Borehole and near-surface ground temperatures in northeastern Canada

Allard, Michel; Sarrazin, Denis; L'Hérault, E.

doi:10.5885/45291sl-34f28a9491014afd

Cited by 19 publications

(8 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Permafrost thickness was estimated to be at least 200-400 m based on shallow ground temperature measurements on the island (Moorman, 2003). On average, the active-layer thickness varies between 0.3 and 0.7 m in peaty and silty soils to more than 1 m in drained unvegetated sands and gravels (Allard et al, 2020). Thawing and freezing indices averaged (1981-2010 period) 473 degree days above 0 • C and 5736 degree days below 0 • C, respectively (Environment Canada, 2021).…”

Section: Study Areamentioning

confidence: 99%

“…Ice-cored moraine landscapes may lose their buried ice cores thousands to millions of years after the major glacial retreat (Bibby et al, 2016;Coulombe et al, 2019;Lacelle et al, 2007;Swanger, 2017). The persistence of thick beds of buried Pleistocene glacier ice in contemporary permafrost environments indicates that deglaciation is still incomplete (Astakhov and Isayeva, 1988;Everest and Bradwell, 2003;Kaplanskaya and Tarnogradskiy, 1986;Lenz et al, 2013). The broad distribution and the substantial amount of ground ice in glaciated permafrost landscapes make it highly vulnerable to disturbances, such as thermokarst, under the ongoing climate warming Segal et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

“…The broad distribution and the substantial amount of ground ice in glaciated permafrost landscapes make it highly vulnerable to disturbances, such as thermokarst, under the ongoing climate warming Segal et al, 2016). As such, some of these landscapes are now entering a second phase of landscape evolution (Astakhov and Isayeva, 1988;Everest and Bradwell, 2003). For example, on hillslopes, the thawing of permafrost terrain underlain by remnants of glacial ice triggered mass wasting processes, such as retrogressive thaw slump and active layer detachment slides (Kokelj et al, 2017;Rudy et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

“…It is generally recognized that numerous Arctic lakes were formed during deglaciation in depressions left by in situ melting of stagnant blocks of glacier ice (also named kettle lakes or postglacial lakes). However, very few studies have linked lake inception to the thawing of sediments containing glacier ice that had been buried and preserved in permafrost for decades to millennia (Henriksen et al, 2003;Worsley, 1999;Astakhov and Isayeva, 1988). As a result, there is little information on the spatial distribution and abundance and evolution of these glacial thermokarst lakes in modern paraglacial and periglacial environments.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Contrasted geomorphological and limnological properties of thermokarst lakes formed in buried glacier ice and ice-wedge polygon terrain

et al. 2022

View full text Add to dashboard Cite

Abstract. In formerly glaciated permafrost regions, extensive areas are still underlain by a considerable amount of glacier ice buried by glacigenic sediments. It is expected that large parts of glacier ice buried in the permafrost will melt in the near future, although the intensity and timing will depend on local terrain conditions and the magnitude and rate of future climate trends in different Arctic regions. The impact of these ice bodies on landscape evolution remains uncertain since the extent and volume of undisturbed relict glacier ice are unknown. These remnants of glacier ice buried and preserved in the permafrost contribute to the high spatial variability in ground ice condition of these landscapes, leading to the formation of lakes with diverse origins and morphometric and limnological properties. This study focuses on thermokarst lake initiation and development in response to varying ground ice conditions in a glacial valley on Bylot Island (Nunavut). We studied a lake-rich area using lake sediment cores, detailed bathymetric data, remotely sensed data and observations of buried glacier ice exposures. Our results suggest that initiation of thermokarst lakes in the valley was triggered from the melting of either buried glacier ice or intrasedimental ice and ice wedges. Over time, all lakes enlarged through thermal and mechanical shoreline erosion, as well as vertically through thaw consolidation and subsidence. Some of them coalesced with neighbouring water bodies to develop larger lakes. These glacial thermokarst lakes formed in buried glacier ice now evolve as “classic” thermokarst lakes that expand in area and volume as a result of the melting of intrasedimental ground ice in the surrounding material and the underlying glaciofluvial and till material. It is expected that the deepening of thaw bulbs (taliks) and the enlargement of Arctic lakes in response to global warming will reach undisturbed buried glacier ice where it is still present, which in turn will substantially alter lake bathymetry, geochemistry and greenhouse gas emissions from Arctic lowlands.

