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 (Glacial Isostatic Adjustment - GIA), ongoing land ice discharge, changes of land water storage and river runoff and the regional evolution of coastal morphology due to sedimentary transport processes. Corresponding deformations of ocean basins and gravitational changes from these factors produce regional changes in sea level that fundamentally affect remote coastlines. However, in existing climate projections, only preliminary attempts have been made to account for those effects (Slangen et al., 2014), although they are expected to become stronger in their spatial pattern than observed in present day internal sea level variability (see Fig. 2c). It was only recently hypothesized that the effects of viscoelastic deformations of the Earth’s lithosphere on regional sea level could be of particular importance for the reconstruction of paleo-sea level distributions, but also for projections of future sea level change in response to natural and anthropogenic changes in the distribution of water between land and ocean.

In certain areas of the ocean, the steric nature of regional sea level change is superseded by massrelated effects. The separation between both effects is an important step in detecting anthropogenic effects on sea level. Apart from the steric adjustments associated with changes in the thermohaline circulation and atmospheric feedbacks (Stammer et al., 2011), redistributions of water mass between the cryosphere, continent and the ocean, may be associated with motions of the Earth’s surface and changes in the geoid and are formulated in the sea level equation (Farrell and Clark, 1976). Furthermore, they may affect the Earth’s inertia and rotation, which produces an additional sea level response (Milne and Mitrovica, 1998), both processes that need to be quantified. In addition, basin-scale gravitational effects related to present-day mass redistributions external to the ocean (atmosphere, hydrological storage; e.g., Vinogradova et al., 2010; Jensen et al., 2013) may mask other effects in coastal oceans and also need to be quantified. At present times such a separation is not possible; however, larger effects related to mass redistributions are expected in response to future releases of freshwater from melting glaciers (Gardner et al., 2013) or polar ice sheets (Shepherd et al., 2012) and it therefore has to be anticipated that this process will be an important one in the future for any coastline.

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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