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Permafrost zonation in eastern Canada : a review of published maps

Permafrost zonation in eastern Canada : a review of published maps
Canada ; Canada de l'Est ; Cartographie ; Echelle ; Géographie physique ; Permafrost ; Périglaciaire
Although progressive improvements in data availability are apparent through time, many of the differences between maps are attributable to a lack of explicit mapping criteria, to ambiguous or conflicting definitions of permafrost continuity
and to the widely recognized lack of observational data. The term continuous permafrost should be used only with reference to small (e.g., subcontinental) geographic scales, in which zonal tendencies are apparent.

Hydrology of a perennial snowbank in the continuous permafrost zone, Melville Island, Canada

Hydrology of a perennial snowbank in the continuous permafrost zone, Melville Island, Canada
Bilan hydrologique ; Canada ; Eau de fonte ; Géographie physique ; Hydrologie ; Melville Island ; Neige ; Northwest Territories ; Permafrost ; Périglaciaire ; Zone froide

Distribution of zonal permafrost land forms with freezing and thawing indices

Distribution of zonal permafrost land forms with freezing and thawing indices
Amérique ; Asie ; Cryopédologie ; Cycle gel-dégel ; Europe ; Géographie physique ; Modelé ; Permafrost ; Périglaciaire ; Sol figuré ; Zone froide
Etude des régions où le permafrost est continu ou discontinu et différenciation des modelés qui y sont liés.

Distribution of zonal permafrost landforms with freezing and thawing indices

Distribution of zonal permafrost landforms with freezing and thawing indices
Géographie physique ; Géomorphodynamique ; Géomorphologie climatique ; Indice climatique ; Indice de dégel ; Indice de gel ; Modelé périglaciaire ; Permafrost continu ; Permafrost discontinu ; Permafrost sporadique ; Périglaciaire
In areas with under 50 cm snow cover in winter, the permafrost zones can be defined by freezing indices and thawing indices. The relationship works for Norway, Spitsbergen, Canada and Mongolia, and since these include a very wide range of thermal
environments, it is possible to trace the thermal ranges of the various active periglacial landforms. Relationships between zonal permafrost landforms and permafrost zones are emphasized.

Changing climate and permafrost distribution in the soviet Arctic

Changing climate and permafrost distribution in the soviet Arctic
Action anthropique ; Arctique ; Environnement ; Gaz carbonique ; Géographie physique ; Modèle ; Permafrost ; Prévision ; Périglaciaire ; Température ; URSS ; Variation climatique
A nonstationary model of heat and water transport in a stratified medium is used in conjunction with results from a climate-change model to estimate the severity of permafrost degradation. Results suggest that the area of continuous permafrost

Recent contributions to the study of past permafrost

Recent contributions to the study of past permafrost
Recent adavances in permafrost and periglacial research. Special issue
Bibliography ; Europe ; Ice wedge ; Inherited features ; Micromorphology ; Palaeo-environment ; Periglacial features ; Permafrost ; Pleistocene ; Quaternary ; Stratigraphy ; Thermokarst ; United States of America
continues to be preserved today as relict permafrost in the higher northern latitudes. Given that global climate warming models predict widespread thaw of permafrost in the coming century, it is surprising that little attention has been given to the insights
This paper reviews recent literature published between 2002 and 2007, concerning the previous existence of permafrost (past permafrost) that formed during the cold periods of the Pleistocene in the northern mid-latitudes. Some past permafrost
that past and relict permafrost offer as to the nature and duration of permafrost thaw.

Frozen peat mounds in continuous permafrost, northern Ungava, Quebec, Canada in Periglacial processes and landforms.

Frozen peat mounds in continuous permafrost, northern Ungava, Quebec, Canada in Periglacial processes and landforms.
Arctique ; Canada ; Coin de glace ; Cryoturbation ; Géographie physique ; Géomorphodynamique ; Palse ; Permafrost ; Périglaciaire ; Québec ; Sol polygonal ; Thermokarst ; Zone froide
The aim of this paper is to describe three types of frozen peat mounds found in the Arctic environment, and to make it clear that they should not be called palsas. The latter are the typical peat mounds which occur in the discontinuous permafrost
zone (Seppälä 1988). This distinction is thought to be necessary because research activities in the high Arctic regions are continuously increasing and there is confusion if all frozen peat mounds are described as palsas.

