Report on scenarios for the Mediterranean Sea

The SEACOAST project of the Water Resources Unit (H01) of the Institute of Environment and Sustainability (IES) has aimed during 2015 to monitor, model and assess the environmental status of the marine and coastal waters of European seas. The SEACOAST project assists in implementing the objectives of the Marine Strategy Framework Directive (MSFD) by the assessment of the marine environment through targeted modelling and monitoring activities. Specifically, the main objective of the modelling activities within SEACOAST 2015 has been to assess the anthropogenic and climate driven changes on the marine environment by using adequate numerical modelling tools that include the main components of the Earth System; atmosphere, ocean, land and anthroposphere. In the scientific jargon, an integrated modelling system of this nature is typically referred as a Regional Earth System Model (RESM). In this context, the marine modelling group has been working to develop such modelling system for the Mediterranean Sea as a 'benchmark' case of EU regional seas. Within Deliverable 6 of SEACOAST 2015 on scenarios of the Mediterranean Sea, we have used a regional climate model (RCM) developed within the EuroCORDEX initiative to obtain atmospheric conditions for the Mediterranean region for the 21st century. However, before using the RCM variables to force the ocean model an intense work was necessary to reduce the bias in surface properties induced by model deficiencies. Once the present-day conditions in the basin could be satisfactorily simulated by using the RCM variables, this coupled atmosphere/ocean/hydrology system has been used to create a set of scenario simulations into the future under various emission scenarios (business as usual and worst case) and considering different options for freshwater management (associated with socio-economic scenarios). The objective of this work during 2015 has been to create the model system and to test its capability to perform in scenario mode for the Mediterranean Sea. Now that the tool is created and tested, it could be used to explore consequences of different policy options for Europe in near future in combination with expected climatic changes in the context of the MSFD.