Title | Permafrost and peatland evolution in the northern Hudson Bay Lowlands, Manitoba |
| |
Author | Dyke, L D; Sladen, W E |
Source | Arctic vol. 63, no. 4, 2010 p. 429-441, https://doi.org/10.14430/arctic3332 Open Access |
Image |  |
Year | 2010 |
Alt Series | Earth Sciences Sector, Contribution Series 20090273 |
Publisher | The Arctic Institute of North America |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Province | Manitoba |
NTS | 54F; 54K |
Area | Northern Hudson Bay Lowland; Wapusk National Park |
Lat/Long WENS | -94.0000 -92.5000 59.0000 57.0000 |
Subjects | surficial geology/geomorphology; Nature and Environment; permafrost; freezing ground; ground ice; ground temperatures; fens; peat; peatlands; peat analyses |
Illustrations | location maps; photographs; cross-sections; tables; graphs; plots |
Program | Climate Change Geoscience |
Released | 2010 12 03 |
Abstract | The northern Hudson Bay lowland includes the largest area of frozen peat plateau bog in Canada. Polar bear denning habitat, caribou forage, carbon storage, and wetland drainage control provided by peat
plateaus will be affected if post-Little Ice Age warming continues. Mapping and thermal modeling of frozen peat plateau stability indicate that permafrost peatlands are stable at a mean annual air temperature as warm as -3.5°C. In the peat plateaus
of the northern lowland, permafrost can be absent at the peat plateau margins where peat plateaus border fens or lakes. Here, insulating snow accumulations permit thawed conditions at mean annual air temperatures colder than -3.5°C. Continued warming
will result in expansion of thawed zones, subsidence at plateau margins, and even collapse of plateau surfaces, resulting in conversion to fen. This process has already occurred across north-central Manitoba, Saskatchewan, and Alberta since the end
of the Little Ice Age, and there are signs that it is extending into the northern Hudson Bay lowland. Wave erosion of subsiding plateau borders at lake shorelines is also resulting in loss of peat plateau bog. |
GEOSCAN ID | 248153 |
|
|