| Title | Spatiotemporal impacts of wildfire and climate warming on permafrost across a subarctic region, Canada |
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| Author | Zhang, Y ; Wolfe,
S A; Morse, P D; Olthof, I; Fraser, R H |
| Source | Journal of Geophysical Research, Earth Surface vol. 120, issue 11, 2015 p. 2338-2356, https://doi.org/10.1002/2015JF003679  Open Access |
| Image |  |
| Year | 2015 |
| Alt Series | Earth Sciences Sector, Contribution Series 20150203 |
| Publisher | Wiley-Blackwell |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Northwest Territories |
| NTS | 85I; 85J; 85O; 85P |
| Area | Yellowknife |
| Lat/Long WENS | -116.0000 -111.0000 64.2500 62.2500 |
| Subjects | geophysics; surficial geology/geomorphology; environmental geology; Nature and Environment; glacial deposits; permafrost; freezing ground; ground ice; terrain sensitivity; peatlands; fires; climate;
climatic fluctuations; climate, arctic |
| Illustrations | location maps; photographs; satellite images; tables; histograms; plots |
| Program | Climate Change Geoscience Land-based Infrastructure |
| Released | 2015 11 23 |
| Abstract | Field observations show significant impacts of wildfires on active layer thickness and ground temperatures. However, the importance of fires to permafrost conditions at regional scales remains unclear,
especially with climate warming. This study evaluated the regional impacts of fire on permafrost with climate change from 1942 to 2100 using a process-based model in a large subarctic region in the Northwest Territories, Canada. Climate warming is
shown to be the dominant factor for permafrost reduction. The warming trend of climate reduces permafrost extent in this region from 67% at present to 2% by 2100. For burned areas, fire increases the reduction of permafrost extent by up to 9% on
average, with up to 16% for forest, 10% for tundra and bogs, and 4% for fens. Fire accelerates permafrost disappearance by 5?years on average. The effects of fire on active layer thickness and permafrost extent are much larger in forest areas than in
tundra, bogs, and fens. Since active layer is thicker after a fire and cannot recover in most of the areas, the fire effects on active layer are widespread. On average, fires thickens active layer by about 0.5?m. The fire effects on active layer
increased significantly after 1990 due to climate warming. |
| Summary | (Plain Language Summary, not published)
Site observations show significant impacts of wildfires on summer thaw depths and ground temperatures. However, the importance of fires to permafrost
conditions at regional scales remains unclear, especially with climate warming. This study assessed regional impacts of fire and climate change during 1942-2100 using a process-based model for a large subarctic region in the Northwest Territories,
Canada. Climate warming is shown to be the dominant factor for permafrost reduction. The warming trend of climate reduces permafrost extent in this region from 67% at present to 2% by 2100. For burned areas, fire increases the reduction of permafrost
extent by up to 9% on average. The effects of fire on active-layer thickness and permafrost extent are much larger in forest areas than in tundra, bogs and fens. Since active layer is thicker after a fire and cannot recover in most of the areas, the
fire effects on active layer are widespread. |
| GEOSCAN ID | 296905 |
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