| Title | Distribution and morphometry of pingos, western Canadian Arctic, Northwest Territories, Canada |
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| Author | Wolfe, S A ;
Morse, P D; Parker, R |
| Source | Geomorphology 108694, 2023 p. 1-12, https://doi.org/10.1016/j.geomorph.2023.108694 |
| Image |  |
| Year | 2023 |
| Alt Series | Natural Resources Canada, Contribution Series 20220351 |
| Publisher | Elsevier |
| Document | serial |
| Lang. | English |
| Media | paper; digital; on-line |
| Related | NRCan photo(s) in this
publication |
| File format | pdf; html |
| Province | Northwest Territories |
| NTS | 107A; 107B; 107C; 107D; 107E; 107F; 117A; 117D; 117E |
| Lat/Long WENS | -136.4294 -128.5419 70.3164 68.0331 |
| Subjects | Science and Technology; general geology; permafrost; pingos |
| Illustrations | photographs; diagrams; location maps |
| Program | Climate Change
Geoscience Permafrost |
| Released | 2023 04 08 |
| Abstract | Pingos of the western Canadian Arctic (WCA) coastal plain are among the most abundant and well-studied in the northern hemisphere. However, the abundance and morphometric variation of these pingos has
not been quantitatively examined with respect to surficial and physiographic settings, likely because they have never been systematically catalogued with precision. We assess the distribution and morphology of pingos in the WCA using the High
Resolution Digital Elevation Model (HRDEM) and demonstrate how this population compares to others in the Arctic, and how it varies in relation to surficial and physiographic settings. Of the 2363 pingos identified in the WCA (900 more than previous
estimates), relief ranges from a few 10s of centimetres to 46.7m for Ibyuk Pingo, which is the archetype of closed-system (hydrostatic) pingos in the region. Nearly 18% (272) are taller than 10m, although about 35% of the pingos (830) are <2m tall,
which is the minimum height limit of most other studies. Using this minimum cut-off to compare populations, the mean height of WCA pingos >2m (n=1533) is 6.5m, which is greater than other lowland pingos in the Arctic. WCA pingos are about 10% larger
in radius than pingos in North Alaska but have comparable mean slopes. Nevertheless, about 72% of WCA pingos > 2m tall are "high-slope" pingos with a mean slope of 5° or greater. Within the WCA, 95% of all pingos occur within the Tuktoyaktuk Lowlands
in relation to the distribution of underlying Pleistocene sands, specifically the extent of braidplain deposits from the paleo-Peel and Anderson rivers known as the Kidluit Formation (Marine Isotope Stage 3). However, the spatial density of pingos
within the Tuktoyaktuk Lowlands varies with physiography, and the highest densities relate to ice-rich, topographically-complex terrains that have a history of glaciation and thermokarst. In contrast, pingos within the modern Mackenzie Delta, where
the low-lying, Holocene-age terrain is not amenable to lake drainage that promotes closed-system pingo formation, have a low density (5% of total population) and are smaller. Nearly 30% of WCA pingos reside at <5m asl. Consequently, ongoing relative
sea level rise and the effects on coastal change are likely to erode some pingos within the current population but may also trigger lake drainage and formation of new pingos. |
| Summary | (Plain Language Summary, not published)
We mapped and measured the distribution and characteristics of pingos in the Tuktoyaktuk Coastlands, Northwest Territories Canada. There are 2363 pingos
in the region. This is the highest density of pingos in the northern hemisphere. The average size of pingos is taller and larger than pingos in other areas of the arctic. The distribution of pingos is related to the extent of underlying fluvial sands
and to landscape complexity. Areas of interconnected drainage have higher abundances of pingos than areas of small closed-lake basins. |
| GEOSCAN ID | 330887 |
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