Shelf sea dynamics and storm surges

Quantitative projections of future coastal sea level changes and an accurate assessment of socioeconomic impacts of high-end sea level and extreme events demand to improve our detailed understanding of the imprint of all those effects on local sea level. Extreme events often induce damaging morphodynamic changes and coastal erosion. Essential for the use of sea level information as part of coastal management is the availability of likelihood information and uncertainty measures. For this purpose, we need to propagate the full error information and probability density functions from the global scale or remote location to any coastal locations together with sea level information itself, be they caused by ocean and climate dynamics, residing in the solid Earth, or originating from the cryosphere and hydrology. However, estimates from existing climate model projections (CMIP5) suffer dramatically from the lack of all processes involved. This includes the lack of spatial resolution of the ocean model components required to simulate shelf sea and coastal processes (1°-2°, vs. 1/10° and better required for regional and coastal simulations), but also the lack of pertinent physics, including coastal and shelf sea dynamics. Consequently, sophisticated regional downscaling efforts of the largescale climate sea level signals are required to assess vulnerability and potential resilience capacities. In addition, local water withdrawal and/or land use change also affect local relative sea level change.

Already Denbo and Allen (1987) have shown that the characteristics of the large scale response of coastal sea level to fluctuations in wind stress can be very variable with latitude and in time, revealing the influence of many coastal dynamical details. More recently, Dangendorf et al. (2013) investigated sea level trends derived from the North Sea, North Atlantic and Mediterranean Sea tide gauges and showed that regional and local atmospheric forcing is partly responsible for the observed regional patterns of sea level change and to some extent also to regionally dependent acceleration in sea-level rise during the 1990s. Along the western European coast, tide gauge records show significant decadal variability (up to 15 cm) and a high correlation with the NAO and among themselves at decadal periods (Calafat et al., 2012). Boundary waves may propagate thousands of kilometers poleward and raise sea levels also in the North Sea (Dangendorf et al., 2014). The baroclinic nature of these signals provides important information about required horizontal resolution (<20km) of downscaling experiments. Similar contributions from all relevant climate modes, e.g. in South-East Asia originating from ENSO, PDO, SAM, of IODM, need to be quantified for our study regions, for which alongshore wind and wave propagation could be major contributors to coastal sea level variability.

Human dimensions of sea level change

Sea level rise is threatening coastal societies with a large range of socio-economic consequences. This includes a reduction or loss of vital coastal ecosystem services such as ...

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Recent and future large-scale sea level changes

Since the end of the 19th century, global mean sea level is estimated to have risen by about 20 cm, and the rise appears to have accelerated during the past two decades ...

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Ocean – ice sheet interaction

The interface between oceans and ice sheets plays an important role in the future melting of ice sheets. However, the processes occurring at this interface are only poorly understood and ...

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Solid Earth sea level change contributions

For quantitative projections of regional sea level change we need to quantify factors arising from the visco-elastic response of the solid Earth to ice/water mass redistributions ...

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Shelf sea dynamics and storm surges

Quantitative projections of future coastal sea level changes and an accurate assessment of socioeconomic impacts of high-end sea level and extreme events demand to improve ...

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Scientific Objectives

As its central scientific objective, SeaLevel aims to perform an integrated analysis of climaterelated sea level change and associated coastal human-environment interactions with a focus on two study regions ...

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