Netherlands Polar Data Center

Summary

The applying researchers developed a unique series of projections for twenty-first century regional sea level change - a valuable addition to the widely published global mean projections. These patterns display several characteristic common features, like an up to 20-30% larger rise along the North Atlantic coasts and in (sub-)tropical regions, and only 50% of the average rise in the subpolar North Atlantic Ocean and off the western Antarctic coast. However, significant uncertainties in the patterns´ amplitude remain, mainly due to uncertainties in the ice sheet contributions. \x0AHere we aim to assess the quality and merits of these projections by a detailed analysis of satellite observations, as that twenty-year record must have captured ~10-30% of the projected twenty-first century rise. \x0ANotably, the observed regional trends in sea level do not resemble the projections, as trends induced by global warming are masked by natural climate variability like El Niño-events. We will extract the long-term regional sea level change from the altimetry record by filtering out the dominant modes of natural variability identified from a statistical decomposition of the observations and fifty-year model re-analyses. The resulting filtered signal, which expectedly contains the sought-after forced regional trends, is compared to the sea level projections. Moreover, taking advantage of our detailed knowledge of the sea level patterns associated with the individual contributions (ocean expansion, glacier melt, Greenland and Antarctic ice sheet mass losses, and groundwater extraction) we analyze which scenario is most likely to be ongoing. The outcomes will benefit policy makers involved in coastal management worldwide.

People involved

Datasets

Publications

Sterlini, P., Dewi Le Bars, et al., 2017. Understanding the spatial variation of sea level rise in the North Sea using satellite altimetry. Journal of Geophysical Research: Oceans 122 (8), 6498-6511

Sterlini, P., de Vries, H., & Katsman, C.A., 2016. Sea surface height variability in the North East Atlantic from satellite altimetry. Climate Dynamics 47 (3-4), 1285-1302