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Taking advantage of a large ensemble of Convection Permitting‐Regional Climate Models on a pan‐Alpine domain and of an object‐oriented dedicated analysis, this study aims to investigate future changes in high‐impact fall Mediterranean Heavy Precipitation Events at high warming levels. We identify a robust multi‐model agreement for an increased frequency from central Italy to the northern Balkans combined with a substantial extension of the affected areas, for a dominant influence of the driving Global Climate Models for projecting changes in the frequency, and for an increase in intensity, area, volume and severity over the French Mediterranean. However, large quantitative uncertainties persist despite the use of convection‐permitting models, with no clear agreement in frequency changes over southeastern France and a large range of plausible changes in events' properties, including for the most intense events. Model diversity and international coordination are still needed to provide policy‐relevant climate information regarding precipitation extremes. Plain Language Summary: Despite growing computational resources and multiple model developments, projecting future changes in the high‐impact Mediterranean Heavy Precipitation Events remains both a numerical and scientific challenge. The present study takes advantage of the recent availability of a relatively large ensemble of high resolution Regional Climate Models (2–3 km), which represent a step change in the simulation of precipitation extremes, and of an object‐oriented approach, allowing us to track the convective precipitating systems on an hourly basis. Looking at future changes in fall Mediterranean Heavy Precipitation Events at high warming levels, we identify a robust multi‐model agreement for an increased frequency from central Italy to the northern Balkans combined with a substantial expansion of the affected areas, and an increase in intensity, area, volume and severity over the French Mediterranean. However, considerable uncertainties remain in terms of frequency over parts of the domain arising from uncertainty in changes in large scale weather patterns, and in terms of degree of intensification for the most intense events. It suggests the need for model diversity and for more coordinated high resolution climate projections with careful selection of different driving global models in order to provide policy‐relevant climate information regarding precipitation extremes. Key Points: High‐resolution ensemble and object‐oriented approach offer a unique opportunity to study changes in Mediterranean extreme precipitationRobust agreement is found for an increase in intensity, volume and severity for future French Mediterranean Heavy Precipitation EventsEven at convection‐permitting scale, considerable uncertainty remains regarding the degree of intensification of the most extreme events [ABSTRACT FROM AUTHOR]

Large multiscenario multimodel ensembles (MMEs) of regional climate model (RCM) experiments driven by global climate models (GCMs) are made available worldwide and aim at providing robust estimates of climate changes and associated uncertainties. Due to many missing combinations of emission scenarios and climate models leading to sparse scenario–GCM–RCM matrices, these large ensembles, however, are very unbalanced, which makes uncertainty analyses impossible with standard approaches. In this paper, the uncertainty assessment is carried out by applying an advanced statistical approach, called QUALYPSO, to a very large ensemble of 87 EURO-CORDEX climate projections, the largest MME based on regional climate models ever produced in Europe. This analysis provides a detailed description of this MME, including (i) balanced estimates of mean changes for near-surface temperature and precipitation in Europe, (ii) the total uncertainty of projections and its partition as a function of time, and (iii) the list of the most important contributors to the model uncertainty. For changes in total precipitation and mean temperature in winter (DJF) and summer (JJA), the uncertainty due to RCMs can be as large as the uncertainty due to GCMs at the end of the century (2071–2099). Both uncertainty sources are mainly due to a small number of individual models clearly identified. Due to the highly unbalanced character of the MME, mean estimated changes can drastically differ from standard average estimates based on the raw ensemble of opportunity. For the RCP4.5 emission scenario in central–eastern Europe for instance, the difference between balanced and direct estimates is up to 0.8 ∘ C for summer temperature changes and up to 20 % for summer precipitation changes at the end of the century. [ABSTRACT FROM AUTHOR]

