ИССЛЕДОВАНИЕ ВАРИАЦИЙ КОЭФФИЦИЕНТА ГРАВИТАЦИОННОГО ПОЛЯ J2 МЕТОДОМ ССА
Journees 2019 have been marked by record numbers of participants and communications. Therewere 118 attendants coming from 21 countries over the 5 continents. The scientific programincluded 58 oral presentations and 38 posters. Presentations were split into five sessions, alternatingastrometry (sessions I and III), Earth rotation changes (Session II/IV) and solar system dynamics(session V). Of particular interest were the communications dedicated to the results of the Gaiamission and its possible future prolongation in IR band (Session I), the realization of the InternationalCelestial Frame III (session III). In session II, many interesting talks were devoted to the centennialof the ”Earth rotation” IAU commission
Using multichannel singular spectrum analysis (MSSA) we decomposed climatic time series into principal components, and compared them with Earth rotation parameters. The global warming trends were initially subtracted. Similar quasi 60 and 20 year periodic oscillations have been found in the global mean Earth temperature anomaly (HadCRUT4) and global mean sea level (GMSL). Similar cycles were also found in Earth rotation variation. Over the last 160 years multi-decadal change of Earth's rotation velocity is correlated with the 60-year temperature anomaly, and Chandler wobble envelope reproduces the form of the 60-year oscillation noticed in GMSL. The quasi 20-year oscillation observed in GMSL is correlated with the Chandler wobble excitation. So, we assume that Earth's rotation and climate indexes are connected. Despite of all the clues hinting this connection, no sound conclusion can be done as far as ocean circulation modelling is not able to correctly catch angular momentum of the oscillatory modes.