Scientific Basis

Coastal sea level rise is one of the key effects of anthropogenic global warming, with far-reaching consequences for all coastal societies around the world (Milne et al., 2009). The level and severity of related societal impacts on low-lying coastal regions and islands will fundamentally depend on the detailed amount and the rate of coastal sea level change, on the availability of predictions accompanied by uncertainty information, on the natural response of the surrounding coastal system to those changes, but also on the way societies choose to adapt to sea level change - technically, economically and politically. Many of the respective considerations inevitably have to be local in nature, involving sustainable coastal development, integrated coastal management, coastal protection, damages, economic slowdown, changes in biodiversity, and health issues. Social sciences aspects of sea level research therefore have to be approached in a very local way, e.g., due to available scientific information, resources, economic power, and the level of local governance. However, local sea level change fundamentally depends on processes taking place remotely, making coastal sea level studies inevitably a global problem. Moreover, local societal impacts of sea level change can advance to global dimensions (e.g., trading and migration).

Local sea level is directly or indirectly affected by all components of the climate system, including the ocean, atmosphere, cryosphere, solid Earth and terrestrial hydrology (Fig. 1), but also by local human interventions (e.g. Becker et al., 2009). However, the relative contribution of individual processes to regional or local sea level change strongly depends on the spatial and temporal scales under consideration. Besides climate processes, local vertical movement of the sea floor can likewise influence coastal sea level in a severe way (e.g. Nicholls and Cazenave, 2010), and requires addressing geological processes (e.g., tectonics, isostatic adjustment, geomorphology), but also human activities such as ground-water extraction.

Fig. 1: Processes influencing regional sea level (besides global mean sea level change) are associated with: dynamical variations of the ocean circulation; a static response to atmospheric pressure changes; mass variations in the Earth system, notably an isostatic adjustment of the Earth’s crust to past and present loadings; changes in polar ice masses; and changes in continental water storage. Local changes are also affected by vertical motion of the sea floor due to earthquakes, subsidence, or anthropogenic influences, such as ground water withdrawal (after Stammer et al., 2013).

Significant progress in understanding trends in global mean sea level has been achieved over the last decade (Church et al., 2011). However, fundamental gaps remain in our quantitative understanding of processes leading to coastal sea level changes in the past, in our ability to project coastal changes into the future (Church et al., 2014) and in our ability to use this information for guidance of the coastal community. A dedicated scientific program is required that identifies and quantifies processes leading to coastal sea level change, and that provides comprehensive information on the interactions of socioeconomic developments with geophysical processes and climate modes, related societal responses, resilience capacities, and preparedness for undertaking adaptation measures, schematically illustrated on the title page graphic. Only such a program jointly involving scientist from the climate and coastal research communities can provide the scientific basis for a well-founded investigation of adaptation strategies to sea level change.

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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