1959-72, 1976-81, 1983-85 FCODE=HL, Some months based on incomplete data more details available on request.
Documentation added 1994-09-21
Gauge was a stilling well (instrument made at Port of Bristol to Tidal Institute specification) until the end of 1984 with tabulations supplied by the Port of Bristol authority.From 21 November 1984 the gauge has been an "A Class" bubbler.
Documentation added 2001-01-02
Recent work on vertical land movements in the UK can be found from the University of Nottingham web site:http://ukcogr.iessg.nottingham.ac.uk/~eosi/
Documentation added 2001-03-21
Avonmouth - 170/171 RLR(1992) is 15.8m below TGBM ST 5057 7881
Documentation added 2009-01-28
Treat data 2000 onwards as suspect.
Documentation added 2010-06-08
Although the Avonmouth gauge is still operational the jetty on which the gauge stands is collapsing. A replacement gauge has been installed at Portbury.
Documentation added 2016-01-22
A value of MTL-MSL=127 mm has been derived using from the GESLA2 (high-frequency tide gauge) dataset using harmonic constituents. As the correction is only applied to RLR data and the data during the periods 1959-1972, 1976-1981, and 1983-1985 are metric, it is not used in the data set. Should these periods become RLR in future, however, a correction for MTL-MSL would be needed. The 001 flag has been set only because this correction is highly uncertain.
British Oceanographic Data Centre National Oceanography Centre Joseph Proudman Building, 6 Brownlow Street Liverpool L3 5DA