specifically with the Mediterranean Sea and involved from the beginning to end several partners from Europe’s Southern Neighbourhood. The breadth of its empirical endeavour, its research achievements, and its multi-scenario interdisciplinary output would have been unattainable without its international membership; the comprehensiveness and reliability of its analytical and experimental work would have been compromised without the constant inclusion of MedSeA’s Southern Mediterranean partners.

The dissemination on the risk of the Mediterranean Sea acidification was developed within the work package 7 (WP leader: Carol Turley PML), aiming to better inform policymakers and other stakeholders in the Mediterranean region about the risk of OA in the Mediterranean Sea. It did so through systematic dissemination and awareness activities aimed at increasing the visibility of OA and warming as key components of climate change phenomena and a source of significant risk for marine ecosystems in the Mediterranean area. Overarching activities were also performed in the project management (work package 1) through the project websites and specific blogs. The project web page and the social networks (e.g. blogs) showing key project activities were instrumental for communicating and reaching out to a large audience and provide products for students and teachers. The website ( had almost 200.000 views from 2011 (March) to 2014 (September), the majority of which were from Mediterranean countries, North and South America and Australia. An information outlet was maintained on Mediterranean climate and environmental change ( providing a service for the diverse scientist and projects working on the marine climatic and non-climatic marine environmental change. This blog had over 1680 posts receiving over 30.500 views from February 2012 to August 2014. Key activities such as mesocosm experiments (e.g. and the oceanographic cruise were well covered in blogs and followed. For example the MedSeA oceanographic cruise blog ( in May 2013 had in one month over 17.000 views.
This section 4.1.4 reports on the impacts and outcomes of MedSeA: a) on European and international research in the field of OA and warming; b) on the community of stakeholders and policy-making directly involved or affected by the results and output of MedSeA’s research and analytical work; and c) on society at large, emphasizing both the ability of MedSeA partners to reach the wider public with their dissemination activities, and the relevance of MedSeA’s results and outcomes in terms of economic and societal impact. Impact on European and international research

The MedSeA project has had a significant impact on European and international research on ocean acidification, ecosystem conservation, and warming and climate-change effects in the Mediterranean area. As shown above, much of the most recent state-of-the-art scientific knowledge produced on these topics can be ascribed to the work of MedSeA partners and researchers. The MedSeA Project planned to positively affect European and global research on these topics by giving emphasis to three key roles: as coordinator of unrelenting communication among the partners and exchange of ideas and scientific material and data; as liaison between MedSeA researchers and international fora and consortia with international visibility and outreach on the topic of ocean acidification; and as scientific and institutional hub for the mobility and involvement of young researchers at various levels (PhD students, Post-docs, and junior researchers), from partner institutions as well as from a number of European, North African and Middle Eastern universities and research centres, and other institutions from around the globe.

