As a driving force for convection in fluids. In fluids, on Earth, convection of molecular species is typically orders of magnitude more rapid than the slow migration caused by molecular diffusion due to Brownian motion. As a driving force for phase separation. As a force that helps to determine the free surface morphology of fluids. Even at or near thermodynamic equilibrium, single phases or multiphase systems will be bounded by surfaces or interfaces whose morphology is determined by a balance of forces, including gravitational forces.
Examples arc the shapes of bubbles, droplets, and liquid zones.
Near a critical point. Near such a point, the balance of forces is so delicate that thermodynamic and transport phenomena can exhibit divergent or otherwise anomalous behavior. Thus even the slight inhomogeneity in hydrostatic pressure that arises whenever matter is in a gravitational field can lead to important differences in observable features. In the presence of very weak binding forces. There could be cases, particularly in living systems, in which gravitational forces play a subtle but important role, possibly because of the weak forces that bind macromolecules.