Hydrological Loading

Hydrological loading refers to the deformation of the Earth’s crust caused by temporal variations in surface and subsurface water masses, including precipitation, soil moisture, snow, ice, rivers, lakes, and groundwater. Changes in water storage redistribute mass and exert variable loads on the solid Earth.

In geodesy, hydrological loading is observed through surface displacements measured by GNSS and through gravity field variations detected by satellite gravimetry missions (e.g., GRACE/GRACE-FO). Modeling and correcting for hydrological loading effects are essential for precise positioning, reference frame stability, and the interpretation of geodetic time series in studies of climate variability and Earth system processes.