The MedSeA project has served as a platform to coordinate the work of the sixteen partners that took part in the project and the 6 associate partners joining the consortium during the project. Constant collaboration across the consortium has offered MedSeA many opportunities for transnational academic efforts that have enhanced the visibility and impact of MedSeA-related knowledge and research output. Even beyond the added value of transnational research work in a number of experimental settings that spread across the whole Mediterranean region, MedSeA has been a unique opportunity to create synergies between institutions that have relied extensively and mutually on each other to advance their individual progress into a collective academic endeavour, with an impact that transcends the Mediterranean and increases knowledge on a phenomenon — ocean acidification and warming — with truly global consequences. In scientific terms, the result of this enhanced collaboration can be quantified in 105 published peer reviewed articles, allowing MedSeA-related research on ocean acidification account for an average of 60% of all published research on ocean acidification in the Mediterranean area throughout the project’s duration. These results were presented to relevant scientific audiences in international conference and events throughout the duration of the Project, allowing MedSeA researchers to obtain feedback at the highest level and engage the scientific community on further commitment to the study of ocean acidification and its effects. MedSeA European and international academic activities include 255 presentations at conferences and workshops, and an assiduous activity at several outreach events with posters, stands, and other dedicated dissemination means. Moreover, all the data collected throughout the project, in its fieldwork will be made available through the PANGAEA ( information system, a collective open-access library and database to archive and publish geo-referenced data from research on the earth system: the data is available for consultation and issued under an open-access creative commons licence. In its 2012 communication on the European Research Area (ERA), the European Commission emphasised several key objectives that were crucial to promote growth through knowledge and research and improve the productivity of scientific research with positive externalities on job creation and economic development. Among these goals, the Commission mentioned explicitly the need for more effective national research systems and the optimal circulation, access to and transfer of scientific knowledge via a digital European research area. The scientific output of the MedSeA project, the outcomes of its three-year-and-a-half long multinational collaboration scheme, and the reliance on Europe-wide infrastructure to make this knowledge accessible to the scientific community and the larger public make the MedSeA Project particularly consistent with the guidelines and compliant with the overarching strategy that the European Commission has defined for the next few years in Europe’s research agenda.
MedSeA (WP leader, UAB, data curator, Michael Grelaud) has maintained two data bases, one on observational and experimental data, and the other on modelling data. The MedSeA data management consisted of two parts: (1) the management of data created by MedSeA and (2) the archiving of all the environmental and biological data published within the project. Most of the data produced during MedSeA have been archived in the information system PANGAEA ( where they are in open access. The data can be accessed as well from MedSeA web site ( The data originated from continuous time-series (DYFAMED, Point B, POSEIDON E1-M3A, C1-LTER) were not archived on PANGAEA in order to avoid duplicates: they are freely accessible, on request; from different national data centers.

MedSeA database consists of 79 datasets. The largest portion of data sets originated from in situ observations, including a total of 36 data sets (more than 72000 data points) which were presented in 16 scientific articles. Laboratory experiments are the second data sets providers. They focused on many different groups of organisms (corals, bacteria, phytoplankton, zooplankton, bryozoans, echinoderms and mollusks) and produced 23 data sets (more than 86000 data points) presented in 14 scientific articles. The three mesocosms experiments gather 5 data sets; they include more than 150 parameters and represent an amount of more than 190 000 data points. The paleo studies produced 11 data sets (mainly from the analysis of marine sedimentary archives) presented in 5 scientific articles. Finally, physical oceanography from the 2013 MedSeA-GEOTRACES cruise is also represented in the MedSeA database, including a total of 3 data sets and more than 220000 data points.
The project’s model output archive will be release very soon and will be available on PANGAEA as well. The MedSeA simulations consist on coupled models NEMO+PISCES and NEMO+BFM.

