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  • Establishing long-term permafrost observatories for active-layer and permafrost investigations in Alaska : 1977-2002
  • Active layer ; Alaska ; Climatic warming ; Global change ; Observation network ; Periglacial features ; Permafrost ; Thawing ; Years 1980-89 ; Years 1990-99
  • A total of 22 permafrost observatories have been established along a north-south transect of Alaska paralleling the Alyeska oil pipeline from Prudhoe Bay to Glenallen, in undisturbed locations. Proximity to meteorological stations with long weather
  • records has allowed reconstruction of past active-layer and permafrost conditions using calibrated site-specific models. The sites have been used to document a recent warming trend in permafrost and active layer and processes that occur in them
  • 2003
  • Ground ice and soluble cations in near-surface permafrost, Inuvik, Northwest Territories, Canada
  • Active layer ; Canada ; Geochemistry ; Grain size distribution ; Ground ice ; Northwest Territories ; Organic materials ; Periglacial features ; Permafrost ; Soil moisture
  • The distribution of segregated ice and soluble ions in near-surface permafrost were investigated in hummocky terrain near Inuvik. The purposes of this paper are : to present the profiles of ice content in near-surface permafrost from the site
  • ; to determine the rates of moisture migration into permafrost at the site; to describe the geochemical characteristics of the active layer and near surface permafrost; and to estimate moisture and cation contributions to the base of the active layer during
  • periods of permafrost degradation.
  • 2003
  • Evaluation of geophysical techniques for application in mountain permafrost studies.
  • Geophysics ; Methodology ; Mountain ; Permafrost ; Radar ; Seismic reflection ; Temperature
  • Les AA. présentent une évaluation des techniques géophysiques appliquées à l'étude du permafrost en montagne : la tomographie, la sismique réflexion, l'induction électro-magnétique, la radiométrie et les mesures de température de la couverture
  • 2003
  • Climatic conditions and sporadic permafrost in the Maiella Massif (Central Apennines, Italy)
  • Appennino ; Climatic data ; Italy ; Microclimate ; Mountain ; Periglacial features ; Permafrost
  • Climatic data were examinated for some ten weather recording stations, in order to verify the presence of favorable conditions for preserving sparadic mountain permafrost in the Maiella Massif (Central Apennines, Italy). Analyzing the situation
  • it is possible to infer that the bottom temperatures of winter snow cover recorded in the Upper Cannella Valley, where sun irradiation is particularly reduced and wind blows very energetically during the cold period, demonstrate that permafrost can exist even
  • 2003
  • Permafrost mapping of Northeast European Russia based on the period of climatic warming 1970-1995
  • Cartography ; Climatic warming ; European part of Russia ; Geographical information system ; Periglacial features ; Permafrost ; Soil temperature
  • The geographic information system (GIS) Permafrost of the Usa River Basin was developed based on data for permafrost distribution and temperatures obtained for the period of recent warming (1970-1995). In this paper, the AA. describe the main stages
  • 2003
  • Multi-method geophysical investigation of a sporadic permafrost occurrence.
  • Alps (The) ; Geophysics ; Graubünden ; Methodology ; Permafrost ; Switzerland
  • Dans la vallée de la Bever (Engadine supérieure, Alpes orientale suisse), les AA. ont combiné plusieurs méthodes pour étudier le permafrost : sondage géo-électrique à une dimension, résistance tomographique à deux dimensions, sismique réflexion
  • , électromagnétisme. De minces lentilles de permafrost ont ainsi été identifiées à une altitude inférieure à celle de la timberline.
  • 2003
  • Mountain permafrost on the north slope of Mt. Ushkovsky, Central Kamchatka, Russia
  • Asian part of Russia ; Climatic geomorphology ; Inherited features ; Kamchatka ; Mountain ; Periglacial features ; Permafrost ; Soil temperature
  • Comblant une information lacunaire concernant le Kamtchatka, les AA. étudient le permafrost de la face nord du mont Ushkovsky (Kamtchatka central) en mesurant la température du sol. Ils s'intéressent à la limite inférieure du permafrost discontinu
  • 2003
  • Dissolved organic carbon fluxes in a discontinuous permafrost subarctic alpine catchment
  • Interactions of permafrost with climatic, hydrologic and ecosystem processes. Special issue
  • Active layer ; Canada ; Carbon ; Hydrology ; Meltwater ; Periglacial features ; Permafrost ; Runoff ; Water balance ; Watershed ; Yukon Territory
  • The sources and fluxes of dissolved organic carbon (DOC) were investigated within a subarctic catchment with discontinuous permafrost (Granger Basin, Yukon) from 23 June 2001 to 22 June 2002. The A. studies the mechanism whereby DOC is flushed
  • to the stream during spring freshet and summer rainfall events, evaluates what roles permafrost and frozen ground play in DOC flushing, and provides a first-order estimate of annual DOC export.
  • 2003
  • Prediction of formation temperatures in permafrost regions from temperature logs in deep wells - field cases
  • Cold area ; Forecast ; Methodology ; Permafrost ; Soil temperature ; Sounding ; Temperature gradient
  • sections below and above the permafrost base) is presented. Temperature logs conducted in 5 wells verify the method.