Large Multiscenarios Multimodel Ensembles (MMEs) of regional climate model (RCM) experiments driven by Global Climate Models (GCM) are made available worldwide, and aim at providing robust estimates of climate changes and associated uncertainties. Due to many missing combinations of emission scenarios and climate models leading to sparse Scenario-GCM-RCM matrices, these large ensembles are however very unbalanced, which makes uncertainty analyses impossible with standard approaches. In this paper, the uncertainty assessment is carried out by applying an advanced statistical approach, called QUALYPSO, to a very large ensemble of 87 EURO-CORDEX climate projections, the largest ensemble ever produced for regional projections in Europe. This analysis provides i) the most up-to-date and balanced estimates of mean changes for near-surface temperature and precipitation in Europe, ii) the total uncertainty of projections and its partition as a function of time, and iii) the list of the most important contributors to the model uncertainty. For changes of total precipitation and mean temperature in winter (DJF) and summer (JJA), the uncertainty due to RCMs can be as large as the uncertainty due to GCMs at the end of the century (2071-2099). Both uncertainty sources are mainly due to a small number of individual models clearly identified. Due to the highly unbalanced character of the MME, mean estimated changes can drastically differ from standard average estimates based on the raw ensemble of opportunity. For the RCP4.5 emission scenario in Central-Eastern Europe for instance, the difference between balanced and direct estimates are up to 0.8°C for summer temperature changes and up to 20% for summer precipitation changes at the end of the century. [ABSTRACT FROM AUTHOR]

Marine heatwaves (MHWs) are episodes of anomalous warming in the ocean, responsible for widespread impacts on marine ecosystems. For the first time summer MHW variability at surface and three ecosystem‐relevant depths of the upper Mediterranean Sea are assessed here for 1982–2017. We apply a MHW detection algorithm on a hindcast simulation, performed with a high‐resolution, fully coupled regional climate system model. Identified surface events last, on average, 15 days with a mean intensity of 0.6 °C above threshold and a maximum sea surface coverage of around 39%. Subsurface events are seasonally shifted and appear, on average, longer and more intense but less frequent and less extended in space than surface MHWs. We also find significant trends of increase in most MHW properties throughout the period, with severe surface MHWs detected for the first time in 2012, 2015, and 2017. However, MHW spatial ≪ hot spots ≫ are inhomogeneously distributed in surface and deeper layers. Plain Language Summary: Marine heatwaves (MHWs) are episodes of prolonged and extended anomalous warming in the ocean, responsible for widespread impacts on marine ecosystems and related fisheries. Here, we identify for the first time all the MHWs that have occurred at surface and three ecosystem‐relevant depths of the Mediterranean Sea between 1982 and 2017. To do this, we use the output from the latest version of a regional, high‐resolution climate system model and a consistent detection framework. We find that past surface events, on average, last around 2 weeks and cover almost half the basin with above‐normal temperatures by more than half a degree. Subsurface events appear seasonally shifted and on average, longer and more intense but less frequent and less extended in space than surface MHWs. Following an increase of extremes temperatures with time, surface MHWs appear to have become longer, more severe and spatially extended, while record‐breaking MHWs are identified for the first time in 2012, 2015, and 2017 in addition to the well‐documented 2003 event. However, spatial distribution of MHW ≪ hot spots ≫ differs at surface and depth. Key Points: First time significant past trends of (sub)surface Mediterranean Marine heatwave characteristics are detected using a consistent frameworkSubsurface events are seasonally shifted and on average longer and more severe than surface ones with different spatial hot spotsRecord‐breaking events are identified for the first time in 2012 and 2015 using a high‐resolution coupled regional climate system model [ABSTRACT FROM AUTHOR]

Abstract: Chaotic intrinsic variability is a fundamental driver of the oceanic variability. Its understanding is key to interpret observations, evaluate numerical models, and predict the future ocean and climate. Here we study intrinsic variability of deep convection in the northwestern Mediterranean Sea using an ensemble eddy‐resolving hindcast simulation over the period 1979–2013. We find that the variability of deep convection is mostly forced but also, to a considerable extent, intrinsic. The intrinsic variability can dominate the total convection variability locally and over a single winter. It also makes up a significant fraction of its interannual variability but has only modest impacts on the long‐term mean state. We find that the occurrence of deep convection is random 18% of years at the basin scale, and 29% locally at the LION observational site. Spatially, the intrinsic variability is highest far from the continental shelf. We relate this pattern to baroclinic instability theory that takes bottom stabilization into account. [ABSTRACT FROM AUTHOR]

