Abstract
Numerous lobate- or tongue-shaped debris accumulations, mostly interpreted as rock glaciers, have recently been recognized in the High Tatra Mts., Slovakia (49°10' N, 20°08' E). These prominent landforms arise due to creep of voluminous debris-ice mixtures, and as such they are excellent indicators of present or past permafrost existence.
Hence rock glaciers are extensively utilized to model the distribution of permafrost in mountain areas. However, commonly applied rules of thumb may not be entirely indicative to discriminate particularly between the inactive (permafrost in disequilibrium with present climate) and relict (without permafrost) rock glaciers, which may substantially complicate permafrost modelling.
Accordingly, the information about their thermal state is essential to calibrate and validate regional permafrost models. Limited ground temperature data have been, however, available from the High Tatra Mts. to date and therefore, we bring the updated and enhanced results from the thermal investigations of eleven rock glaciers located in the Slavkovská dolina and Veľká Studená dolina valleys at elevations between 1832 and 2090 m asl.
The results suggest that permafrost occurrence is probable or possible in a total of ten rock glaciers, while its absence is probable only in one of the investigated landforms. We classify the latter form as relict and other two rock glaciers are suggested to be in inactive/relict state.
Six rock glaciers are believed to be inactive and two even active/inactive. In most cases, however, permafrost likely occurs in a form of isolated patches or discontinuously and presumably degrades under present climate conditions.