Permafrost distribution from BTS measurements (Sierra de Telera, central Pyrenees, Spain):: Assessing the importance of solar radiation in a mid-elevation shaded mountainous area

Permafrost distribution was predicted from measurements of basal temperatures of the winter snow cover using a GIS-based empirical-statistical modelling approach in a mid-elevation mountainous area, the northern slope of the Sierra de Telera (central Pyrenees, Spain). A total of 223 basal temperature of snow (BTS) measurements were made over 3 years and a multiple linear regression analysis was performed to model the relationship between BTS measurements and three predictor variables: May solar radiation, elevation and snow-cover persistence. The snow-cover persistence factor proved non-significant and was excluded from the final regression analysis. The model used was statistically significant, and predicted permafrost distribution moderately well (K = 0.52) and with an overall accuracy of 0.79. The results show the importance of solar radiation as an explanatory variable for permafrost conditions in a mid-elevation mountain area with steep topography. Copyright (C) 2007 John Wiley & Sons, Ltd.