Submitted to: Encyclopedia of Water Science
Publication Type: Book / Chapter
Publication Acceptance Date: June 10, 2002
Publication Date: January 1, 2003
Citation: Baker, J.M. 2003. Water movement in frozen soil. Encyclopedia of Water Science. p. 314-316. Technical Abstract: Water movement in freezing and thawing soils is dominated by two key features the steep drop in water potential that accompanies freezing (1.2 Mpa degrees C-1) and the sharp decrease in permeability of frozen versus unfrozen soils. The former is unavoidable and is expressed by the Clausius-Clapeyron equation for phase equilibrium. It gives rise to the latter by providing a driving force that favors water movement toward the freezing front, where it can fill available pore space with ice, thus limiting subsequent infiltration. This happens most readily in moist, fine-textured soils and soils with free water near the surface (shallow water tables). Dry soils and soils with abundant macroporosity are less affected and tend to permit infiltration at rates nearer to their unfrozen values.