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Future extreme sea levels ( ESLs) and flood risk along European coasts will be strongly impacted by global warming. Yet, comprehensive projections of ESL that include mean sea level ( MSL), tides, waves, and storm surges do not exist. Here, we show changes in all components of ESLs until 2100 in view of climate change. We find that by the end of this century, the 100-year ESL along Europe's coastlines is on average projected to increase by 57 cm for Representative Concentration Pathways ( RCP)4.5 and 81 cm for RCP8.5. The North Sea region is projected to face the highest increase in ESLs, amounting to nearly 1 m under RCP8.5 by 2100, followed by the Baltic Sea and Atlantic coasts of the UK and Ireland. Relative sea level rise ( RSLR) is shown to be the main driver of the projected rise in ESL, with increasing dominance toward the end of the century and for the high-concentration pathway. Changes in storm surges and waves enhance the effects of RSLR along the majority of northern European coasts, locally with contributions up to 40%. In southern Europe, episodic extreme events tend to stay stable, except along the Portuguese coast and the Gulf of Cadiz where reductions in surge and wave extremes offset RSLR by 20-30%. By the end of this century, 5 million Europeans currently under threat of a 100-year ESL could be annually at risk from coastal flooding under high-end warming. The presented dataset is available through this link: . Plain Language Summary Future extreme sea levels and flood risk along European coasts will be strongly impacted by global warming. Here, we show changes in all acting components, i.e., sea level rise, tides, waves, and storm surges, until 2100 in view of climate change. We find that by the end of this century the 100-year event along Europe will on average increase between 57 and 81 cm. The North Sea region is projected to face the highest increase, amounting to nearly 1 m under a high emission scenario by 2100, followed by the Baltic Sea and Atlantic coasts of the UK and Ireland. Sea level rise is the main driver of the changes, but intensified climate extremes along most of northern Europe can have significant local effects. Little changes in climate extremes are shown along southern Europe, with the exception of a projected decrease along the Portuguese coast and the Gulf of Cadiz, offseting sea level rise by 20-30%. By the end of this century, 5 million Europeans currently under threat of a 100-year coastal flood event could be annually at risk from coastal flooding under high-end warming. [ABSTRACT FROM AUTHOR]

The increasing sea-level and meteorological changes associated with climate change increase the flood risk in coastal cities and low lying areas. Understanding the magnitude and impact of such changes is vital to design adaptive strategies and create awareness. Such risk predictions are possible with the use of hydrodynamic models that are coupled to climate models. In the context of the CoDEC project (Coastal Dataset for Evaluation of Climate impact), we compute the climate change induced changes on future sea-level, storm-surge, tides and waves, and the associated impacts on coastal flood risk for Europe from present date to 2100. We consider the 4.5 and 8.5 Representative Concentration Pathways (RCP), and produce extreme value statistics representing mid-century and end of century conditions. For the water levels, we use the Global Tide and Surge Model v3.0 (GTSMv3.0), a high resolution hydrodynamic model with global coverage. The model has a coastal resolution of 2.5km globally and 1.25km in Europe, and incorporates dynamically sea-level rise, tides and surge, and therefore calculates the non-linear interactions between them. For the meteorological forcing, we use the global EC-Earth climate model together with a European-wide high resolution climate model from the EURO-CORDEX archive. In order to assess the changes relative to present and past conditions, we perform a reanalysis of extreme sea levels using the newly available high resolution ERA5 forcing. Based on the relative changes, we design a number of indicators that provide useful information about the possible impacts of climate change globally. For Europe, a number of user cases are defined in which different industries use such indicators and global model outputs to downscale and assess impacts at a regional/local scale.We produce output for not only global coastlines at a high resolution, but also at predefined nesting points covering the global ocean which can be used for regional downscaling anywhere in the globe. [ABSTRACT FROM AUTHOR]