The dataset presents extreme-value, return period, and percentile indicators for coastal sea levels in a European-wide domain. The indicators are computed from tidal dynamics, storm surge and sea level rise data based upon past observational data and future climate projections. This dataset provides an understanding of the European coastal hydrodynamics under the impact of climate change. It provides added value for various coastal sectors and studies such as port, shipping, and coastal management.
To compute these indicators, the Deltares Global Tide and Surge Model (GTSM) version 3.0 is used together with regional climate forcing and sea level rise initial conditions. The regional climate forcing employed is the HIRHAM5 model from the Danish Meteorological Institute (DMI), a member of the EURO-CORDEX climate model ensemble, which is downscaled from the global climate model EC-EARTH. By using a regional climate model and a high-resolution forcing field, GTSM is able to produce a more consistent and high quality dataset. In order to assess the impact of climate change, the GTSM model is run for three different climate scenarios: the present climate (labelled 'historical'), and two Representative Concentration Pathway (RCP) scenarios that correspond to an optimistic emission scenario where emissions start declining beyond 2040 (RCP4.5) and a pessimistic scenario where emissions continue to rise throughout the century often called the business-as-usual scenario (RCP8.5). Given that the projections of these climate scenarios are based on a single combination of the regional and global climate models, users of these data should take in consideration that there is an inevitable underestimation of the uncertainty associated with this dataset. In addition to the climate scenarios, a reanalysis dataset is computed by forcing GTSM with ERA5 reanalysis. This provides recent historical water-levels that can be used to look at specific (extreme) events in the past.
It is now available for download from https://cds.climate.copernicus.eu/cdsapp#!/dataset/sis-water-level-change-indicators?tab=overview
This dataset was produced on behalf of the Copernicus Climate Change Service for the SIS European Coasts contract.