Croatian Adriatic coast is often affected by extreme precipitation that leads to flash-floods with severe damage, both human and material. The added value of high-resolution regional climate model (RCM) simulations of mean and extreme precipitation has already been proven, but RCMs' skill over complex terrain, such as coastal mountains in Croatia, still poses some challenges and open questions. We evaluate the daily precipitation simulations of high-resolution (0.11°) RCM ALADIN-Climate versions 5.2 (ALD5) and 6.3 (ALD6) driven by the ERA-Interim reanalysis over the Med-CORDEX domain. The spectral nudging technique (SN) was applied on both model versions (AD5SN, ALD6SN). Reference datasets used are precipitation analysis system MESCAN, available on 5.5 km resolution every 6 h, and 24 h accumulated precipitation data from the Croatian raingauge network. To assess the agreement between model and reference we perform statistical analysis in terms of multi year spatial bias for the mean annual and seasonal precipitation, the number of wet days, the 99.9th quantile, and the quantile-quantile plots for the period 1979-2012. ALD6SN outperforms the previous versions by diminishing the drizzling effect, with notably less wet days than ALD5 and ALD5SN, and with significantly improved lower precipitation quantiles. All model versions show an underestimation of higher-order quantiles. The spectral nudging in ALD5SN causes an overestimation of the lower quantiles, with minimum difference in higher quantiles compared to ALD5. [ABSTRACT FROM AUTHOR]

The Mediterranean region of France are regularly affected by extreme precipitation that often lead to devastating flash-floods, often associated with both human and material damages. The evolution of such events in terms of occurrence and severity with climate change remains an open question.The purpose of the current study is to characterize the future evolution of these heavy precipitating events in terms of occurrence and intensity. A historical simulation (1976 – 2005) will be compare to a future simulation (2071 – 2100) for the RCP8,5 scenario. The CNRM-CM5 global climate is used as driver model. The study also compare climate change simulations from a convection parametrized convection model (ALADIN-Climate) and a convection permitting reginal climate model (AROME-Climate). These simulations were carried out on the domain defined by the CORDEX Flagship Pilot Study "Convective phenomena at high resolution over Europe and the Mediterranean". It is centered on the Alps. This domain allows a good representation of the large scale circulation over the Mediterranean sea that causes convective phenomena in the Southeastern France. The study of changes in spatial distribution and cumulative precipitation will be based on daily and hourly averages and quantiles of precipitation.I would like to share my knowledge on convection permitting regional climate model with interested people. This workshop would be a great opportunity and I hope, I will have the opportunity to exchange with people from this community. [ABSTRACT FROM AUTHOR]

The evolution of different renewable energy resources under different climate change scenarios is a key factor for the energy industry and for the energy transition. The possible changes with respect to present conditions for the operating plants and the projected resources can affect the financial frame and viability of the projects.Over Europe, climate models give a robust answer in terms of global warming and other important climate variables. However, GCMs and RCMs disagree in the projected changes of surface solar radiation (SSR) over Europe. Whereas global climate models, GCMs, present a clear positive signal for the end of XXI century, some studies show a negative anomaly for the same period in RCMs from EURO-CORDEX ensemble. This discrepancy is of special interest for photovoltaic (PV) power plants, whose resource is precisely solar radiation reaching earth's surface.In this work, which is a contribution to the CORDEX FPS-aerosols, we try to explain the reasons of the difference in anomalies focusing on the representation of aerosols in the scenario simulations of RCMs. We use regional climate models simulations from the EURO-CORDEX ensemble grouped together by its forcing GCM. Different families of runs are analysed with only one simulation with evolving aerosols per group. We focus on RCP8.5 emissions scenario. In addition, a detailed PV model is used to estimate future PV potential over Europe, which has not been considered in previous approaches.Results of this study will lead to the obtention of more accurate PV projections over Europe, demanded by policymakers and the energy sector. [ABSTRACT FROM AUTHOR]