Throughout its duration, the MedSeA Project has also emphasised the need for more effective networking and knowledge-sharing across the scientific community actively involved in research, dissemination, and policy counselling on ocean acidification, warming, and climate change. MedSeA was endorsed by IMBER (Integrated Marine Biogeochemistry and Ecosystem Research, an international project initiated by the International Geosphere-Biosphere Programme (IGBP, and the Scientific Committee on Oceanic Research (SCOR, that studies impacts of natural climatic and anthropogenic influences on marine biogeochemical cycles and ecosystems, their interactions, and feedbacks to the human and Earth systems. MedSeA was also endorsed by SOLAS (Surface Ocean Lower Atmosphere Study, an international research initiative studying the key biogeochemical-physical interactions and feedbacks between the ocean and atmosphere, and how these factors regulate climate and global change. Participation in IMBER/SOLAS events has guaranteed MedSeA scientists and researchers a globally-renowned forum through which channel MedSeA advances and achievements, while significantly contributing to the efforts of the international academic community in the definition of a scientific and policy agenda to tackle acidification impacts on a larger scale. Cooperation with other European and international research frameworks, projects, and schemes was a key feature of MedSeA’s research and dissemination strategy. Collaborations include dissemination actions and feedback coordinated with the UK-OA Programme on ocean acidification; dissemination and training activities with the BIOACID national German research project; MedSeA was a key partner in the development of the OA-ICC (Ocean Acidification International Coordination Centre (OA-ICC), funded through the IAEA’s Peaceful Uses Initiative) based activities on dissemination and communication about ocean acidification worldwide. MedSeA is a founding partner of this International Atomic Energy Agency initiative and the Project Coordinator as well as other members are parts of the OA-ICC’s advisory board; acknowledgment in the Inventory of EU Marine Climate-Change Research through cooperation with the CLAMER (Climate Change and European Marine Ecosystem Research) project; the PEGASO (People for Ecosystem based Governance in Assessing Sustainable development of Ocean and coast) project, with feedback on larger public and policy-makers/stakeholders; the PERSEUS (Policy-orientated marine Environmental Research for the Southern European Seas) project, with exchange of scientific counsel between the project coordination offices and attendance in MedSeA projects’ annual meetings; the MedPartnership Project, set up by the UN Environmental Programme, to which MedSeA contributed as invited member of the Scientific Steering Committee; a coordinated session at the 40th CIESM (Mediterranean Science Commission) conference in Marseille, on October-November 2013; and the participation in the Ocean Acidification Principal Investigators’ Meeting in Washington, on September 2013, in which the MedSeA coordinator was invited to present the project’s findings and achievements to researchers from key American institutions working on ocean acidification worldwide. As the European Commission highlighted in its ERA communication, optimal transnational co-operation and competition needs to be a pillar for the evolution and strengthening of a competitive research environment on a European scale: MedSeA’s extensive record of international and European collaborations throughout its duration is an additional proof of the project’s consistence with the overarching strategy and guidelines laid out by European institutions.

The MedSeA Project, finally, has played a fundamental role in the European academic landscape on marine environmental policy and acidification studies as a research hub for young scholars, junior researchers, and students. The added value of participating in the MedSeA project stemmed from its multinational nature and its ability to proactively engage the academia and the research communities of several non-EU states across the Mediterranean region. Shared research work and activities within the MedSeA project have effectively translated into a multidisciplinary experience that allowed students and young researchers from often distant or diverse contexts and backgrounds to get in touch with different academic traditions, instruments and techniques, and resources. Throughout its three-year-and-a-half duration, the Project has actively involved more than 43 junior researchers, including 16 PhD students, and 27 Master’s students and several joung postdtocoral researchers (over 25). Students and young researchers also benefitted extensively from the techniques and instruments that were funded by the MedSeA project to attain its results: research cruises across the Mediterranean, fieldwork experiments with cutting-edge technology, common platforms and events to update the consortium and discuss the use of relevant data all contributed to the inclusion of these categories in the Project and its achievements. Another pillar of the European Commission’s overarching research strategy is to ensure the removal of barriers to researcher mobility, training and attractive careers and create an open labour market for researchers. With the training opportunities, the options for mobility among the members of the MedSeA’s consortium, and the active involvement of young researchers in the work performed by all partner institutions, MedSeA has proved particularly consistent with another key instrument of the long-term vision of the European Commission for competitive and path-breaking research across Europe. Impact on stakeholder and policy-making communities

Since its initial phases, MedSeA has been relentless in engaging and involving the policy-making community and all the societal and economic stakeholders directly interested in ocean acidification of the Mediterranean Sea and its broader impacts. The knowledge acquired and developed through the MedSeA’s scientific work has added significantly to the information available to policy-makers at the European, national and local levels. This knowledge is all the more important in a context in which, globally as well as regionally, the negotiation of more stringent regulation and an adequate normative response to the challenges of climate change and warming is underway and rapidly turning into an extremely urgent, top-of-the-agenda issue at all governance levels.

