Submitted to: Soil Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 13, 1998
Publication Date: N/A
Interpretive Summary: Frost depth governs how deep water pipes should be buried, the ability to forecast stream flow, the potential for river flooding, and the axle load of vehicles which can be driven across wet soils. We compared the ability of four frost models to simulate soil frost depth under a range of climate and soil conditions. The best prediction of frost depth is achieved with the most complex models used in our study. The most simplistic model grossly overestimated frost depth in some circumstances and grossly underestimated frost depth in other circumstances, yet this model is used to forecast the depth of frozen soil as an aid in assessing the potential for soil erosion. Agencies such as NRCS or NWS which have interest in estimating frost depth will use this information when selecting a model to predict soil frost depth.
Technical Abstract: Four soil models capable of simulating soil frost depths and temperatures were evaluated for their ability to predict the depth and timing of soil frost at sites in northern and Midwestern North America. The evaluation was carried out by comparing model simulation results to observed field data. The data used in the comparisons came from two sites, one near Delta Junction, AK, characterized by a cryaquept with grass cover and the other near Morris, MN, characterized by a haploboroll with corn stubble. The two models that use a finite difference solution to heat flow in the soil profile both predicted frost depth with reasonable accuracy, at least when the simulated snow depth closely matched the recorded snow depth. The other two models work by balancing heat fluxes, and generally gave less accurate results. One of the two showed extreme sensitivity to snow cover and both showed a lack of sensitivity to the different climates at the two locations. The results illustrate the importance of snow cover in controlling soil frost as well as the difficulty in accurately simulating soil frost.