Climate simulations made with two regional climate models (RCMs), the French Aire Limitée Adaptation Dynamique Développement International (ALADIN) and the Canadian Regional Climate Model, version 5 (CRCM5), operating on 10-km meshes for the period 1989-2011, and the Hydro-Québec hydrological model (HSAMI), are used to reconstruct the spring 2011 Richelieu River flood in the southern region of the province of Québec, Canada. The analysis shows that the simulated fields of 2-m air temperature, precipitation, and snow water equivalent by the RCMs closely match the observations with similar multiyear means and a high correlation of the monthly anomalies. The climatic conditions responsible for the 2011 flood are generally well simulated by the RCMs. The use of multidecadal RCM simulations facilitates the identification of anomalies that contributed to the flood. The flood was linked to a combination of factors: the 2010/11 winter was cold and snowy, the snowmelt in spring was fast, and there was a record amount of precipitation in April and May. Driven by outputs from the RCMs, HSAMI was able to reproduce the mean hydrograph of the Richelieu River, but it underestimated the peak of the 2011 flood. HSAMI adequately computes the water transport from the mountains to the river mouth and the storage effect of Lake Champlain, which dampens the flood over a long period. Overall, the results suggest that RCM simulations can be useful for reconstructing high-resolution climate information and providing new variables that can help better understand the causes of extreme climatic events. [ABSTRACT FROM AUTHOR]

Aim To study the combined effects of climate change on connectivity between marine protected areas ( MPAs) and larval supply to the continental shelf. Location The Mediterranean Sea, where sea surface temperatures are expected to strongly increase by the end of the 21st century, represents an archetypal situation with a dense MPA network but resource overexploitation outside. Methods Using an individual-based mechanistic model of larval transport, forced with an emission-driven regional climate change scenario for the Mediterranean Sea, we explored the combined effects of changes in hydrodynamics, adult reproductive timing and larval dispersal on the connectivity among MPAs and their ability to seed fished areas with larvae. Results We show that, over the period 1970-2099, larval dispersal distances would decrease by 10%, the continental shelf area seeded with larvae would decrease by 3% and the larval retention fraction would increase by 5%, resulting in higher concentration of larvae in smaller areas of the continental shelf. However, connectance within the MPA network would increase by 5% as more northern MPAs would become suitable for reproduction with increasing temperatures. We also show that the effects of changes in adult reproductive timing and larval dispersal on connectivity patterns are additive. Main conclusions Climate change will influence connectivity and the effectiveness of MPA networks, and should receive more attention in future conservation planning and large-scale population dynamics. [ABSTRACT FROM AUTHOR]

Spectral nudging, a dynamic downscaling method, has been used as a suitable approach to force a regional model to adopt prescribed large-scales over the entire domain, not just at the lateral boundaries, while developing realistic detailed regional features consistent with the large-scales. The aim of this study is to compare a global spectral climate model at high resolution (50 km) and a driven spectral regional climate model over Europe by using the so-called perfect model approach. The spectral nudging method is applied in order to achieve a better representation of large-scale climate over a limited domain. The results show that the regional model driven only at its lateral boundaries presents a summer warm bias in the middle of the domain. This bias disappears when spectral nudging is applied. On the other hand, the smallest scales which are not driven by the spectral nudging are not significantly affected by scale interaction. The only detrimental impact of spectral nudging is a slight precipitation increase in the upper quantiles of precipitation, which can be resolved by large-scale nudging of specific humidity. [ABSTRACT FROM AUTHOR]

Abstract: For more than five decades, the Mediterranean Sea has been identified as a region of so‐called thermohaline circulation, namely, of basin‐scale overturning driven by surface heat and freshwater exchanges. The commonly accepted view is that of an interaction of zonal and meridional conveyor belts that sink at intermediate or deep convection sites. However, the connection between convection and sinking in the overturning circulation remains unclear. Here we use a multidecadal eddy‐permitting numerical simulation and glider transport measurements to diagnose the location and physical drivers of this sinking. We find that most of the net sinking occurs within 50 km of the boundary, away from open sea convection sites. Vorticity dynamics provides the physical rationale for this sinking near topography: only dissipation at the boundary is able to balance the vortex stretching induced by any net sinking, which is hence prevented in the open ocean. These findings corroborate previous idealized studies and conceptually replace the historical offshore conveyor belts by boundary sinking rings. They challenge the respective roles of convection and sinking in shaping the oceanic overturning circulation and confirm the key role of boundary currents in ventilating the interior ocean. [ABSTRACT FROM AUTHOR]

