Data for 2000 supplied to TGZ, previously to "Normal Null".
Documentation added 2001-04-11
Data up to 1984 were high and low waters (mean tide level). MSL thereafter.
Documentation added 2001-06-25
Borkum - data 1963-99 apparently corrected to NN (Normal Null).
Documentation added 2008-01-23
RLR value for Borkum for 2003 and 2004 adjusted from 1.980 to 1.970 following email and attached TGZ information dated 2.11.2007 from Sylvin Mueller Navarra.
Documentation added 2010-08-09
The data used to be measured to Normal Null which is a German datum related to levels at Potsdam near Berlin. It is similar to ODN in the UK or NAP in Holland. It is ususual therefore that the station was made RLR as it 'breaks the rules' of RLR. Data 2000 onwards refers to TGZ.
Documentation added 2016-01-26
A value of MTL-MSL=-81 mm has been applied to the RLR data for the period 1963-1984. This value was derived by Thomas Wahl, using the "k factor method" described in Wahl et al., 61, 701-715, 2011.
Documentation added 2016-08-30
Using values from the BSH website the latitude and longitude for this stations have been updated.
Documentation added 2017-11-15
Data for 2011 onwards has been supplied using RLR as the datum. Therefore no adjustment needs to be applied to the data.
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