The response of active-layer thickness and the ground thermal regime to climatic conditions on the Ulu Peninsula (James Ross Island, northeastern Antarctic Peninsula) in 2011 – 13 is presented. The mean air temperature over this period was – 8.0°C and ground temperature at 5 cm depth varied from – 6.4°C (2011 – 12) to – 6.7°C (2012 – 13). The active-layer thickness ranged between 58 cm (January 2012) and 52 cm (February 2013). Correlation analyses indi- cate that air temperature affects ground temperature more signi fi cantly on snow-free days (R 2 =0.82) than on snow cover days (R 2 = 0.53). Although the effect of snow cover on the daily amplitude of ground temperature was observ- able to 20 cm depth, the overall in fl uence of snow depth on ground temperature was negligible (freezing n -factor of 0.95 – 0.97)