show abstract

Section: Study Areamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Contrasted geomorphological and limnological properties of thermokarst lakes formed in buried glacier ice and ice-wedge polygon terrain

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Comprehensive permafrost geotechnical characterization and mapping aim at providing contractors, communities and regional governments with the scientific support they need to adapt and develop on permafrost terrain (Allard et al, 2020). One of the specific goals of the project is to help promotors select properly adapted foundations for different types and functions of buildings over variable permafrost terrain conditions.…”

Section: Introductionmentioning

confidence: 99%

Facing the challenge of permafrost thaw in Nunavik communities: innovative integrated methodology, lessons learnt, and recommendations to stakeholders

et al. 2023

View full text Add to dashboard Cite

In order to support climate change adaptation in the communities of Nunavik, an innovative multi-technique approach to map permafrost conditions and assess risks of geohazards at the community-scale level was applied. Four maps were produced for each community: 1- a surficial geology map, 2- a map of permafrost conditions based on ground-ice content and depth to bedrock, 3- a map of potential for construction and 4- a geohazard risk assessment map. Local ground temperature data from thermistor cables were used to calibrate one-dimensional numerical models to estimate future permafrost temperature changes and probable rates of degradation in different environmental settings within the communities and under different climate change scenarios for the 2019-2100 period. Throughout this project, abundant consultations were held in communities and with stakeholders to better understand their concerns and to provide pragmatic recommendations for improving construction methods and land-use planning to face the challenges of permafrost thaw. Specific recommendations were made to the higher levels of government for improving construction practices. Inuit aspirations, culture and leadership remain keys in how to integrate permafrost geotechnical knowledge in planning a safe future for the communities.

show abstract

Uncertainties in coupled regional Arctic climate simulations associated with the used land surface model

et al. 2017

View full text Add to dashboard Cite

Permafrost is one of the most important components of Arctic land. Regional atmosphere‐snow‐permafrost interactions can be best studied with Regional Climate Models (RCMs) due to their higher horizontal resolution compared to global climate models. The development of Arctic RCMs with sophisticated land models is therefore very important. Comparing RCMs with different land surface model (LSM) components then allows the quantification of the uncertainties associated with the LSM. This study analyzes two simulations of coupled atmosphere‐land RCMs over the Arctic, which differ only in their land component, while the atmospheric model component is the same. Specifically, we examine HIRHAM5‐CLM4 (HIRHAM5 coupled with the sophisticated land model CLM4) and HIRHAM5 (HIRHAM5 coupled with the simpler land model of ECHAM5). We discuss the two models' abilities to represent observations on permafrost‐like permafrost extent, active layer thickness (ALT), and soil temperature profiles, as well as on the representation of the Arctic atmosphere, based on simulations over 1979–2014. In comparison to HIRHAM5, HIRHAM5‐CLM4 significantly reduces the simulated bias in ALT and winter soil temperatures. We find that the simulation of soil temperature and subsequently ALT is sensitive to soil thermal and hydraulic parameter representation in the models. The simulation of permafrost extent is sensitive to the initial soil temperature state in the models. Both HIRHAM5 and HIRHAM5‐CLM4 do similarly well in modeling the Arctic 2 m air temperature and atmospheric circulation. Changing the land model impacts the 2 m air temperature significantly over land and the atmospheric circulation predominantly over the Arctic Ocean, associated with changes in baroclinic cyclones.

show abstract

Borehole and near-surface ground temperatures in northeastern Canada

Cited by 19 publications

References 8 publications

Contrasted geomorphological and limnological properties of thermokarst lakes formed in buried glacier ice and ice-wedge polygon terrain

Contrasted geomorphological and limnological properties of thermokarst lakes formed in buried glacier ice and ice-wedge polygon terrain

Facing the challenge of permafrost thaw in Nunavik communities: innovative integrated methodology, lessons learnt, and recommendations to stakeholders

Uncertainties in coupled regional Arctic climate simulations associated with the used land surface model

Contact Info

Product

Resources

About