Monthly and dekadal mean soil temperatures were evaluated with a use of measurements at depths of 5, 10, 20 and 50 cm, collected during the expeditions 1978—1986 and additionally at depths of 80 and 100 cm during the expeditions 1980—1986. Fourier analysis revealed a phase shift of 1 to 2 dekads between neighboring measurement depths.
On the ground of continuous records of air and soil temperature at standard levels, changes of soil temperature against changes of air temperature have been analyzed at thick and without snow cover. The first example concerns a six-day winter thaw, and the second one a four-day autumn cooling. A particular influence of energy advection has been noted. A delay of changes of soil temperature was found to increase with depth in relation to air temperature. A hypothesis on correlation between air temperature at a height of 5 cm and soil temperature at a depth of 5 cm has been verified.
Average duration of a thermal winter in Hornsund has been determined for 216 days. Average soil temperature at depth of 5 cm in winter is equal —9.8°C. During a spring that lasts 35 days only, soil temperatures at depth of 5 cm indicate distribution nearest to a normal one. Soil temperature distribution in winter substantially differs from the one in spring.
Studies on the thermics, humidity and refreezing rate of two types of periglacial soils of the marine lowlands of the Hornsund area (SW Spitsbergen) were carried out during spring ablation of the snow cover (1.06.—30.06.1987). Structural soil and peat soil (moss community) were chosen. The soils were studied in places almost completely devoid of the snow cover. A considerable differentiation of temperature in vertical profile and of humidity of surface layer in both soils were found. The dynamics of ground water table and the course and depth of spring refreezing of both soils were also different. The differences reflect the different origin of soils and consequently, their different grain-size distribution, physical properties and morphology of both types of soils as well as their water balance.