Otto, J.‐C., Keuschnig, M., Götz, J., Marbach, M. and Schrott, L., 2012. Detection of mountain permafrost by combining high resolution surface and subsurface information – an example from the Glatzbach catchment, Austrian Alps. Geografiska Annaler: Series A, Physical Geography, 94, 43–57. doi:10.1111/j.1468‐0459.2012.00455.x Abstract Permafrost distribution in mid‐latitude mountains is strongly controlled by solar radiation, snow cover and surface characteristics like debris cover. With decreasing elevation these factors have to counterbalance local positive air temperatures in order to enable permafrost conditions. We combine high resolution surface data derived from terrestrial laser scanning with geophysical information on the underground conditions using ground penetrating radar and electrical resistivity tomography and ground surface temperature data in order to understand the effects of surface characteristics on permafrost distribution in an Alpine catchment, Austrian Alps (Glatzbach, 47°2′23.49″ N; 12°42′33.24″ E, 2700–2900 m a.s.l.). Ground ice and permafrost is found above an elevation of 2780 m a.s.l. on north‐east facing slopes in 2009, previous studies detected permafrost at the same site at 2740 m a.s.l. in 1991. Analysis of surface roughness as a proxy for grain size distribution reveals that the lower boundary of discontinuous and sporadic permafrost is lowered on rough surfaces compared to fine‐grain zones. At the same location modelled potential summer solar radiation in coarse grain zones is reduced by up to 40% compared to surfaces of fine grain sizes. The mostly patchy permafrost distribution at the Glatzbach can therefore be attributed to local surface cover characteristics, particularly regolith grain size and its influence on solar radiation. We conclude that the analysis of ground surface characteristics using very high resolution terrain data supports the assessment of permafrost in Alpine areas by identifying rough surface conditions favouring permafrost occurrence.

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Abstract. This paper focuses in particular on clastic sediment fluxes on talus slopes. Using orthophoto interpretation, field measurements and GIS-techniques, a quantification of areas and volumes of active sediment transfer related to specific landform units was achieved for different spatial scales. Closer investigation of a single landform complex, more specifically a talus sheet/ debris cone-complex, brought to light that remobilisation can overbalance sediment input by a factor of 57. This could be an indication of what may be expected in the whole catchment. At present. approximately 9% of the research area (3 km2), comprising talus slopes and valley bottom, is characterised by sediment transfer mainly through gravilational and fluvial processes. A comparison of the vast volumes (117.174 m3) derived from these active areas of recent sediment transfer and the volume of the entire valley fill (0.07 km3) indicates, however, that the largest part must be related to remobilised sediments and cannot be considered as sediment input from the adjacent rockwalls. This conclusion is also supported by direct measurements of sediment input.