PhD project: Keeping your feet dry in rising tides: Trends and environmental impacts of recent relative sea level rise in coastal Norway.
My project focusses on recent relative sea level (RSL) change in Norway. Relative sea level in Norway has been rising and falling after the last deglaciation. However, since the last period of RSL rise (named the Tapes transgression) reached its maximum approximately 7000 cal yr BP, Norway has experienced a gradual RSL fall to modern levels. This sea level fall has mainly been driven by glacio-isostatic rebound (GIA), the rebound of the land's surface caused by the disappearance of the weight of the Fennoscandian ice sheet after the deglaciation.
Palaeo-RSL data covers the Holocene up to 2000 cal yr BP. Other available data comes in the form of tide gauge records, which cover approximately the last 100 years of RSL change. The tide gauge record of Norway shows that sea level in northern and southwestern Norway has been rising since the start of measurements. Furthermore, this rise has been accelerating, while the RSl fall in the other areas have been decelerating. Projections for future RSL changes also indicate that the whole Norwegian coastline will be affected by RSL rise at the end of the century. This change in trend shows that global sea level rise has caught up/is catching up with the land uplift in Norway.
With my research, I aim to close the gap between the palaeo-data record and the observational tide gauge record. In doing so, I want to create new datapoints, covering the last 2000 years, which enables the construction of new relative sea level curves. In addition, this will make it possible to pinpoint the moment when the trend of RSL rise started in northern and southwestern Norway. This data will help to improve and constrain future RSL projections.
This aims are translated into 3 research questions and 3 different projects:
Are the rates of recent (past few centuries) relative sea level rise the highest in the last 2000 years?
Did the transition of falling/standstill to rising relative sea level in Norway happen during the last 2000 years?
Are earlier transgressions, such as the Tapes transgression, similar (and useful as analogs) to contemporary changes in relative sea level?
I will try to answer these questions by studying sediment from saltmarshes and (nearly) isolated basins with a wide range of sedimentological analytical methods (e.g. XRF-analysis, stable isotopes & C/N analysis, microfossils, etc.).