Link to RLR information.
=========================== FOLLOWING PSMSL DOCUMENTATION ADDED 04-AUG-94 : For a discussion of interannual variability of sea level along the coasts of Pakistan and India, see Clarke and Liu, Journal of Physical Oceanography, 24, 1224, 1994. =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 29-JUL-93 : Anomalously large value June 1946 and low values at end of 1946 (just before a data gap) - correct as received from authority. =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 2002Jun14 : Data for 1916-20 are MSL and were obtained from the Survey of India, Dehra Dun. Data 1937-48 are MTL (Mean Tide Level) and were also obtained from the Survey of India. Data 57 onwards are MSL. 1957-65 were obtained from the Pakistan Meteorological Department, while 1966-85 from National Institute of Oceanography. 1986-87 were obtained from the University of Hawaii Sea Level Center using data supplied by the NIO. =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 2002Jun17 : Karachi 490/021 RLR(1947) is 9.7m below BM 1PP (circa 1920) =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 2002Sep25 : New data from Pakistan Navy for 1987 replaces TOGA data for Jan-Apr and Dec =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 11-Mar-2009 : The gauge at Karachi has been resited and is now no longer on Manora Island. The new gauge has been levelled in to the old one. 2007/8 one minute sea level data downloaded from the IOC Sea Level Station Monitoring Facility Ostend. This is then converted to 15min. data for processing. 2007/8 monthly and annual mean sea level values have now been extracted from the data. As the relationship for the prime bench mark remains the same there is no need to alter RLR. Details of the bench marks has been derived from site installation information. Copies of these have been included in the port files and RLR file for reference. =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 26-Jan-2016 : A value of MTL-MSL=10 mm has been applied to the RLR data for the period 1937-1948. This value was derived by Philip Woodworth in preparation of his MTL/MSL manuscript. In this case two values were derived using from the GESLA2 (high-frequency tide gauge) dataset using harmonic constituents: 12 mm and 2 mm. In addition, he obtained a value of 10 mm using the historic databank of harmonic tidal constants gathered by the International Hydrographic Organization.
Hydrographer of the Pakistan Navy Hydrographic Department Naval Headquarters 11, Liaquat Barracks Karachi PAKISTAN