Analysing long-term changes of tidal dynamics in the German Bight (ALADYN)
|Project term:||01.10.2016 bis 30.09.2019|
University of Siegen, Research Institute for Water and Environment (fwu) (details)
Univ.-Prof. Dr.-Ing. Jürgen Jensen
Helmholtz-Zentrum Geesthacht (HZG), Centre for Materials and Coastal Research, Institute of Coastal Research
Lower Saxony State Office for Water Economy, Coastal and Environmental Protection (NLWKN)
|Funding Institution:||Federal Ministry of Education and Research (BMBF) (https://www.bmbf.de/en/index.html)|
The North Sea and the German Bight in particular are very sensitive, complex, and dynamic environments which are highly susceptible to changes (natural or manmade) in the underlying conditions. These changes are often also reflected in the prevailing tidal characteristics usually derived from tide gauge records. Along the German Bight, unusual increases in the mean tidal range (MTR) have been identified since 1950 but increases levelled off in recent years. During this phase, also the usually predominant lunar cycle (having minima in 1951 and 1970, maxima in 1960 and 1979) was masked as shown in Figure 1. The figure shows the MTR at the gauges Dagebüll, Helgoland, Cuxhaven, Leuchtturm (LT) Alte Weser and Norderney (top down). Up to now, all these stations (especially Helgoland and Leuchtturm Alte Weser due their exposed location) are assumed being hardly affected by inhomogeneities. There is a number of studies available trying to describe the interaction between MTR increases and changes in the underlying boundary conditions (e.g. mean sea level, astronomic, atmospheric). However, none of these studies was able to entirely describe the observed changes. An explanation, which has not been investigated in detail, is based on the idea that larger construction measures along the coastline are a major contributor to the MTR increases. This proposal sets up upon this idea and aims at quantifying the influence of construction measures to MTR increases. Therefore, detailed analyses of tidal dynamics will be conducted using both tide gauge records as well as numerical model experiments.
ALADYN is one of 12 collaborative research projects in the funding programme „Küstenmeerforschung in Nord- und Ostsee, KüNO“.