Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends
Climate warming is more pronounced in the Arctic than in other parts of the world. This warming affects the terrestrial cryosphere including permafrost with consequences ranging from societal impacts to changes in hydrology and feedbacks in the climate system such as those imposed by changing greenh...
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ftulundlup:oai:lup.lub.lu.se:d9061f15-b3ab-408e-a313-a8d20d0f7abc 2023-05-15T13:02:58+02:00 Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends Johansson, Margareta 2009 application/pdf https://lup.lub.lu.se/record/1288754 https://portal.research.lu.se/files/5252499/1288755.pdf eng eng https://lup.lub.lu.se/record/1288754 https://portal.research.lu.se/files/5252499/1288755.pdf info:eu-repo/semantics/openAccess Meddelande från Lunds Universitets Geografiska Institution; 180 (2009) ISSN: 0346-6787 Physical Geography thesis/doccomp info:eu-repo/semantics/doctoralThesis text 2009 ftulundlup 2023-02-01T23:31:13Z Climate warming is more pronounced in the Arctic than in other parts of the world. This warming affects the terrestrial cryosphere including permafrost with consequences ranging from societal impacts to changes in hydrology and feedbacks in the climate system such as those imposed by changing greenhouse gas exchanges. Permafrost dynamics in a marginal zone for its very existence is in this context of outmost importance as it represents a very sensitive environment where changes may appear first. The main objective of this project was to understand the current status of such sensitive lowland permafrost in the Torneträsk area, sub-arctic Sweden and to explore its development over the past 1000 yrs in relation to various environmental drivers of change. Monitoring of permafrost temperatures and active layer thickness showed that permafrost was during the last three decades degrading in the Torneträsk catchment. Increasing ground temperatures and active layer thickness were correlated with increases in air temperatures and in some cases with snow depth. A manipulation experiment that simulated future scenarios of increases in winter precipitation showed that permafrost and vegetation were sensitive to changes in snow depth after only three years of treatment. Modelled ground temperatures showed two periods of lowland permafrost degradation during the last Century. Over the last 1000 yrs, the modelled ground temperatures at one site currently with permafrost indicated that permafrost existed throughout this period. However, this contradicts proxy data from the area that suggests that permafrost formation occurred during the Little Ice Age (around AD1300). This study has improved our understanding of current and past dynamics of lowland sub-arctic permafrost in northernmost Sweden. The presence or absence of permafrost in the Torneträsk catchment is determined by many factors, but air temperatures, snow depth, vegetation and soil type are the most important. A major conclusion of the study is that the strength of the ... Doctoral or Postdoctoral Thesis Active layer thickness Arctic Ice Northern Sweden permafrost Lund University Publications (LUP) Arctic Torneträsk ENVELOPE(18.861,18.861,68.392,68.392) |
institution |
Open Polar |
collection |
Lund University Publications (LUP) |
op_collection_id |
ftulundlup |
language |
English |
topic |
Physical Geography |
spellingShingle |
Physical Geography Johansson, Margareta Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends |
topic_facet |
Physical Geography |
description |
Climate warming is more pronounced in the Arctic than in other parts of the world. This warming affects the terrestrial cryosphere including permafrost with consequences ranging from societal impacts to changes in hydrology and feedbacks in the climate system such as those imposed by changing greenhouse gas exchanges. Permafrost dynamics in a marginal zone for its very existence is in this context of outmost importance as it represents a very sensitive environment where changes may appear first. The main objective of this project was to understand the current status of such sensitive lowland permafrost in the Torneträsk area, sub-arctic Sweden and to explore its development over the past 1000 yrs in relation to various environmental drivers of change. Monitoring of permafrost temperatures and active layer thickness showed that permafrost was during the last three decades degrading in the Torneträsk catchment. Increasing ground temperatures and active layer thickness were correlated with increases in air temperatures and in some cases with snow depth. A manipulation experiment that simulated future scenarios of increases in winter precipitation showed that permafrost and vegetation were sensitive to changes in snow depth after only three years of treatment. Modelled ground temperatures showed two periods of lowland permafrost degradation during the last Century. Over the last 1000 yrs, the modelled ground temperatures at one site currently with permafrost indicated that permafrost existed throughout this period. However, this contradicts proxy data from the area that suggests that permafrost formation occurred during the Little Ice Age (around AD1300). This study has improved our understanding of current and past dynamics of lowland sub-arctic permafrost in northernmost Sweden. The presence or absence of permafrost in the Torneträsk catchment is determined by many factors, but air temperatures, snow depth, vegetation and soil type are the most important. A major conclusion of the study is that the strength of the ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Johansson, Margareta |
author_facet |
Johansson, Margareta |
author_sort |
Johansson, Margareta |
title |
Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends |
title_short |
Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends |
title_full |
Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends |
title_fullStr |
Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends |
title_full_unstemmed |
Changing Lowland Permafrost in Northern Sweden: Multiple Drivers of Past and Future Trends |
title_sort |
changing lowland permafrost in northern sweden: multiple drivers of past and future trends |
publishDate |
2009 |
url |
https://lup.lub.lu.se/record/1288754 https://portal.research.lu.se/files/5252499/1288755.pdf |
long_lat |
ENVELOPE(18.861,18.861,68.392,68.392) |
geographic |
Arctic Torneträsk |
geographic_facet |
Arctic Torneträsk |
genre |
Active layer thickness Arctic Ice Northern Sweden permafrost |
genre_facet |
Active layer thickness Arctic Ice Northern Sweden permafrost |
op_source |
Meddelande från Lunds Universitets Geografiska Institution; 180 (2009) ISSN: 0346-6787 |
op_relation |
https://lup.lub.lu.se/record/1288754 https://portal.research.lu.se/files/5252499/1288755.pdf |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766325299905036288 |