Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec
Recent land cover changes in the Umiujaq region of northern Québec, Canada, have been quantified in order to estimate changes in the extent of discontinuous permafrost that strongly affect the forest‐tundra ecotone. Changes in the areas covered by different vegetation types, thermokarst lakes and de...
Published in: | Permafrost and Periglacial Processes |
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Online Access: | https://doi.org/10.1002/ppp.1839 |
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ftrepec:oai:RePEc:wly:perpro:v:26:y:2015:i:2:p:129-141 2023-05-15T13:03:21+02:00 Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec Inga Beck Ralf Ludwig Monique Bernier Esther Lévesque Julia Boike https://doi.org/10.1002/ppp.1839 unknown https://doi.org/10.1002/ppp.1839 article ftrepec https://doi.org/10.1002/ppp.1839 2020-12-04T13:31:25Z Recent land cover changes in the Umiujaq region of northern Québec, Canada, have been quantified in order to estimate changes in the extent of discontinuous permafrost that strongly affect the forest‐tundra ecotone. Changes in the areas covered by different vegetation types, thermokarst lakes and degradation of lithalsas have been investigated over an area of 60 km2, extending from widespread discontinuous permafrost in the north to areas of scattered permafrost in the south, and from Hudson Bay in the west to the Lac Guillaume‐Delisle graben 10 km further east. We used high‐resolution remote sensing images (QuickBird 2004, GeoEye 2009) and four Landsat scenes (1986, 1990, 2001, 2008) as well as ground‐based data (vegetation, active layer thickness, snow parameters) collected between 2009 and 2011. Two change detection methods applied to estimate the land cover changes between 1986 and 2009 showed an overall increase in vegetation extent between 1986 and 2009, and a 21 per cent increase in tall vegetation (spruce and tall shrubs) between 2004 and 2009 at the expense of low vegetation (lichens, prostrate shrubs, herbaceous vegetation). Thermokarst lakes and lithalsas in ten sub‐areas were mapped manually from satellite imagery. The area covered by water decreased by 24 per cent between 2004 and 2009, often due to vegetation colonising the margins of lakes, and 93 of the observed lakes disappeared completely over that period. The area covered by lithalsas declined by 6 per cent. Our results demonstrate the viability of using high‐resolution satellite imagery to detect changes in the land surface that can serve as indicators of permafrost degradation in the sub‐Arctic. Copyright © 2015 John Wiley & Sons, Ltd. Article in Journal/Newspaper Active layer thickness Arctic Hudson Bay permafrost Thermokarst Tundra Umiujaq RePEc (Research Papers in Economics) Arctic Canada Guillaume ENVELOPE(70.150,70.150,-49.350,-49.350) Hudson Hudson Bay Lac Guillaume-Delisle ENVELOPE(-76.294,-76.294,56.249,56.249) Umiujaq ENVELOPE(-76.549,-76.549,56.553,56.553) Permafrost and Periglacial Processes 26 2 129 141 |
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Open Polar |
collection |
RePEc (Research Papers in Economics) |
op_collection_id |
ftrepec |
language |
unknown |
description |
Recent land cover changes in the Umiujaq region of northern Québec, Canada, have been quantified in order to estimate changes in the extent of discontinuous permafrost that strongly affect the forest‐tundra ecotone. Changes in the areas covered by different vegetation types, thermokarst lakes and degradation of lithalsas have been investigated over an area of 60 km2, extending from widespread discontinuous permafrost in the north to areas of scattered permafrost in the south, and from Hudson Bay in the west to the Lac Guillaume‐Delisle graben 10 km further east. We used high‐resolution remote sensing images (QuickBird 2004, GeoEye 2009) and four Landsat scenes (1986, 1990, 2001, 2008) as well as ground‐based data (vegetation, active layer thickness, snow parameters) collected between 2009 and 2011. Two change detection methods applied to estimate the land cover changes between 1986 and 2009 showed an overall increase in vegetation extent between 1986 and 2009, and a 21 per cent increase in tall vegetation (spruce and tall shrubs) between 2004 and 2009 at the expense of low vegetation (lichens, prostrate shrubs, herbaceous vegetation). Thermokarst lakes and lithalsas in ten sub‐areas were mapped manually from satellite imagery. The area covered by water decreased by 24 per cent between 2004 and 2009, often due to vegetation colonising the margins of lakes, and 93 of the observed lakes disappeared completely over that period. The area covered by lithalsas declined by 6 per cent. Our results demonstrate the viability of using high‐resolution satellite imagery to detect changes in the land surface that can serve as indicators of permafrost degradation in the sub‐Arctic. Copyright © 2015 John Wiley & Sons, Ltd. |
format |
Article in Journal/Newspaper |
author |
Inga Beck Ralf Ludwig Monique Bernier Esther Lévesque Julia Boike |
spellingShingle |
Inga Beck Ralf Ludwig Monique Bernier Esther Lévesque Julia Boike Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec |
author_facet |
Inga Beck Ralf Ludwig Monique Bernier Esther Lévesque Julia Boike |
author_sort |
Inga Beck |
title |
Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec |
title_short |
Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec |
title_full |
Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec |
title_fullStr |
Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec |
title_full_unstemmed |
Assessing Permafrost Degradation and Land Cover Changes (1986–2009) using Remote Sensing Data over Umiujaq, Sub‐Arctic Québec |
title_sort |
assessing permafrost degradation and land cover changes (1986–2009) using remote sensing data over umiujaq, sub‐arctic québec |
url |
https://doi.org/10.1002/ppp.1839 |
long_lat |
ENVELOPE(70.150,70.150,-49.350,-49.350) ENVELOPE(-76.294,-76.294,56.249,56.249) ENVELOPE(-76.549,-76.549,56.553,56.553) |
geographic |
Arctic Canada Guillaume Hudson Hudson Bay Lac Guillaume-Delisle Umiujaq |
geographic_facet |
Arctic Canada Guillaume Hudson Hudson Bay Lac Guillaume-Delisle Umiujaq |
genre |
Active layer thickness Arctic Hudson Bay permafrost Thermokarst Tundra Umiujaq |
genre_facet |
Active layer thickness Arctic Hudson Bay permafrost Thermokarst Tundra Umiujaq |
op_relation |
https://doi.org/10.1002/ppp.1839 |
op_doi |
https://doi.org/10.1002/ppp.1839 |
container_title |
Permafrost and Periglacial Processes |
container_volume |
26 |
container_issue |
2 |
container_start_page |
129 |
op_container_end_page |
141 |
_version_ |
1766334527287853056 |