| Title | New information on permafrost thermal state in the Alaska Highway Corridor, Yukon |
| |
| Author | Smith, S ;
Lewkowicz, A G; Ednie, M; Bevington, A; Blais-Stevens, A;
Bonnaventure, P |
| Source | Arctic Change 2014, poster abstracts; 2014 p. 185 |
| Links | Online - En ligne
|
| Image |  |
| Year | 2014 |
| Alt Series | Earth Sciences Sector, Contribution Series 20140230 |
| Meeting | Arctic Change 2014; Ottawa; CA; December 8-12, 2014 |
| Document | book |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Yukon |
| NTS | 105D/13; 105D/14; 115A/13; 115A/14; 115A/15; 115A/16; 115B/16; 115F/15; 115F/16; 115G/01; 115G/02; 115G/05; 115G/06; 115G/07; 115G/11; 115G/12; 115G/13; 115K/02; 115K/07; 115K/10 |
| Area | Alaska Highway Corridor |
| Lat/Long WENS | -141.0000 -134.0000 62.7500 60.7500 |
| Subjects | surficial geology/geomorphology; engineering geology; Nature and Environment; permafrost; freezing ground; ground ice; ground temperatures; thermal analyses; pipeline feasibility studies; pipelines;
climate; Cenozoic; Quaternary |
| Program | Climate
Change Geoscience Risk Analysis |
| Released | 2014 01 01 |
| Abstract | The Alaska Highway Corridor traverses the discontinuous permafrost zone of the southern Yukon. Permafrost characteristics were investigated in the corridor over 30 years ago to support a pipeline
proposal but little information is available on current ground thermal conditions. Air temperatures in the region have increased 0.4-0.5°C per decade since the 1970s and recent studies in the corridor indicate that thawing of permafrost has occurred
over the last four decades (e.g. James et al. 2013). Recent proposals for construction and operation of a natural gas pipeline and the need to develop climate change adaptation strategies for existing highway infrastructure has stimulated the
acquisition of updated information on permafrost conditions.
Between 2011 and 2013, nineteen boreholes up to 10 m deep were instrumented with temperature cables in the section of the corridor west of Whitehorse in order to characterize the
ground thermal conditions. These boreholes complement those instrumented during the International Polar Year elsewhere in the central and southern Yukon.
The ground thermal data collected indicates that permafrost is generally warm (above
-1.5°C) in this section of the corridor. However, colder permafrost (-3°C) was found in the immediate vicinity of the Alaska border in an area predicted by Bonnaventure et al. (2012) to be continuous permafrost. Data records are too short to
determine if there is any trend in permafrost temperatures. However, a comparison of recent ground temperatures with those collected by the Geological Survey of Canada in the late 1970s indicates that warming of permafrost has occurred of a similar
magnitude as that observed elsewhere in northwestern Canada (Dugay et al. in prep).
The ground thermal data collected from these new monitoring sites have been compiled into a digital database along with data obtained from other instrumented
boreholes in the central and southern Yukon. These data facilitate a better understanding of regional permafrost conditions and support improved assessments of terrain sensitivity including models of landslide susceptibiltiy. The publicly available
data can also be utilized for climate change adaptation planning and to support infrastructure design in the region. |
| Summary | (Plain Language Summary, not published)
Instrumented field sites established 2011-13 along the Alaska Highway corridor between Whitehorse and the Alaska border, provide new information on
current permafrost conditions. This information is required for terrain sensitivity assessments and planning northern development (eg. pipeline, highway) to ensure infrastructure and environmental integrity. Results indicated that permafrost in this
section of the corridor is generally warm (temperatures above -1.5°C but is as cold as -3°C near the Alaska border. Comparison with ground temperatures measured in the late 1970s indicates that permafrost temperatures may have increased over the last
30 years. |
| GEOSCAN ID | 295214 |
|
|