Variation of the Monthly Mean Seasurfacetemperatures- and -salinities at Helgoland-Reede
Charts at Helgoland - Reede
Along with the time-series Den Helder (Netherlands), the t/s Helgoland-Reede represents one of the longest
and most complete series on the European shelf. The first measurements were taken in the 1870s by the then
Biologische Anstalt Helgoland (now AWI) and have been continued to this day (Wiltshire et al., 2004).
Any data gaps encountered in particular due to WW I and II were successfully closed using measurements taken
by nearby light vessels (Becker et al., 1997); thus, the Helgoland time series provides us with a constant
record of temperature and salinity levels in the south-eastern North Sea covering a period of 140 years.
Starting in 1873, the monthly mean sea surface temperatures and salinity levels were recorded for each year.
The individual charts show the high variability of parameters over the year caused by meteorological changes,
tides, and runoff from the river Elbe. The climatological mean - from 1873 up to the closed prior year - including
standard deviation, underscores the notably high variability encountered in the German Bight.