Station Information

Station ID: 1
Latitude: 48.38285
Longitude: -4.494838
Coastline code: 190
Station code: 91
Country: FRANCE
Time span of data: 1807 – 2023
Completeness (%): 90
MTL Data: 1807-1835
MTL-MSL (mm): -23
Link to ellipsoid: Available
Date of last update: 30 Jan 2024

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.

Additional Data Sources (guide to additional data sources)

Nearby GNSS Stations from SONEL: GUIP, BGBC, BRST
Nearby Real Time Stations from VLIZ: bres
Fast Delivery Data from UHSLC station 822: hourly and daily
Research Quality Data from UHSLC station 822: hourly and daily

Station Documentation

Link to RLR information.

Documentation added 1993-07-12

Brest 190/091 RLR(1964) is 12.5m below NGF no1

Documentation added 2007-01-21

Older data from Brest are taken from the original volumes of the Publications Scientifiques. In those, 1807-35 are said to be Mean Tide Level and 1846 onwards true Mean Sea Level. At Brest MSL is 23mm above MTL (some estimates say 29 mm), see Woppelmann et al. Ocean Dynamics, 56, 487-497, 2006 (and beware that the equation top of page 495 should read MTL-MSL). (NOTE: 23 and 29 mm values switched to better reflect paper. 26-Jan-2016)

Documentation added 2009-07-21

All monthly means 1937, 1939-1943 replaced and small corrections made to 1917 following the work of Nicolas Pouvreau of the University of La Rochelle.

Documentation added 2014-08-28

After investigation the RLR diagram has been revised. Primary benchmark remains the same but the name has been changed to agree with SONEL. Benchmark name is now NO-47. The RLR factor has also been changed when a 2mm discrepancy was found from the original diagram. RLR factor for 1996 onwards is now 2.959.

Documentation added 2014-09-24

Using values from the SONEL website the latitude and longitude values have been revised. Additional data for 1857-1860 were included in the SONEL data this has now been added to the database.

Documentation added 2016-01-26

A value of MTL-MSL=-23 mm has been applied to the RLR data for the period 1807-1835. This value was taken from the Wöppelmann et al. reference above.

Data Authority

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29200 BREST