  • 2003
  • Shrinking thermokarst ponds and groundwater dynamics in discontinuous permafrost near Council, Alaska
  • Interactions of permafrost with climatic, hydrologic and ecosystem processes. Special issue
  • Alaska ; Groundwater ; Hydrodynamics ; Infiltration ; Periglacial features ; Permafrost ; Pond ; Remote sensing ; Thermokarst
  • 2003
  • Mountain permafrost in Japan : distribution, landforms and thermal regimes
  • Climate ; Hokkaido ; Honshu ; Japan ; Mountain ; Palaeosol ; Permafrost ; Spatial distribution ; Volcano
  • L'étendue et la profondeur du permafrost dans les montagnes japonaises sont évaluées par des mesures géophysiques et par l'analyse des températures du sol. Les sommets de deux volcans sont particulièrement étudiés : le Daisetsu et le Fuji.
  • 2003
  • Investigating mountain permafrost distribution by ground temperature measurements in the Tateyama mountains, the northern japanese alps, central Japan.
  • Climatic geomorphology ; Japan ; Mountain ; Periglacial features ; Permafrost ; Snow ; Soil temperature ; Spatial distribution
  • L'A. étudie la température du sol et la couverture neigeuse dans le cirque de Kuranosuke (montagnes de Tateyama, nord des Alpes japonaises). L'A. analyse la distribution spatiale du permafrost et de la neige.
  • 2003
  • Contemporary permafrost and periglaciation in Asian high mountains : an overview.
  • Asia ; High mountain ; Himalaya ; Latitude ; Periglacial features ; Permafrost ; Rock glacier ; Spatial distribution
  • et à la limite inférieure du permafrost en fonction de la latitude.
  • 2003
  • Illinois ; Mass movement ; Moraine ; Palaeo-environment ; Periglacial features ; Permafrost ; Pingo ; Residual landform ; United States of America
  • remnants, presumably due to the degradation of significant ground ice and permafrost. In this study, the DeKalb mounds are presumed to have developed from an intricate set of glacial dead-ice and mass movement processes. This reinterpretation reflects
  • a range of either discontinuous permafrost or negative permafrost within the paleoenvironment.
  • 2003
  • Simulation of freezing-thawing cycles in a permafrost microcosm for assessing microbial methane production under extreme conditions
  • Arctic Region ; Biogenic process ; Cold area ; Freeze-thaw cycle ; Humid environment ; Micro-organism ; Periglacial features ; Permafrost ; Russia ; Simulation ; West Siberia
  • The AA. describe a new technique for the simulation of natural freezing-thawing cycles of the active layer in a permafrost microcosm. The core temperature, moisture and methane concentration and release in different depths of the microcosm can
  • obtained contribute to the understanding of microbial processes and methane fluxes in permafrost environments in the autumn and early winter.
  • 2003
  • Inversion and interpretation of two-dimensional geoelectrical measurements for detecting permafrost in mountainous regions
  • Alps (The) ; Geophysics ; Model ; Moraine ; Mountain ; Permafrost ; Research technique ; Rock glacier ; Seismic method ; Switzerland
  • hazard in the context of thawing-permafrost-induced landslides and rockfalls. The method is applied to various types of permafrost occurences in the European Alps. The influence of topography, measurement geometry and different inversion parameters
  • 2003
  • Evidence for Late-Pleistocene permafrost in the New Jersey Pine Barrens (latitude 39°N), eastern USA
  • Dating ; Ice wedge ; Inherited features ; New Jersey ; Palaeo-environment ; Periglacial features ; Permafrost ; Pleistocene ; Thermokarst ; United States of America
  • Relict sand wedges, up to 2.5 m deep and 0.4 m wide, are present in the Pine Barrens of southern New Jersey. They indicate the previous existence of permafrost. The wedges are composed predominantly of sand that shows evidence of wind transport
  • ) wedges in southern New Jersey and adjacent Delaware also suggest conditions of deep seasonal frost, probably when the most recent permafrost degraded.
  • 2003
  • Impact of the timing and duration of seasonal snow cover on the active layer and permafrost in the Alaskan Arctic
  • Interactions of permafrost with climatic, hydrologic and ecosystem processes. Special issue
  • Active layer ; Alaska ; Arctic Region ; Model ; Periglacial features ; Permafrost ; Simulation ; Snow cover ; Soil temperature ; Thermal regime
  • This study addresses the impact of variations in the timing and duration of seasonal snow cover on the thermal regime of the active layer and permafrost in the Alaskan Arctic through numerical modelling. Meteorological data from 1995 to 1998
  • 2003
  • One-dimensional DC-resistivity depth soundings as a tool in permafrost investigations in high mountain areas of Southern Norway.
  • Electricity ; Geomorphological mapping ; Glacial features ; Moraine ; Norway ; Permafrost ; Plant cover ; Soil ; Soil water ; Water
  • Le passage de l'eau de l'état non gelé à gelé dans les sols et les roches réduit la capacité à conduire l'électricité, ce qui permet d'identifier les sols gelés. Des mesures géophysiques permettent de mesurer l'épaisseur de permafrost. Les AA. ont
  • mené des études dans le sud de la Norvège. Leur objectif est d'étudier la faisabilité de la méthode de cartographie du permafrost et la validité du modèle.
  • 2003
  • Canada ; Climatic variation ; Cold area ; Geophysics ; Ground survey ; Ice ; Palsa ; Periglacial features ; Permafrost ; Quebec ; Radar
  • The AA. describe the introduction of several new techniques to measure and monitor permafrost properties at a site near the east coast of the Hudson Bay, northern Quebec. Cores taken from the permafrost below the active layer of the lithalsa show
  • numerous oblique and fractured ice lenses indicative of extensive deformation of the lithalsa during its evolution. Examples of results of the new techniques applied in this study are provided. These techniques appear as very promising for permafrost
  • 2003