The study of the deposition, distribution, and depletion of snow; the evaluation of hydrologic water balance of basins where appreciable snow occurs; the physics of snow and glacier melt; the storage and transit of liquid water in snow and glaciers, and of possible methods for estimating the rate of stream flow, and the volumes of run-off in basins where snow affects those quantities. See Cooke et al. (2006) PPG 30, 5 on glacier hydrology and supercooling; Hock in U. Huber et al. (2005) on melt modelling; and Hock (2005) PPG 29, 3 for a review of glacier melt.