Within the European context, the European Union approved in 2008 the first Maritime Strategy Framework Directive (MSFD, Directive 2008/56/EC) to establish a common European framework for a consistent marine environmental policy. In 2014, the European Commission started a tailored process of evaluation and assessment of the MSFD’s reception by each individual Member State while releasing, as recently as on May 2014, a new communication on the tight link between marine preservation, innovation, and economic growth. Marine environmental protection is key in the new research framework of the Horizon 2020 Programme, as the policy-making community now acknowledges the creation of new knowledge on marine ecosystems and an increase in investments in research on these topics as top priorities.

Because of this growing interest, since its initial phases, the MedSeA Project has invested significantly in constant communication with the policy-making community. A specific tool, the Mediterranean Reference User Group (MRUG), was conceived to institutionalise this channel of communication and enhance the opportunity for fruitful exchange of information, knowledge, and updates on the output and results of the MedSeA’s research work. Since 2011, the MRUG has met annually to define a strategy for the dissemination of acidification-related knowledge in the Mediterranean and beyond through a privileged information flow with interested stakeholders. Through its expanding membership, the MRUG has involved throughout the project’s duration representatives from UNESCO, the Union for the Mediterranean, the United Nations Environmental Programme, the World Bank, Greenpeace, the WWF Foundation, FAO, the Global Ocean Commission, Ocean Conservancy, and Europêche among others.

The MRUG undertook a laborious job of coordination across platforms, institutions, and different recipient communities. Its activity was valuable, nonetheless, in spreading awareness on ocean acidification, in tightening the bond with the policy-making community, and in fostering feedback, comment, and advice from the various stakeholders that see MedSeA as a key interlocutor in the definition of a truly European framework for the identification and fight against ocean acidification, warming and climate-change challenges in the region. The MRUG brochures were circulated at meetings and conferences of international relevance — including iOA-RUG events (International Ocean Acidification Reference User Group) and the framework of the EPOCA European research project.

MedSeA scientists, researchers and institutional partners all played a key role in disseminating information to a wider audience of stakeholders and policy-makers. Throughout its duration, MedSeA has circulated a number of press releases to reach the widest audience possible about the project’s achievements and results. Many MedSeA members have participated in meetings, workshops, and conferences at the international level that engaged and involved the highest level of governance representation in the fields of climate-change action and environmental policy. Within the project’s Work Package 7 on the dissemination on the risk of the Mediterranean Sea acidification, MedSeA members participated in events organised by, among other, the European Union, the French government, and the United Nations’ Framework Convention on Climate Change—mostly in the frame of the Rio+20 initiatives. The Project Coordinator was also actively involved in dissemination activities at the highest institutional level. In September 2013, she took part in the United States Ocean Acidification Principal Investigators’ Meeting, an event that gather all main researchers and responsible scientists from the United States currently working on projects related to ocean acidification, warming and marine climate-change effects. In March 2014, she participated in the EU-organised HOPE: Healthy Oceans, Productive Ecosystems conference in Brussels, under the auspices of the European Commission, on the relation between a healthy oceanic ecosystem and sustainability and growth. As a token of the perspective contribution of MedSeA to milestone knowledge in the field of ocean acidification and to future research efforts in this field, the MedSeA Project Coordinator has been personally invited to address policy officers from the European Commission and other European agencies at a lunch talk at the Directorate-General MARE, on November 18, 2014, following positive feedback on the successful MedSeA’s Policy Day at the European Commission on July 8, 2014.

Other relevant MedSeA scientists’ dissemination activities include the collaboration to the activities of the Intergovernmental Panel on Climate Change; the collaboration of MedSeA scientists — especially from Work Package 4 — in the drafting of the FAO’s report on ocean acidification impact on fisheries; the participation of several MedSeA researchers in the Convention on Biological Diversity as experts on ocean acidification in Europe; and a member of the research consortium invited to address the audience of the Our Ocean Conference, organised in September 2014 by the U.S. State Department and that featured a keynote intervention by Secretary of State John Kerry, on the effects and science of ocean acidification, warming, and the lessons learned from the European case.

