| Resource Name |
Multi-decadal degradation and persistence of permafrost in the Alasak Highway corridor, northwest Canada |
| Unique File Number |
368 |
| Information Type |
applied Research |
| Surface Water |
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| Aquatic Ecosystem |
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| Groundwater |
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| Groundwater & Surface Water |
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| Management for Natural & Industrial Hazards |
A |
| Strengths |
compares changes in permafrost extent and properties over ~ 40 years along Alaska Highway due to effects of warming climate |
| Limitations |
limited spatial extent |
| Challenges |
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| Outstanding Research Questions |
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| Outstanding Research Questions |
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| Information Subtype |
permafrost |
| Organization |
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| Resource Name |
James, M et al. 2013. Multi-decadal degradation and persistence of permafrost in the Alaska Highway corridor, northwest Canada. Environmental Research Letters 8.doi:10.1088/1748-9326/8/4/045013 |
| Resource Purpose |
Changes in permafrost distribution in the southern discontinuous zone were evaluated by repeating a 1964 survey through part of the Alaska Highway corridor (56° N–61° N) in northwest Canada. A total of 55 sites from the original survey in northern British Columbia and southern Yukon were located using archival maps and photographs. Probing for frozen ground, manual excavations, air and ground temperature monitoring, borehole drilling and geophysical techniques were used to gather information on present-day permafrost and climatic conditions. Mean annual air temperatures have increased by 1.5–2.0 ° C since the mid-1970s and significant degradation of permafrost has occurred. Almost half of the permafrost sites along the entire transect which exhibited permafrost in 1964 do so no longer. This change is especially evident in the south where two-thirds of the formerly permafrost sites have thawed and the limit of permafrost appears to have shifted northward. The permafrost that persists is patchy, generally less than 15 m thick, has mean annual surface temperatures >0 ° C, mean ground temperatures between −0.5 and 0 ° C, is in peat or beneath a thick organic mat, and appears to have a thicker active layer than in 1964. Its persistence may relate to the latent heat requirements of thawing permafrost or to the large thermal offset of organic soils. The study demonstrates that degradation of permafrost has occurred in the margins of its distribution in the last few decades, a trend that is expected to continue as the climate warms. |
| Type of Information |
article |
| How does this help decision making? |
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| Program Status |
complete |
| NE Coverage |
ne BC specific |
| Drinking Water |
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| Ecosystem |
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| Fish |
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| Groundwater |
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| Public Safety |
y |
| SW Quality |
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| SW Quantity |
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| Link |
doi:10.1088/1748-9326/8/4/045013 |
| Text Query |
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| Google Earth |
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| iMap Path Link |
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| Spatial Metadata |
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| Map |
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| Contact Email |
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