Rockwall retreat rates are important indicators of geomorphological denudation and accumulation work. Quantitative data has been provided by a number of field studies [Krautblatter & Dikau 2007]. Rockfall has been ascribed as the most significant agent of rockwall retreat. However, the role of snow avalanches should not be underestimated, as they are an efficient transport agent from high to lower relief on steep slopes. Still, quantification of their particular importance is rare and often limited to extreme events. Rockwall retreat rates from the High Arctic are sparse and the geomorphological effect of snow avalanches is only ascribed to full-depth, slush and dirty spring avalanches. However, recently Eckerstorfer et al. (submitted)identified cornices, situated on the leeward edges of the extensive plateau mountains in central Svalbard, as agents of erosional significance. Highly weathered sedimentary sandstone is incorporated into cornices during their onset and plucked out when the cornices deform downslope. The sediment is then transported downslope by cornice fall avalanches, when cornices collapses. A study by Siewert et al. (submitted) from central Svalbard showed that Holocene rockwall retreat rates on slopes with cornices on top where 100 % higher than on slopes without.
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