The work of MedSeA scientists and partners in actively disseminating state-of-the-art knowledge and raising awareness on the comprehensiveness of the issue on society and the economy culminated, perhaps, in the elaboration of the Ten Policy Facts on Ocean Acidification in the Mediterranean Sea, a document that sums up the main findings, results, and impacts of the MedSeA’s three-and-a-half year research work in a clear, concise and direct way and that expressly addresses policy-makers (see Annex 1). Not only does the document provide policy-makers with all the necessary key information they need as guidance in the attempt to elaborate and perfect the European policy and legislation on ocean acidification, but it also synthesises the tight connection between the scientific component of the knowledge created throughout the project’s duration and the pervasive social and economic consequences that are likely to affect the day-to-day lives of European citizens. The Ten Policy Facts document was on of the key perspective outputs at the beginning of the project, and the result of constant feedback and negotiation across the project’s different work packages. The goal was to provide the largest possible audience of stakeholders with immediate answers to sensitive questions about acidification, its impact on the economy and society, and a sustainable way to design and implement solutions for the challenges it raises.

A scientific document — Ten Facts on Ocean Acidification — was developed at the same time to address the key priorities of academic research and knowledge building on the topic of acidification in the Mediterranean area, and was eventually presented at a dedicated press release, the coda of the Final Meeting that gathered all MedSeA partners in Barcelona on June 10-12, 2014. The Ten Policy Facts, on the other hand, were presented directly to policy-makers and stakeholders shortly after in Brussels, on July 8, 2014, during the MedSeA Project’s EU Policy Day, organised by the Directorate-General of Research and Innovation. The meeting, a dedicated session in which MedSeA researchers, principal investigators, and communication managers had the opportunity to address with no intermediation policy officers from various European Commission’s DGs and EU agencies—including DG MARE, DG Environment, DG REGIO, and DG Enterprise, among others. The audience was particularly consistent with the message the MedSeA had for the policy community: the need for further investment in research on ocean acidification and its impact; the necessary involvement of the Mediterranean area as a whole, empowering Southern and Eastern neighbours in the common struggle against climate change and the stressors that affect the multiplicity of Mediterranean ecosystems; the need for more transparent policy- and law-making in this field, and the big opportunity currently available to European legislators to influence national and global legislation on the topic by acting as first movers at least at the European level. The Ten Policy Facts document, the presentation of the project’s results, and the official MedSeA video, Testing the Waters, were welcomed very warmly as effective and incisive explanations of the current priorities and overarching research goals in the field of ocean acidification, warming, and climate-change action. As mentioned above, a representative of DG MARE invited the Project Coordinator to deliver a talk on the MedSeA project, its achievements, and a roadmap for future action to a larger audience of policy-makers and policy and economic stakeholders. Together with the possibility to circulate MedSeA materials at a higher policy-making level and to showcase the MedSeA video as a powerful tool of dissemination even with non-specialised audiences, the MedSeA EU Policy Day and the talk at the European Commission in November will be the summit of the MedSeA’s constant dissemination effort, and further evidence of the project’s involvement in the definition of the European agenda on ocean acidification in the nearest future. Socio-economic impact

One of the key objectives of the MedSeA Project was to engage society at large in the fight against ocean acidification through increased awareness, didactic and social activities and events, and dissemination of key data and results on socially and economically sensitive topics and fields. While the contribution of MedSeA to European and international research on ocean acidification has had a visible impact on the scientific knowledge now available to the scientific community on these topics; and while policy-oriented dissemination has made new key information available to the stakeholders in charge of defining the progress of climate-change and acidification policies, especially at the EU level, in the coming years, societal dissemination within the MedSeA Project has attempted, since the beginning, to address certain social categories that are sensibly affected by acidification and its effects but, at the same time, do not normally enjoy the same degree of involvement and participation in this kind of processes. Ocean acidification, in other words, goes beyond the biological and chemical elements that compose it as a scientific phenomenon. The implications of ocean acidification and warming — especially in a particular ecosystem and densely populated region such as the Mediterranean — systematically affect the social, cultural, and economic activities and practices of millions of people.