We investigate European regional climate change for time periods when the global mean temperature has increased by 1.5 and 2 °C compared to pre-industrial conditions. Results are based on regional downscaling of transient climate change simulations for the 21st century with global climate models (GCMs) from the fifth-phase Coupled Model Intercomparison Project (CMIP5). We use an ensemble of EURO-CORDEX highresolution regional climate model (RCM) simulations undertaken at a computational grid of 12.5 km horizontal resolution covering Europe. The ensemble consists of a range of RCMs that have been used for downscaling different GCMs under the RCP8.5 forcing scenario. The results indicate considerable near-surface warming already at the lower 1.5 °C of warming. Regional warming exceeds that of the global mean in most parts of Europe, being the strongest in the northernmost parts of Europe in winter and in the southernmost parts of Europe together with parts of Scandinavia in summer. Changes in precipitation, which are less robust than the ones in temperature, include increases in the north and decreases in the south with a borderline that migrates from a northerly position in summer to a southerly one in winter. Some of these changes are already seen at 1.5 °C of warming but are larger and more robust at 2 °C. Changes in near-surface wind speed are associated with a large spread among individual ensemble members at both warming levels. Relatively large areas over the North Atlantic and some parts of the continent show decreasing wind speed while some ocean areas in the far north show increasing wind speed. The changes in temperature, precipitation and wind speed are shown to be modified by changes in mean sea level pressure, indicating a strong relationship with the large-scale circulation and its internal variability on decade-long timescales. By comparing to a larger ensemble of CMIP5 GCMs we find that the RCMs can alter the results, leading either to attenuation or amplification of the climate change signal in the underlying GCMs. We find that the RCMs tend to produce less warming and more precipitation (or less drying) in many areas in both winter and summer. [ABSTRACT FROM AUTHOR]

We investigate European regional climate change for time periods when the global mean temperature has increased by respectively 1.5 °C and 2 °C compared to preindustrial conditions. Results are based on regional downscaling of transient climate change simulations for the 21st century with global climate models (GCMs) from the fifth phase Coupled Model Intercomparison Project (CMIP5). We use an ensemble of EURO-CORDEX high-resolution regional climate model (RCM) simulations undertaken at a computational grid of 12.5 km horizontal resolution covering Europe. The ensemble consists of a range of RCMs that have been used for downscaling different GCMs under different forcing scenarios. The results indicate considerable near-surface warming already at the lower 1.5 °C warming. Regional warming exceeds that of the global mean in most parts of Europe, strongest in northernmost parts of Europe in winter and in southernmost parts of Europe together with parts of Scandinavia in summer. Changes in precipitation, that are less robust than the ones in temperature, include increases in the north and decreases in the south with a borderline that migrates from a northerly position in summer to a southerly one in winter. Some of these changes are seen already at 1.5 °C warming but larger and more robust at 2 °C. Changes in near-surface wind speed are associated with a large spread between individual ensemble members at both warming levels. Relatively large areas over the North Atlantic and some parts of the continent shows decreasing wind speed while some ocean areas in the far north show increasing wind speed. The changes in temperature, precipitation and wind speed are shown to be modified by changes in mean sea level pressure indicating a strong relationship with the large-scale circulation and its internal variability on decade-long timescales. By comparing to a larger ensemble of CMIP5 GCMs we find that the RCMs can alter the results leading either to attenuation of amplification of the climate change signal in the underlying GCMs. We find that the RCMs tend to produce less warming and more precipitation (or less drying) in many areas in both winter and summer. [ABSTRACT FROM AUTHOR]

