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Mergili, M., Kopf, C., Müllebner, B. and Schneider, J.F., 2012. Changes of the cryosphere and related geohazards in the high-mountain areas of Tajikistan and Austria: a comparison. Geografiska Annaler: Series A, Physical Geography, 93, 79-96. doi:10.1111/j.1468-0459.2011.00450.x ABSTRACT This paper quantifies recent glacier changes and possible future permafrost retreat in the Austrian Alps and the Pamir and Alai Mountains of Tajikistan (Central Asia), two mountainous areas with striking differences in climate and hypsometry, but also in economy and research history. The aim of the comparative study is to improve the understanding of regional differences as a baseline for further research and for a differentiated evaluation of possible socio-economic implications. Besides a review of the available literature, multi-temporal remote sensing of glaciers of selected areas as well as additional helicopter and field surveys were conducted. The Tajik glaciers displayed a differentiated behaviour during the investigation period 1968-2009, with a strong trend to retreat - at least since 2002. More than 100 pro- and supraglacial lakes have been forming or growing in the southwestern Pamir. Destructive outburst floods of such lakes have occurred there in the recent past. Almost all Austrian glaciers are in an advanced stage of retreat, a trend which continues at enhanced rates. Comparatively few glacial lakes exist in the direct forefields of the glaciers. Potential permafrost distribution maps for the present and the future were produced for Tajikistan and Austria by adapting an empirical model developed in Switzerland. In absolute terms, the highest loss was predicted for the Pamir. The expected relative loss in the same area is moderate compared to the rest of Tajikistan and particularly to Austria, where the model predicted the disappearance of more than 90% of the potential permafrost until the end of the twenty-first century. [ABSTRACT FROM AUTHOR]

Four different sites in the highlands of central Iceland have been investigated for permafrost occurrence using two-dimensional resistivity imaging. The results of the surveys indicate the presence of shallow permafrost of low to medium resistivity. The distribution pattern is spatially heterogeneous which is consistent with permafrost at the fringe of seasonal frost. These sites are likely to react rapidly to changes of the environmental boundary conditions, therefore future research should include monitoring for detecting the early impact of climate change on permafrost degradation. The extent to which periglacial morphodynamics and sediment fluxes are influenced by permafrost and/or seasonal frost and potential permafrost degradation is hard to determine. Hence, long-term monitoring approaches for both permafrost and sediment dynamics are essential. [ABSTRACT FROM AUTHOR]