Climate and the limits of permafrost : a zonal analysis

Climate and the limits of permafrost : a zonal analysis
Air temperature ; Boundary ; Canada ; Climate ; Freezing ; Index ; Model ; Periglacial features ; Permafrost ; Snow ; Soil temperature ; Spatial analysis ; Thawing
This paper defines the climatic and environmental conditions that determine the limits and continuity of permafrost occurrence, in the Canadian context. The analysis utilizes a functional model that links air, surface and permafrost temperature
through seasonal surface transfer functions and subsurface thermal properties. The temperature of permafrost (TTOP) results from the interplay between the air temperature, the nival (snow) offset and the thermal offset. These offset values vary

Morphology and geotechnique of active-layer detachment failures in discontinuous and continuous permafrost, northern Canada

Morphology and geotechnique of active-layer detachment failures in discontinuous and continuous permafrost, northern Canada
Active layer ; Canada ; Ellesmere ; Geotechnics ; Landslide ; Northwest Territories ; Periglacial features ; Permafrost ; Slope dynamics
Fifty active-layer detachment failures triggered after forest fire in the discontinuous permafrost zone (central Mackenzie Valley) are compared to several hundred others caused by summer meteorological triggers in continuous permafrost (Fosheim
Peninsula, Ellesmere Island). Most failures fall into compact or elongated morphological categories. The location of the shear planes or zones in relation to the permafrost table and the degree of post-failure secondary movements (including headwall

Continentality index : its uses and limitations applied to permafrost in the Canadian Cordillera

Continentality index : its uses and limitations applied to permafrost in the Canadian Cordillera
Alberta ; Canada ; Climat ; Continentalité ; Géographie physique ; Humidité du sol ; Montagne ; Permafrost ; Périglaciaire ; Rocky Mountains ; Yukon
and landforms. The continentality index needs to be based on the lower limit of continuous permafrost to be most effective in Canada, this being defined here as regions with greater than 80 % of the area underlain by permafrost.

Piping causing thermokarst in permafrost, Ungava Peninsula, Quebec, Canada

Piping causing thermokarst in permafrost, Ungava Peninsula, Quebec, Canada
Canada ; Cold area ; Drainage ; Gully erosion ; Ice wedge ; Meltwater ; Periglacial features ; Permafrost ; Quebec ; Runoff ; Thermokarst ; Ungava
The aim of this short note is to describe an observation of rather unusual piping in an ice wedge from the continuous permafrost region in northernmost Quebec (mean annual temperature about -6°C). The hydrology of permafrost and its importance

Frequency and magnitude of active-layer detachment failures in discontinuous and continuous permafrost, Northern Canada

Frequency and magnitude of active-layer detachment failures in discontinuous and continuous permafrost, Northern Canada
Active layer ; Canada ; Climatic variation ; Cold area ; Comparative study ; Ellesmere ; Forest fire ; Mass movement ; Northwest Territories ; Periglacial features ; Permafrost ; Thawing
Peninsula, Ellesmere Island (80°N, continuous permafrost zone). The AA. focus here on the environmental triggers of detachment failure, frequency-magnitude relations, and discuss possible climate change impacts on initiation frequency.
Active-layer detachment failures triggered weeks to months after forest fire in central Mackenzie Valley (65°N, discontinuous permafrost zone) are compared to others generated almost immediately by summer meteorological conditions on the Fosheim

Permafrost in Skandinavien. Untersuchungsergebnisse aus Lappland, Jotunheimen und Dovre/Rondane. (Permafrost en Scandinavie. Résultats des recherches effectuées en Laponie et dans les massifs de Jotunheim et de Dovre (Rondane))

Permafrost in Skandinavien. Untersuchungsergebnisse aus Lappland, Jotunheimen und Dovre/Rondane. (Permafrost en Scandinavie. Résultats des recherches effectuées en Laponie et dans les massifs de Jotunheim et de Dovre (Rondane))
Europe ; Géographie de l'Europe ; Haute montagne ; Laponie ; Montagne ; Permafrost ; Périglaciaire ; Scandinavie ; Température du sol ; Zone froide
soundings and studies of snow depth and snow temperature (BTS-values). The lower limit of the continuous permafrost belt corresponds with the -6o C isotherm of the mean annual air temperature, and the discontinuous belt is limited by the -1,5o C isotherm.
In the vicinity of the highest elevations of northern Europe, extensive permafrost occurences could be proved. Two test areas have been investigated in detail by means of ground temperature measurements, hammer seismic soundings, dc-geoelectric

