This project investigates how surface load variations, caused by continental water, ocean mass changes, and atmospheric pressure fluctuations, influence seismicity in subduction zones. Using satellite gravimetry data, we compute long-wavelength stress changes in the lithosphere up to the depth of 100 km and integrate them with global earthquake focal mechanism data to analyze how surface loading interacts with tectonic stress fields. The research aims to identify conditions where loading amplifies tectonic stress and promotes fault instability, improving our understanding of external forcing on seismic hazards in subduction zones.