Society adaptation for coping with mountain risks in the climate change context
Résumé
Mountains represent an important part of the global earth system. Because of their vertical extent, climate varies drastically with elevation and thus differs from those in adjacent lowland areas. Natural processes controlled by hydro-meteorological triggers (e.g. floods, landslides, rockfalls) will add further environmental pressures on both social and natural systems, stressing the need to promptly conduct proactive adaptation plans. The relevance of mountain hazard and risk zonation for environmental policy and decision making is set forth in the European Thematic Strategy for Soil Protection and the associated proposal of a Framework Directive, in which hydro-meteorological hazards are considered as one of the soil threats for which it is necessary to identify risk areas where risk reduction measures have to be implemented. However, to implement risk mitigation strategies in an integrated way
(e.g. including physical but also economic and social adaptation), additional research is needed on how climate controls mountain hazards occurrence. The influence of climate and climate change on slope stability and floods over various spatial and temporal scales has to be better understood and quantified; studies are also needed on how the main economic, social and political stakeholders interact for the definition of adaptation scenarios at the region scale.
The SAMCO (Society Adaptation for coping with Mountain risks in a global change Context) project aims to develop a proactive resilience framework enhancing the overall resilience of societies on the impacts of mountain risks. The project aims to elaborate methodological tools to characterize and measure ecosystem and societal resilience from an operative perspective on three mountain representative case studies.
To achieve this objective, the methodology is split in several points with (1) the definition of the potential impacts of global environmental changes (climate system, ecosystem e.g. land use, socio-economic system) on landslide hazards, (2) the analysis of these consequences in terms of vulnerability (e.g. changes in the location and characteristics of the impacted areas and level of their perturbation) and (3) the implementation of a methodology for quantitatively investigating and mapping indicators of mountain slope vulnerability exposed to several hazard types, and the development of a GIS-based demonstration platform.
The strength and originality of the SAMCO project is to combine different techniques, methodologies and models (multi-hazard assessment, risk evolution in time, vulnerability functional analysis, and governance strategies) and to gather various interdisciplinary expertises in earth sciences, environmental sciences, and social sciences.
The climate change inputs of the project correspond to at least 2 scenarios of emission of greenhouse gases. The used simulations available on the portal DRIAS (http://www.drias-climat.fr) were performed with the GHG emissions scenarios (RCP: Representative concentration pathways, according to the standards defined by the GIEC) RCP 2.8, RCP 4.5 and RCP 8.5 for the ALADIN-Climate model of Météo-France, and RCP 4.5 and RCP 8.5 for the WRF model used by the IPSL. The impact of climate change is then firstly addressed through the use of these climate scenarios into hazards computations. In that way, future changes in temperature and precipitation volume and patterns are analyzed, permitting to address the direct and indirect impacts of climatic change on mountain societies and their vulnerability to change.
Secondly, the climate change is also considered in global scenarios, with taking into account political actions at local and global scale that might influence the climate change as well as the land use planning in the areas of interest. It is then possible to identify the most important factors of community resilience (e.g. coping capacity) and their dependence upon controlling factors in order to propose risk management strategies adapted to possible impacts of global changes.