Altitude Trends in Permafrost Active Layer Thickness, Kluane Lake, Y.T.

Abstract

On the northwest-facing slopes of Outpost Mountain, Kluane Lake, the permafrost active layer shows an anomalous relationship with altitude, being thinner (typically 40 cm) between 823 and 910 m altitude than above or below this belt. Maximum thicknesses (about 90 cm) are encountered in the shrub tundra at 1310 m elevation. These thicknesses do not correlate with soil types or suprapermafrost drainage, but they do correlate well with the thickness of the organic mat (Of layer) where this exceeds 2.5 cm thickness. The mat apparently acts as a natural insulator.

Key words: Of thickness, active layer thickness, alpine permafrost, altitudinal variations, alpine and subalpine vegetation