  Variations in sea-level, based on tide gauge data (GSLTG) and on combining
tide gauges and satellite data (GSLl) are subjected to singular spectrum
analysis (SSA), to determine their trends and periodic or quasi-periodic
components. GLSTG increases by 90 mm from 1860 to 2020, a contribution of 0.56
mm/yr to the mean rise rate. Annual to multi-decadal periods of ~90/80, 60, 30,
20, 10/11, and 4/5 years are found in both GSLTG and GSLl. These periods are
commensurable periods of the Jovian planets, combinations of the periods of
Neptune (165 yr), Uranus (84 yr), Saturn (29 yr) and Jupiter (12 yr). These
same periods are encountered in sea-level changes, motion of the rotation pole
RP and evolution of global pressure GP, suggesting physical links. The first
SSA components comprise most of the signal variance: 95% for GSLTG, 89% for
GSLI, 98% for GP, 75% for RP. Laplace derived the Liouville-Euler equations
that govern the rotation and translation of the rotation axis of any celestial
body. He emphasized that one must consider the orbital kinetic moments of all
planets in addition to gravitational attractions and concluded that the Earth's
rotation axis should undergo motions that carry the combinations of periods of
the Sun, Moon and planets. Almost all the periods found in the SSA components
of sea-level (GSLl and GSLTG), global pressure (GP) and polar motion (RP), of
their modulations and their derivatives can be associated with the Jovian
planets. It would be of interest to search for data series with longer time
spans, that could allow one to test whether the trends themselves could be
segments of components with still longer periodicities (e.g. 175 yr Jose
cycle).
