International audienceThough the late Miocene “Messinian Salinity Crisis” has been intensely researched along the circum-Mediterranean basins, few studies have focused on the central part of the Mediterranean Basin and, especially, the pre-salt deposits. To improve our knowledge of the Messinian events, it is imperative to better understand this domain. In this study, we provide a more complete understanding of this central domain in the Provence Basin. We were able to recognize: a) thick marine detrital series (up to 1000 m) derived from the Messinian subaerial erosion which is partly prolongated in the distal part by b) a thick unit of deep marine deposits (up to 800 m) prior to the evaporites; c) a thick presumed alternation of detritals and evaporites (1500 m) below the mobile halite; and d) a two-step transgression at the end of the Messinian. Spatially, we document the eroded shelf to the deep basin (and from the western to the eastern parts of the Gulf of Lions), and temporally, we extend the interpretations from the early deposition of detritic sediments to the final sea-level rise. The results provide a new basis for discussion not only for the development of the Messinian Salinity Crisis but also for the reconstruction of the subsidence history of the Provence Basin

A detailed morphological analysis of the outer shelf and continental slope of the Western Gulf of Lion is presented, based on swath bathymetry data together with sub-bottom profiles and high resolution seismic reflection profiles. These data reveal two main erosive features, of very different dimensions: the axial incision and the canyon's major valley. The height of axial incisions' flanks with respect to the canyon deepest point (the thalweg) ranges from 40 to 150 m. It creates a small axial erosive path within the canyon's major valley, which is typically bounded by flanks of more than 700 m in height. We interpret the axial incision observed in the sea floor as the imprint of turbidity currents that eroded the floor of canyons during phases of connection to rivers (hyperpycnal turbidity current). Such currents are most likely to have formed during the Last Glacial Maximum (LGM) as both proximity of the shoreline (due to the lowstand of sea level) and high detrital sediment supply (due to glacial abrasion upstream) increased the flow of sediments delivered to the canyon heads. Fossil axial incisions, observed in seismic lines, are related to equivalent conditions. The axial incision, however, has a key influence on canyon evolution as it triggers mass wasting of different sizes that affect the canyon's major valley (head and flanks). We interpret the geometry of the canyon's major valley as the result of recurrent activity of axial incisions. These periods of activity occurred during low sea levels at glacial maxima and show a cyclicity of 100,000 years for the last 400,000 years

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Climate change is causing wide-ranging effects on ecosystem services critical to coastal communities and livelihoods, creating an urgent need to adapt. Most studies of climate change adaptation consist of narrative descriptions of individual cases or global synthesis, making it difficult to formulate and test locally rooted but generalizable hypotheses about adaptation processes. In contrast, researchers in this study analyzed key points in climate change adaptation derived from coordinated fieldwork in seven coastal communities around the world, including Arctic, temperate, and tropical areas on four continents. Study communities faced multiple challenges from sea level rise and warmer ocean temperatures, including coastal erosion, increasing salinity, and ecological changes. We analyzed how the communities adapted to climate effects and other co-occurring forces for change, focusing on most important changes to local livelihoods and societies, and barriers to and enablers of adaptation. Although many factors contributed to adaptation, communities with strong self-organized local institutions appeared better able to adapt without substantial loss of well-being than communities where these institutions were weak or absent. Key features of these institutions included setting and enforcing rules locally and communication across scales. Self-governing local institutions have been associated with sustainable management of natural resources. In our study communities, analogous institutions played a similar role to moderate adverse effects from climate-driven environmental change. The findings suggest that policies to strengthen, recognize, and accommodate local institutions could improve adaptation outcomes.