Storm surges at tide gauge Norderney
Development in the past
In Norderney storm surge frequency 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 storm surge frequencies 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 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 frequency in the current storm surge season unusual?
Blue curve below the orange one:
Within the current season, fewer storm surges are (so far) observed than usual.
Blue curve above the orange one but within the yellow area:
So far storm surges in the current season are more than normal (the long-term average), but not uncommon compared to the past.
Blue bar higher than the gray bar:
In the reference period (1961-1990) there was no season in which the number of storm surges within that month was higher than within the current season.
Interpretation of the figure
Example figure
The figure shows the extent to which the current storm surge season compares with previous ones and the extent to which it is unusual. Shown is an example of the season 2017/18 at the tide gauge Cuxhaven. The gray bars illustrate the maximum number of storm surges within a given month observed in 1961-1990. The blue bars denote corresponding numbers for the current season. The blue curve shows the overall number of storm surges from the beginning of the season until today (date of the visit of this web page). The corresponding long-term average of the reference period 1961-1990 is illustrated by the orange curve. The yellow shaded region marks the area into which 94% of the seasons at this gauge fall.
The example shown illustrates that the season 2017/18 at the tide gauge Cuxhaven was slightly more active than on average. There are relatively frequent storm surges at the beginning while fewer events occurred towards the end. In total, the number of storm surges in this season was slightly above average but still well within the year-to-year variability.