Climatic relationships of permafrost zones in areas of low winter snow-cover

Climatic relationships of permafrost zones in areas of low winter snow-cover
Géographie physique ; Indice climatique ; Permafrost ; Périglaciaire ; Zone froide
In areas with under 50cm snow cover in winter, the permafrost zones are defined by the freezing indices and thawing indices. The warmer boundary of the zone of continuous permafrost traverses the mean annual air temperature (MAAT). The boundary
between discontinuous and sporadic permafrost lies just on the cold side of 0C MAAT. The sporadic permafrost zone includes the zone of ice caves and the regions with patches of ice beneath ponds and peatbogs, out to 5C MAAT at a thawing index of 4000

A discussion on pingos in Mellemfjord, Disko, Central West Greenland

Cold area ; Fjord ; Geomorphogenesis ; Greenland ; Groundwater ; Periglacial features ; Permafrost ; Pingo
Open system, or more correctly, hydraulic pingos, are genetically poorly understood. A continuing problem concerns their need for a perennial groundwater supply (intra- or sub-permafrost). This has to be maintained despite the existence
of continuous permafrost in many areas where they are located. Recent work on Disko Iland has suggested a new type of hydraulic pingo developing only in a marsh environment. It is argued that the marsh setting is not relevant to the formation of these features

Thermal state of permafrost in Russia

Thermal state of permafrost in Russia
Climatic warming ; Cold area ; Global change ; Periglacial features ; Permafrost ; Polar region ; Russia ; Soil temperature ; Thawing ; Thermal regime
to thaw at some limited locations in the continuous permafrost zone. As a result, a northward displacement of the boundary between continuous and discontinuous permafrost zones was observed.
The results of the International Permafrost Association's International Polar Year Thermal State of Permafrost (TSP) project are presented based on field measurements from Russia during the IPY years (2007-09) and collected historical data. Most
ground temperatures measured in existing and new boreholes show a substantial warming during the last 20 to 30 years. Thawing of permafrost is most noticeable within the discontinuous permafrost domain. However, permafrost in Russia is also starting

Slope sediment yield in arid lowland continuous permafrost environments, Canadian Arctic Archipelago

Slope sediment yield in arid lowland continuous permafrost environments, Canadian Arctic Archipelago
Arctic Region ; Canada ; Cold area ; Ellesmere ; Erosion rate ; Model ; Northwest Territories ; Periglacial features ; Permafrost ; Plant cover ; Rill wash ; Sediment budget ; Slope ; Slope gradient ; Soil erosion ; Suspended load
The aims of this paper are : to describe rates of slopewash erosion from a group of runoff plots on the Fosheim Peninsula, Ellesmere Island; to synthesize the limited literature for slopewash in continuous permafrost areas by developing

Hydrological and hydrochemical studies in the permafrost drainage basin of Oobloyah valley, N-Ellesmere island, NWT, Canada in Polar research.

Hydrological and hydrochemical studies in the permafrost drainage basin of Oobloyah valley, N-Ellesmere island, NWT, Canada in Polar research.
; Permafrost ; Périglaciaire ; Zone froide
During the Heidelberg-Ellesmere-island-expedition in 1978 the summerly water balance of this high arctic catchment area with continuous permafrost was investigated. (D'après l'Ed.).

Thermal-contraction-crack networks as evidence for Late-Pleistocene permafrost in Inner Mongolia, China

Thermal-contraction-crack networks as evidence for Late-Pleistocene permafrost in Inner Mongolia, China
China ; Cryoturbation ; Ice wedge ; Inner Mongolia ; Palaeo-environment ; Palaeoclimate ; Periglacial features ; Permafrost ; Pleistocene
of polygonal networks. The presence of these periglacial phenomena show that the southern limit of continuous permafrost in Inner Mongolia occurred south of 38°N during the Last Glacial Maximum.

Twenty years of data on climate-permafrost-active layer variations at the lower limit of alpine permafrost, Marmot Basin, Jasper National Park, Canada

Twenty years of data on climate-permafrost-active layer variations at the lower limit of alpine permafrost, Marmot Basin, Jasper National Park, Canada
Active layer ; Air temperature ; Alberta ; Canada ; Geothermics ; Groundwater ; Heat transfer ; Mountain ; Periglacial features ; Permafrost ; Snow cover ; Soil temperature
to the lower limit of continuous permafrost. The 20-year record permits the identification of 2 new processes in heat transfer in the ground which have not previously been demonstrated in the natural environment.

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