Data



Data Notes



Extracted from Database

15 Apr 2019

HERMANUS

Station Information

Station ID: 928
Latitude: -34.433333
Longitude: 19.233333
Coastline code: 430
Station code: 71
Country: SOUTH AFRICA
Time span of data: 1958 – 1964
Completeness (%): 88
Date of last update: 01 Jan 1980

Green Arrow: Current Station
Yellow Marker: Neighbouring RLR Station
Red Marker: Neighbouring Metric Station

Please note: In many cases, the station position in our database is accurate to only one minute. Thus, the tide gauge may not appear to be on the coast.

Tide Gauge Data

Plot of monthly mean sea level data at HERMANUS.

Link to larger image of monthly data plot.
Download monthly mean sea level data.

Plot of annual mean sea level data at HERMANUS.

Link to larger image of annual data plot.
Download annual mean sea level data.

Download metric sea level data. Use only with extreme caution.
NOTE: If some of the data are red in the plots above, the 'flag for attention' is set. Please see the documentation below.

Additional Data Sources (guide to additional data sources)

Nearby GNSS Stations from SONEL: HNUS

Station Documentation

Link to RLR information.

Documentation added 1991-06-11

Hermanus 430/071 RLR(1964) is 8.4m below BM H41G

Documentation added 1996-08-28

For discussions of MSL changes and extreme sea levels around Namibia and South Africa, see: G.B.Brundrit, S.Afr.J.Mar.Sci.,16,9-17,1995 and S.Searson and G.B.Brundrit, S.Afr.J.of Science, 91,579-588,1995.

Documentation added 2009-09-24

Heights of chart datum relative to land levelling
datum in South Africa and Namibia: Hermanus
Datum: up to 31st Dec 1978 = -0.619
Datum: 1st Jan 1979 - 31st Dec 1997 = -0.900
Datum: 1st Jan 1998 - 31st Dec 2002 = -0.978
Datum: 1st Jan 2003 onwards = -0.788
Datum is now LAT so unlikely to change.

Data Authority

Hydrographic Office
Maritime Headquarters
Private Bag X1
Tokai 7966