Aim In this paper, we applied the concept of 'hierarchical filters' in community ecology to model marine species distribution at nested spatial scales. Location Global, Mediterranean Sea and the Gulf of Gabes ( Tunisia). Methods We combined the predictions of bioclimatic envelope models ( BEMs) and habitat models to assess the current distribution of 20 exploited marine species in the Gulf of Gabes. BEMs were first built at a global extent to account for the full range of climatic conditions encountered by a given species. Habitat models were then built using fine-grained habitat variables at the scale of the Gulf of Gabes. We also used this hierarchical filtering approach to project the future distribution of these species under both climate change (the A2 scenario implemented with the Mediterranean climatic model NEMOMED8) and habitat loss (the loss of Posidonia oceanica meadows) scenarios. Results The hierarchical filtering approach predicted current species geographical ranges to be on average 56% smaller than those predicted using the BEMs alone. This pattern was also observed under the climate change scenario. Combining the habitat loss and climate change scenarios indicated that the magnitude of range shifts due to climate change was larger than from the loss of P. oceanica meadows. Main conclusions Our findings emphasize that BEMs may overestimate current and future ranges of marine species if species-habitat relationships are not also considered. A hierarchical filtering approach that accounts for fine-grained habitat variables limits the uncertainty associated with model-based recommendations, thus ensuring their outputs remain applicable within the context of marine resource management. [ABSTRACT FROM AUTHOR]

Atmospheric circulation patterns that are conducive to extreme ocean heat loss are investigated at four sites of special interest in the Mediterranean Sea. The Gulf of Lions, the South Adriatic Sea, the Cretan Sea, and the Levantine Sea are areas where anomalously high winter heat loss may lead to deep- or intermediate-water formation. At each of the above sites, the atmospheric circulation during such events is derived by averaging the sea level pressure (SLP) fields during the lower decile of the wintertime series of the net heat exchange. A relatively simple SLP pattern dominated by an anticyclone over northwestern Europe with a weaker cyclone to the southeast is found to be associated with strong heat loss in the selected sites with minor variations in pattern structure depending on the site. The SLP composite pattern reflects the combined effect of different atmospheric modes of variability and the authors consider the impacts on heat loss of a number of these modes (North Atlantic Oscillation, east Atlantic pattern, east Atlantic-west Russia pattern, and Scandinavian pattern), together with the North Sea-Caspian pattern and the Mediterranean index. The extremes in heat loss are strongly connected with the intensity and the positions of the poles of these patterns that modulate, through the necessary SLP gradient and associated northerlies, the transfer of cold and dry air over the areas of dense-water formation. Analysis of air-sea temperature difference, specific humidity, and evaporation anomalies indicates that the extremes of the net heat fluxes are primarily due to the latent and sensible heat flux components. [ABSTRACT FROM AUTHOR]

ABSTRACT We assess the impact of two sources of uncertainties in a limited area model (LAM) on the representation of intense precipitation: the size of the domain of integration and the use of the spectral nudging technique (driving of the large-scale within the domain of integration). We work in a perfect-model approach where the LAM is driven by a general circulation model (GCM) run at the same resolution and sharing the same physics and dynamics as the LAM. A set of three 50 km resolution simulations run over Western Europe with the LAM ALADIN-Climate and the GCM ARPEGE-Climate are performed to address this issue. Results are consistent with previous studies regarding the seasonal-mean fields. Furthermore, they show that neither the use of the spectral nudging nor the choice of a small domain are detrimental to the modelling of heavy precipitation in the present experiment. [ABSTRACT FROM AUTHOR]

Two climate simulations of 150 years, performed with a coupled ocean/sea-ice/atmosphere model including stratospheric ozone, respectively with and without heterogeneous chemistry, simulate the tropospheric warming associated with an increase of the greenhouse effect of carbon dioxide and other trace gases since 1950 and their impact on sea–ice extent, as well as the stratospheric cooling and its impact on ozone concentration. The scenario with heterogeneous chemistry reproduces the formation of the ozone hole over the South Pole from the 1970s and its deepening until the present time, and shows that the ozone hole should progressively fill during the coming decades. To cite this article: J.-F. Royer et al., C. R. Geoscience 334 (2002) 147–154. [Copyright &y& Elsevier]

