Data



Data Notes



Extracted from Database

09 Sep 2019

KNYSNA

WARNING: QCFLAG EXISTS. PLEASE READ THE DOCUMENTATION.

Station Information

Station ID: 950
Latitude: -34.049444
Longitude: 23.045556
Coastline code: 430
Station code: 86
Country: SOUTH AFRICA
Time span of data: 1960 – 2017
Completeness (%): 72
Date of last update: 15 May 2018

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 KNYSNA.

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

Plot of annual mean sea level data at KNYSNA.

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.

Station Documentation

Link to RLR information.

Documentation added 1991-06-11

Knysna 430/086 RLR(1964) is 9.7m below BM SAN1

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. 1960 - 1972 VALUES BASED ON 8 READINGS PER DAY

Documentation added 2006-11-28

Station flagged data generally suspect. Large spike in dataset Nov/Dec 2002 values very suspect.

Documentation added 2009-09-24

Heights of chart datum relative to land levelling datum in South Africa and Namibia: Knysna Datum: up to 31st Dec 1978 = -0.625 Datum: 1st Jan 1979 - 31st Dec 1997 = -0.900 Datum: 1st Jan 1998 - 31st Dec 2002 = -1.048 Datum: 1st Jan 2003 onwards = -0.788 Datum is now LAT so unlikely to change.

Documentation added 2010-05-11

There appears to be a spike in Nov/Dec 2002 see above. This is possibly real as it appears in several of the S. African stations.

Data Authority

Hydrographic Office
Maritime Headquarters
Private Bag X1
Tokai 7966