Storm surges at tide gauge Norderney
Development in the past
In Norderney the maximum water level per season increased over time. Such an increase may be caused by changes in storm activity, increasing mean sea levels and hydro-engineering measures. So far, the observed increase in Norderney is mainly caused by rising mean sea levels.
Data from the current season are preliminary and reflect the present status of the ongoing season.
Interpretation of the figure
Example figure
A storm surge season refers to the period from July to June of the following year. In the figure, the season is denoted by the year in which the season ends. The figure illustrates how the annual maximum water levels have changed over time. The gray line provides an estimate of the linear trend over the period shown. The light gray band illustrates the uncertainties associated with the estimate. The right axis is marked as the severity classification of storm surges (water level relative to the MHW of the reference period 1961-1990 for the North Sea coast). The current season is highlighted by a red-dotted line, and the data of the current season are incomplete until the season ends. The example here shows a snapshot of the tide gauge Cuxhaven at the end of the season 2017/18.
Is the height in the current storm surge season unusual?
The higher the storm surges the less frequent the events. Heights of storm surges of the current season are denoted by colored symbols. They show how long it will take on average until an event of similar height may be observed again (x-axis).
Data from the current season are preliminary and reflect the present status of the ongoing season.
Interpretation of the figure
Example figure
The figure illustrates to what extent the height of the storm surges within the current season (July to June of the following year) is unusual. The gray curve shows a fit of an extreme value distribution to the observed data (gray points). Some of the severe historical events are denoted as open gray circles. Their position relative to the x-axis shows how often on average such an event may be expected. For example, an event similar to the storm surge event that occurred on 3 January 1976 at the tide gauge Cuxhaven may be expected on average once in a hundred years. Events of the current season (season 2017/18 here) are denoted by colored symbols according to their heights relative to the MHW of the reference period 1961-1990.