Aerosols are known to interact with shortwave and longwave radiation, provoking a negative radiative forcing at the surface with ensuing cooling. They have therefore an important role in the Mediterranean climate system. In order to estimate the impact of aerosols on future climate, we use the ALADIN-Climat regional climate model which incorporates a prognostic aerosol scheme (TACTIC). It includes desert dust, sea salt, organic, black carbon, sulphate, ammonium and nitrate particles (Drugé et al., ACPD, 2018). The aim of this work is to study the future evolution of the different aerosols over the Euro-Mediterranean area, as well as the future climate sensitivity of this region to anthropogenic/natural aerosols. We realised a historical simulation (1971-2000) and two CMIP6 scenarios (SSP 5-8.5; 2021-2050), one using evolutive aerosols and the other constant anthropogenic emissions. This protocol allows us to identify the role of aerosols in the scenarios. First results show an additional increase in surface radiation and temperature over the future period due to aerosols, more precisely due to the drop in anthropogenic (notably sulfate) emissions. The future evolution of aerosols has also consequences on atmospheric circulation, precipitations and cloud cover that will be discussed in this presentation. [ABSTRACT FROM AUTHOR]

For more than five decades, the Mediterranean Sea has been identified as a region of so-called thermohaline circulation, namely of basin-scale overturning driven by surface heat and freshwater exchanges. The commonly accepted view is that of an interaction of zonal and meridional "conveyor belts" that sink at intermediate or deep convection sites. However, the connection between convection and sinking in the overturning circulation remains unclear. Here we use multi-decadal physical and biogeochemical simulations of the Mediterranean Sea and glider transport measurements to diagnose the location and physical drivers of this sinking. We find that most of the net sinking occurs within 50km of the boundary, away from open-sea convection sites. We also diagnose significant vertical biogeochemical fluxes near the boundary associated with this downwelling. We relate this sinking near the boundary to vorticity dynamic and the role of the Earth's rotation in suppressing net vertical motions in the open ocean. These findings corroborate previous idealized studies and conceptually replace the historical offshore "conveyor belts" by boundary "sinking rings". They challenge the respective roles of convection and sinking in shaping the oceanic overturning circulation and confirm the key role of boundary currents in ventilating the interior ocean. [ABSTRACT FROM AUTHOR]

The FishMed database provides traits, phylogeny, current and projected species distribution of Mediterranean fishes, and associated sea surface temperature (SST) from the regional oceanic model NEMOMED8. Data for the current geographical distributions of 635 Mediterranean fish species were compiled from a published expert knowledge atlas of fishes of the northern Atlantic and the Mediterranean (FNAM) edited between 1984 and 1986 and from an updated exotic fish species list. Two future sets of projected species distributions were obtained for the middle and end of the 21st century by using an ensemble forecasting approach for 288 coastal Mediterranean fish species based on SST according to the IPPC/SRES A2 scenario implemented with the Mediterranean climatic model NEMOMED8. The functional part of the database encompasses 12 biological and ecological traits (maximal and common lengths, vertical distribution, habitat, migration type, mode of reproduction, sex shift, semelparity, diet type (larvae and adults), social behavior, species origin, and depth) for the 635 fish species. To build the phylogeny we inferred the timing and geographic origins of Mediterranean teleost species diversity using nucleotide sequences collected from GenBank including 62% ofMediterranean teleost species plus nine outgroups. Maximum likelihood Bayesian phylogenetic and dating analyses were calibrated using 20 fossil species. An additional 124 fish species were grafted onto the chronogram according to their taxonomic affinity to obtain a phylogenetic tree including 498 species. Finally we also present the associated SST data for the observed period (1961-1980) and for themiddle (2040-2059) and the end of the 21st century (2080-2099) obtained fromNEMOMED8 according to the IPCC A2 scenario. The FishMed database might be of interest in the context of global anthropogenic changes as coastal Mediterranean ecosystems are currently recognized as one of the most impacted ecosystems on earth. [ABSTRACT FROM AUTHOR]