Secular upheaval of datum level in relation to tsunamigenic earthquake

Abstract

The relation between annual mean sea level and hazardous tsunamigenic earthquakes in the circum‐Pacific seismic zone is studied. A specific example is secular upheaval of datum level on the coast of the Japanese Islands Arc. At present, it is hard to frequently repeat geodetic surveys for finding the datum level's upheaval, and precision of satellite altimetry is hard to resolve this upheaval. On the other hand, an inversed annual mean sea level could be useful for detecting the upheaval, even though consideration should be given to climatological and oceanographical contamination in the variations of the datum level. The inversed annual mean sea level could be used to predict tsunamigenic earthquakes.