An Approximation of Probable Permafrost Occurrence

Describes use of air temperatures to determine permafrost presence for engineering purposes. Annual mean temperature and thawing index (a yearly summation of daily mean temperature over 32 F) in 61 localities of northern Canada were compared with reported permafrost occurrences. The latter are divided into four categories: free of permafrost; discontinuous permafrost; continuous permafrost in forest, and in tundra. Correlations were found in all but twelve of the localities; the latter are considered individually and in some, permafrost was uncertain.