The area around Rabaul undergoes extensive volcanic activity.
National Tidal Facility G.P.O. Box 2100 S.A. 5001 Adelaide
Documentation added 1993-05-27
Stations with authority code G1 are records of Australian (and a few other) mean sea levels supplied by Dr.Bill Mitchell of the National Tidal Facility, Australia in October 1992. The time series have been computed by a homogenization of the data at each station by a process wherein datum shifts are removed by theoretical means, rather than from survey information. For this reason the data are not defined to be "RLR", and should be used in time series work with caution, but they are probably the best thing which can be done for many historical Australian records at the present time.