The Botany of Iceland - 01.12.1930, Page 180
170
H. M0LHOLM HANSEN
Table 34. Annual Variations in the Temperature
of tlie Air, Snovv, and Soil in Sodankylá (Finland, 67° 22' N., 26° 39' E.).
The investigations cover the period from November 1915 to October
1917 (cf. Keranen 1920, pp. 52-53).
November— April June— September November December January February March April May o •s July August September O o Average y o u o & 2
Depth of snow cm 47.8 » 1(5.1 31.9 45.8 62.5 70.5 68.8 » » » » » » » »
Precipitation mm » 52.6 25.8 23.3 33.1 25 5 36.4 36.3 49.7 65.3 68.1 74.6 75.0 56.6 »
Clouds » » 8.2 7.9 8.1 7.7 6.3 7.9 7.8 6 9 7.0 8.0 7.1 8.8 7.6 »
Temperature of
air C° -4-12.1 10 (i -4 8.2 -417.7 -414.0 -415.0 -413.6 -44.1 1.2 11.9 14.4 11.7 4.5 41.2 -v-2.5 »
Snow 0 cm -4-14.2 » -4-9.6 -418.9 -416.1 -417.0 -415.1 -45.9 * » » » » » » »
-=-10 » » » * -410 1 -410 2 -410.8 -410.4 -43.4 * » » » » » »
-=-20 » » » * * —7— 7.2 -4 8 2 -4 8.2 -43.0 * » » » » » »
-h30 i » » * * -4 4.9 -4 6.3 -4 6.6 -42.6 * » » » » » » »
-j-40 j » » » * * -4 4.8 -4 5.4 * * » » » >1 » » »
-4- 50 » » > » » » -4 3.7 -4 4 3 * * » » »: » » »
-=- 60 » » » ] » » » » -4 3.4 * * * 1 » » » » »
Soil 0 cm -4- 2.7 13 2 -42.8 -4 4.0 -4 3.3 -4 2.8 -4 2.7 -41.2 1.9 15.3 18.3 14.0 5.1 - 40.5 3.2 22.3
-10 » . . .. -4- 1.9 12.2 -4-1.1 -4- 2.5 -4 2.6 -4 2.1 -4 2 1 -41.0 0.9(11.8 16.7 13.8 6.5 1.0 3.3 19.3
-25 » -4- 1.4 11.0 -40.4 -4 1.7 -4 2.1 -4 1 7 -4 1 8 -41.0 0.4 9.3 14.9 13.0 7.0 1.4 3.1 17.0
-40 » -4- 1.1 10.7 0.4 -4 1.2 -4 1.8 -4 1.6 -4 1.6 -40.9 0.2 7.9 14.3 13.1 7.7 2.2 3.2 16.1
-80 » .. . -4- 0.1 9.0 1.3 0.6 -4 0.2 -4 0 6 -4 1.0 -40.8 H-0.2 5.4 11.8 11.9 8.1 3.1 3.2 12.9
-120 » 0.8 7.2 2.4 1.3 0.6 0.3 0.1 -4 0.1 0.0 1.9 8.4 10.1 9.5 4.6 3.2 10.2
-160 » ; 1.1 (5.6 2.7 1.7 0.9 0.6 0.3 0.1 0.1 1.5 7.0 9.4 8.4 4.9 3.1 9.3
snovv. At the beginning of the winter when the snow lies lightly,
a layer of a certain depth has a greater power of isolation than
a layer of the same depth at the close of the winter, at which tirne
the layer has grown more compact. Thus the table shows that the
diflerence in temperature between corresponding layers is greatest
at the beginning of a snow-period and decreases progressively until
it attains its lowest value at the close of the winter. This fact has
a certain practical significance in that the temperature at the surface
of the soil will never be very much lowrer at the beginning of the
winter than later on, in spite of the much slighter snow-covering at
the beginning of the winter.
Investigations on the temperature conditions in soil wdth a
different water content, of a different consistence, and with a dilferent