Significant parts of the MedSeA’s research work have been dedicated to the analysis of the socio-economic impact of ocean acidification. The sectors more sensibly and practically affected by these effects were fisheries, aquaculture, and leisure (water sports, diving, and tourism in a larger sense). MedSeA has actively engaged these interlocutors in its research work. The researchers expressly dealing with socio-economic implications managed to reach a number of categories that are directly involved in these industries and thereby affected by the complex implications of acidification. Over 400 scuba divers were successfully contacted and participated in surveys and questionnaires distributed within these affected groups to gather significant data on these impacts: the Medas and Cap de Reus areas of the Catalan Costa Brava were particularly cooperative, with the direct involvement of scuba diving associations and the spontaneous participation of frequent travellers and sport practitioners of the area. The repercussions of the project’s results and objectives attracted several public institutions of the region, especially tourism departments from coastal locations and authorities for local natural protected areas and parks. Similarly, seafood producers and harvesters as well as representatives from fisheries associations and unions engaged, individually and/or collectively, in the fieldwork developed by MedSeA researchers. In these sectors, MedSeA could count on the organisational help of the fisheries department of FAO and got in contact with a number of seafood/fisheries associations at the regional level in six countries: Spain, France, Italy, Tunisia, Montenegro, and Greece. The intermediation of collective associations was often essential to gain the trust and collaboration of individual producers as affected recipients of new knowledge and potential policy strategies. Not only were these first-hand contacts essential to guarantee the quality of the data collected within the project, but also inevitably converted into growing participation of these categories to raise awareness and spread crucial information among affected social and economic actors.

Finally, as MedSeA acknowledged since the beginning that the repercussions of ocean acidification go beyond economic and scientific interests, affecting the daily lives of citizens in the Mediterranean region and the balance of the Mediterranean ecosystems as we have known them so far, much effort was put into engaging actively layers of the population that would otherwise have scarce or incomplete access to this kind of information. Particular attention was paid to reaching a large public through dissemination via normal channels of communication — first and foremost, radio, television, and the press. By the end of the project, the media presence of MedSeA and its researchers counted on TV and radio interviews at local and national levels, as well as with widespread mentions of the project’s results in a number of newspapers and more sector-specific media, ranging from the New York Times to Spain’s El País, through La Vanguardia, Yahoo! News online, EuropaPress, Spanish national broadcaster RTVE, El Periódico, and a myriad local newspapers and publications that aimed directly at sparking the interest of local managers, administrators, policy-makers, and citizens. A promotional video, The other CO2 problem, was expressly produced for children and teens, in order to make them aware about such a complex issue with simple, concise and clear language, merging the effectiveness of the visual medium with the social sensitivity of the message. The MedSeA official video, Testing the Waters, was purposefully prepared with a b-roll version that could easily be distributed to newsreels and television specials, independent from language or nationality. All these means allowed MedSeA to reach the widest audience possible among those directly interested in or affected by ocean acidification and its complex, multiple impacts—fulfilling its ambition to also be a driver of cultural and social change and mobilise across Europe a conscious response to the challenges of ocean acidification.

List of Websites:
The MedSeA Project has established since its beginning a frequently-updated website with all basic information on the Project as well as references to the developments and results of MedSeA research work. The website was updated and managed by the Coordination Office of the MedSeA Project and is available at this link:

The Project Coordinator, Prof. Patrizia Ziveri (Universitat Autònoma de Barcelona) can be reached at this address:
The Project Coordination Office, in charge with project management, can be reached at this address: