Abstract
Continuous records have been maintained since January 1952 of soil temperatures in a forestry plantation near Ballater, Aberdeenshire. The data have led to the following conclusions:
The mean annual temperatures are practically the same throughout the soil profile.
Inversions of the temperature profile occur in April and August.
The frostβfree periods have been June to September in the air and May to October in the soil at a depth of 1 in. Frosting at a depth of 6 in. has been restricted to the months of December and January, and no frost temperatures have been recorded at depths of 12 in. or more.
During the two years 1952 and 1953 temperatures of 0Β°C or less have been noted on 167 days in the air, 109 days at a depth of 1 in., and 12 days at a depth of 6 in.
There is severe damping of temperature amplitudes with increasing depth, the diurnal variations being very small at depths exceeding 12 in. Estimates of thermal diffusivities have been made for the soil strata from ground level to 1 in. and from 1 in. to 6 in.
It is found that good estimates of weekly mean temperatures can be obtained from readings of the daily maximum and minimum temperatures.