Climate change impact on the sea state conditions in the Mediterranean Sea under RCP and SSP emission scenarios

Abstract

The objective of the present study is to evaluate the recent past and future wave climate in the Mediterranean Sea considering the wave simulation results under Representative Concentration Pathways (RCPs) scenarios and also the latest greenhouse gas emission scenarios established by the Intergovernmental Panel on Climate Change's (IPCC) in its Sixth Assessment Report (AR6) and denoted as Shared Socio-economic Pathways (SSPs). Results covering two time periods for 30 years each are considered in the analysis and they comprise the recent past (1976–2005) and the mid-term future (2041–2070) under the RCP8.5 and SSP5-8.5 scenarios. For this purpose, the SWAN (Simulating WAves Nearshore) model is used to simulate the sea state conditions while to force the wave model, wind fields provided by three Regional Climate Models (RCMs) are considered. A multi-model ensemble (MME) is constructed based on the wave simulation results using RCMs from the fifth phase of the Coupled Model Intercomparison Project (CMIP5). Hindcast data simulated by SWAN using ERA5 wind fields are considered as reference and in order to evaluate the ability of the historical data to recreate the recent past sea state conditions normalized differences between these data are computed. Comparisons between the historical and mid-term future results are also performed to assess the dynamics of the sea state conditions in the Mediterranean Sea.