An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland
An area of permanent snow and frozen ground was studied at the end of summer seasons during the years 1990–1993 near the summit of Ridnitvsohkka fell, which at 1317 m a.s.l. is the second highest peak in Finland. The eastern flank of Ridnitvsohkka has the most extensive area of permanent snow (3 km2...
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Geological Society of Finland
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ftdoajarticles:oai:doaj.org/article:dcd101c747dd47639f90c9bf612442e4 2023-05-15T16:37:38+02:00 An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland H. Hirvas P. Lintinen P. Kosloff 2000-12-01T00:00:00Z https://doi.org/10.17741/bgsf/72.1-2.003 https://doaj.org/article/dcd101c747dd47639f90c9bf612442e4 EN eng Geological Society of Finland http://www.geologinenseura.fi/bulletin/Volume72/Hirvasetal.pdf https://doaj.org/toc/0367-5211 https://doaj.org/toc/1799-4632 doi:10.17741/bgsf/72.1-2.003 0367-5211 1799-4632 https://doaj.org/article/dcd101c747dd47639f90c9bf612442e4 Bulletin of the Geological Society of Finland, Vol 72, Iss 1-2, Pp 47-56 (2000) periglacial features snow firn permafrost till drilling Ridnitvsohkka Lapland Finland Geology QE1-996.5 article 2000 ftdoajarticles https://doi.org/10.17741/bgsf/72.1-2.003 2022-12-31T13:59:56Z An area of permanent snow and frozen ground was studied at the end of summer seasons during the years 1990–1993 near the summit of Ridnitvsohkka fell, which at 1317 m a.s.l. is the second highest peak in Finland. The eastern flank of Ridnitvsohkka has the most extensive area of permanent snow (3 km2) in Finland, while the summit region represents the highest single area of basal till devoid of vegetation cover and displaying patterned ground features. The ground penetrating radar results show that the form of the snowfield does not conform to the topography of the underlying bedrock and reveal the presence of several continuous reflectors dipping down-slope. Observations based on drilling and a single test pit indicate that the snowfield is 6.2 m thick and that it contains discontinuous lenses or layers of ice from 2 to 30 mm in thickness. Plant material from the depth of 4.05 m in the drilling core yielded a radiocarbon age of 35 years, while variations in the size of lichens growing at the edge of the snowfield indicated that the snowfield was of considerably greater extent some 100 to 150 years ago. The results suggest that the snowfield has been stable for a relatively long period but the “residence time” of snow in the snowfield is rather short, presumably less than 100 years and possibly only a few decades. Percussion drilling on the Ridnitvsohkka summit plateau, situating 1290 m a.s.l., revealed that the till was frozen at the depth of 1.9 m at the end of July 1993. Discovery of frozen till shows that frozen ground can locally survive from one season to the next, while the extent of the permanent snowfield and vegetation-free patterned ground suggest that the conditions favourable for permafrost might have existed over wider areas. Article in Journal/Newspaper Ice permafrost Lapland Directory of Open Access Journals: DOAJ Articles Bulletin of the Geological Society of Finland 72 1-2 47 56 |
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topic |
periglacial features snow firn permafrost till drilling Ridnitvsohkka Lapland Finland Geology QE1-996.5 |
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periglacial features snow firn permafrost till drilling Ridnitvsohkka Lapland Finland Geology QE1-996.5 H. Hirvas P. Lintinen P. Kosloff An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland |
topic_facet |
periglacial features snow firn permafrost till drilling Ridnitvsohkka Lapland Finland Geology QE1-996.5 |
description |
An area of permanent snow and frozen ground was studied at the end of summer seasons during the years 1990–1993 near the summit of Ridnitvsohkka fell, which at 1317 m a.s.l. is the second highest peak in Finland. The eastern flank of Ridnitvsohkka has the most extensive area of permanent snow (3 km2) in Finland, while the summit region represents the highest single area of basal till devoid of vegetation cover and displaying patterned ground features. The ground penetrating radar results show that the form of the snowfield does not conform to the topography of the underlying bedrock and reveal the presence of several continuous reflectors dipping down-slope. Observations based on drilling and a single test pit indicate that the snowfield is 6.2 m thick and that it contains discontinuous lenses or layers of ice from 2 to 30 mm in thickness. Plant material from the depth of 4.05 m in the drilling core yielded a radiocarbon age of 35 years, while variations in the size of lichens growing at the edge of the snowfield indicated that the snowfield was of considerably greater extent some 100 to 150 years ago. The results suggest that the snowfield has been stable for a relatively long period but the “residence time” of snow in the snowfield is rather short, presumably less than 100 years and possibly only a few decades. Percussion drilling on the Ridnitvsohkka summit plateau, situating 1290 m a.s.l., revealed that the till was frozen at the depth of 1.9 m at the end of July 1993. Discovery of frozen till shows that frozen ground can locally survive from one season to the next, while the extent of the permanent snowfield and vegetation-free patterned ground suggest that the conditions favourable for permafrost might have existed over wider areas. |
format |
Article in Journal/Newspaper |
author |
H. Hirvas P. Lintinen P. Kosloff |
author_facet |
H. Hirvas P. Lintinen P. Kosloff |
author_sort |
H. Hirvas |
title |
An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland |
title_short |
An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland |
title_full |
An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland |
title_fullStr |
An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland |
title_full_unstemmed |
An extensive permanent snowfield and the possible occurrence of permafrost in till in the Ridnitšohkka area, Finnish Lapland |
title_sort |
extensive permanent snowfield and the possible occurrence of permafrost in till in the ridnitšohkka area, finnish lapland |
publisher |
Geological Society of Finland |
publishDate |
2000 |
url |
https://doi.org/10.17741/bgsf/72.1-2.003 https://doaj.org/article/dcd101c747dd47639f90c9bf612442e4 |
genre |
Ice permafrost Lapland |
genre_facet |
Ice permafrost Lapland |
op_source |
Bulletin of the Geological Society of Finland, Vol 72, Iss 1-2, Pp 47-56 (2000) |
op_relation |
http://www.geologinenseura.fi/bulletin/Volume72/Hirvasetal.pdf https://doaj.org/toc/0367-5211 https://doaj.org/toc/1799-4632 doi:10.17741/bgsf/72.1-2.003 0367-5211 1799-4632 https://doaj.org/article/dcd101c747dd47639f90c9bf612442e4 |
op_doi |
https://doi.org/10.17741/bgsf/72.1-2.003 |
container_title |
Bulletin of the Geological Society of Finland |
container_volume |
72 |
container_issue |
1-2 |
container_start_page |
47 |
op_container_end_page |
56 |
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1766027930028212224 |