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| Natura: | Dataset Open Access |
| Lingua: | en |
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PANGAEA
2012
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| Accesso online: | https://doi.org/10.1594/PANGAEA.869805 |
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| _version_ | 1867168179391823872 |
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| author | Lieb, Gerhard Karl Kellerer-Pirklbauer, Andreas Kleinferchner, Harald |
| author_facet | Lieb, Gerhard Karl Kellerer-Pirklbauer, Andreas Kleinferchner, Harald |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Rock glaciers are striking features in high mountain environments indicating permafrost conditions during the period of formation and activity. Within the framework of the Alpine-Space-Project PermaNET, a new polygon-based inventory of rock glaciers has been elaborated comprising the alpine areas of central and eastern Austria as part of an inventory covering the entire European Alps. The establishment of the new inventory was primarily based on an existing point-based inventory which was re-evaluated and amplified using currently available orthophotos, different digital elevation models and derivatives thereof. Further topographic information such as for instance elevation of lower and upper limits, maximum length and width, area and activity degree were gathered in an attribute table. All different parameters were analyzed regarding the entire investigation area, differences between the relevant federal provinces of Austria and between the single mountain regions. These regions were distinguished by differences of mainly climate, topography and present glacier extent. As a result, data on altogether 1647 rock glacier polygons or units were gathered in the inventory comprising 1430 monomorphic rock glaciers (rock glacier with one unit/generation) and 98 polymorphic rock glaciers (with two to five distinct units). 1300 rock glacier units have been classified as relict (no permafrost anymore) covering 97.7 km**2 in total, whereas 347 units with a total area of 21.3 km**2 as intact (containing permafrost) ones. The mean lower limit of relict rock glacier units with a mean size of 0.075 km**2 is situated at 2102 m a.s.l.. For the intact ones the respective values are 0.061 km**2 and 2515 m a.s.l.. Interpreting the results leads to the conclusion that the dominance of relict rock glaciers is due to fact that the summit elevations decrease towards the east thus restricting current permafrost occurrence to limited areas. Furthermore, "normal glaciers" still occupy rock glacier favourable sites particularly in central Austria. Intact rock glaciers usually developed over millennia primarily during the Holocene. In contrast, relict rock glaciers began to form during and after the Lateglacial deglaciation of cirques which generally occurred earlier in the east compared to the west of the investigated area. However, slope orientation was relevant for the deglaciation pattern causing formation of older rock glaciers on „warm“ slopes whereas on “cold” slopes rock glaciers are possibly of younger age. Although a comprehensive overview on rock glacier distribution can be given by our study, drawbacks of this study are the varying quality of information sources, the absence of data on surface motion (except for single rock glaciers) and missing absolute dating of rock glacier surfaces. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_869805 |
| institution | PANGAEA |
| language | en |
| publishDate | 2012 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Second rock glacier inventory (RGI2) of Central and Eastern Austria, link to Shapefile Lieb, Gerhard Karl Kellerer-Pirklbauer, Andreas Kleinferchner, Harald RGI2aut_ce Rock glaciers are striking features in high mountain environments indicating permafrost conditions during the period of formation and activity. Within the framework of the Alpine-Space-Project PermaNET, a new polygon-based inventory of rock glaciers has been elaborated comprising the alpine areas of central and eastern Austria as part of an inventory covering the entire European Alps. The establishment of the new inventory was primarily based on an existing point-based inventory which was re-evaluated and amplified using currently available orthophotos, different digital elevation models and derivatives thereof. Further topographic information such as for instance elevation of lower and upper limits, maximum length and width, area and activity degree were gathered in an attribute table. All different parameters were analyzed regarding the entire investigation area, differences between the relevant federal provinces of Austria and between the single mountain regions. These regions were distinguished by differences of mainly climate, topography and present glacier extent. As a result, data on altogether 1647 rock glacier polygons or units were gathered in the inventory comprising 1430 monomorphic rock glaciers (rock glacier with one unit/generation) and 98 polymorphic rock glaciers (with two to five distinct units). 1300 rock glacier units have been classified as relict (no permafrost anymore) covering 97.7 km**2 in total, whereas 347 units with a total area of 21.3 km**2 as intact (containing permafrost) ones. The mean lower limit of relict rock glacier units with a mean size of 0.075 km**2 is situated at 2102 m a.s.l.. For the intact ones the respective values are 0.061 km**2 and 2515 m a.s.l.. Interpreting the results leads to the conclusion that the dominance of relict rock glaciers is due to fact that the summit elevations decrease towards the east thus restricting current permafrost occurrence to limited areas. Furthermore, "normal glaciers" still occupy rock glacier favourable sites particularly in central Austria. Intact rock glaciers usually developed over millennia primarily during the Holocene. In contrast, relict rock glaciers began to form during and after the Lateglacial deglaciation of cirques which generally occurred earlier in the east compared to the west of the investigated area. However, slope orientation was relevant for the deglaciation pattern causing formation of older rock glaciers on „warm“ slopes whereas on “cold” slopes rock glaciers are possibly of younger age. Although a comprehensive overview on rock glacier distribution can be given by our study, drawbacks of this study are the varying quality of information sources, the absence of data on surface motion (except for single rock glaciers) and missing absolute dating of rock glacier surfaces. |
| title | Second rock glacier inventory (RGI2) of Central and Eastern Austria, link to Shapefile |
| topic | RGI2aut_ce |
| url | https://doi.org/10.1594/PANGAEA.869805 |