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  • Characterising relict cryogenic macrostructures in mid-latitude areas of the USA with three-dimensional ground-penetrating radar
  • Ice wedge ; Inheritated geomorphological features ; North Dakota ; Palaeo-environment ; Patterned ground ; Periglacial features ; Permafrost ; Quaternary ; Radar ; Remote sensing ; Rhode Island ; United States of America ; Wisconsin ; Wisconsinan
  • with permafrost and periglacial conditions and provide evidence of climate change. In this study, buried relict cryogenic macrostructures were identified with Ground-penetrating Radar(GPR). On some two-dimensional GPR (2DGPR) records, boundaries with the host
  • information than 2D radar records. When supplemented with adequate ground-truth observations, GPR offers considerable potential for imaging, interpreting and mapping near-surface cryogenic macrostructures in former periglacial environments.
  • 2009
  • Patterns in vegetation composition, surface height and thaw depth in polygon mires in the Yakutian Arctic (NE Siberia) : a microtopographical characterisation of the active layer
  • Active layer ; Asian part of Russia ; Cold area ; Ice wedge ; Microrelief ; Patterned ground ; Periglacial features ; Permafrost ; Plant cover ; Sakha ; Spatial variation ; Tundra
  • 2009
  • Digital elevation model ; LANDSAT ; Moraine ; Mountain ; Nivation hollow ; Patterned ground ; Periglacial features ; Remote sensing ; Snow ; Snow cover ; South Africa ; Spatial analysis ; Thematic Mapper
  • The AA. present a case study from the high Drakensberg, comparing the contemporary spatial pattern of longest-lasting cold-season snow patches with the distribution patterns of active and relic cold region landforms. Two 30 m resolution sets of TM
  • 2009
  • Antarctica ; Cold area ; Ice wedge ; Patterned ground ; Periglacial features ; Permafrost ; Polar region
  • 2009
  • settings and floodplain morphology. Qualitative analysis of LiDAR data allowed the identification of former channel patterns, levees, colluvial hillslope and fan deposits. These results were confirmed by field data, topographic surveys and historical maps
  • . The main aim of this study is to critically compare and evaluate information derived from regional LiDAR imagery and ground truth data in order to assess their suitability for geomorphological mapping in these environments. Furthermore, the AA. investigated
  • 2009
  • Antarctica ; Cold area ; Desert ; Ground freezing ; Microclimate ; Polar region ; Radiation ; Radiation balance ; Soil temperature ; Synoptic climatology
  • patterns and is associated with clear skies. The study was conducted in the interior of Marion Island at Katedraalkrans in the polar desert habitat : scoria and black lava deposits almost completely unvegetated. Therefore this site allows for a direct
  • exchange between atmospheric conditions and ground temperatures. Results and discussion.
  • 2009
  • The aim of the study is to develop a new method for the early night-time near-surface air temperature pattern estimation based on the surface temperature data in the urban area of Szeged (S-Hungary). The surface temperature data have been collected
  • by an airplane-based thermal infrared sensor at an altitude of 2000 m above ground level. The study area was covered by hundreds of images with a spatial resolution of about 2 m. The measured values were calibrated with data of in situ surface measurements
  • 2009
  • Near-surface ground-ice distribution, Kendall Island Bird Sanctuary, Western Arctic Coast, Canada
  • Canada ; Cold area ; Delta ; Ground ice ; Northwest Territories ; Organic materials ; Periglacial features ; Permafrost ; Spatial distribution ; Subsidence ; Thermokarst ; Topography
  • The variation in near-surface ground-ice content of the uppermost 1 m of permafrost was examined by drilling 71 sites within the Kendall Island Bird Sanctuary of the outer Mackenzie Delta, Northwest Territories. The primary aims of the research were
  • : 1) to characterise near-surface ground-ice conditions by terrain type; 2) to investigate the geomorphological controls on ground-ice development; and 3) to estimate, for alluvial wetlands, the combined effect of potential subsidence from ground-ice
  • 2009
  • Ground temperatures in permafrost south of treeline, Mackenzie Delta, Northwest Territories
  • Surface conditions and ground temperatures from 50-cm to 20-m depth were measured at 26 forested sites in the Mackenzie Delta, to determine if differences in forest structure and organic cover between 4 common white spruce forest community types
  • were associated with variations in ground temperature. Modelling, results and discussion.
  • 2009
  • Decadal-scale analysis of ground movements in old landslides in western Belgium
  • The aim of this study is to better understand the current activity of the landslides in the Flemish Ardennes. Based on accurate multi-temporal digital terrain models (DTMs), the AA. map first the areas of ground movement, then they analyse
  • their spatial and temporal distribution as well as the magnitude of the vertical and horizontal ground displacements. After field validation of the detected movements, they finally discuss their controlling factors. While most movements were triggered by intense
  • 2009
  • Internal structure of a barrier beach as revealed by ground penetrating radar (GPR) : Chesil beach, UK
  • Here, the AA. present a three-fold model for the evolution of Chesil Beach (Dorset) based on a series of 9 ground penetrating radar (GPR) traverses located at 3 sites along its length at Abbotsbury, Langton Herring and at Ferry Bridge. The case
  • 2009
  • DInSAR measurements of ground deformation by sinkholes, mining subsidence, and landslides, Ebro River, Spain
  • Differential Interferometric Synthetic Aperture Radar (DInSAR) has been applied to detect and measure different types of natural and human-induced ground deformation in a stretch of the Ebro River valley (Spain) excavated in salt-bearing evaporites
  • 2009
  • This study compares the tree and ground cover of 2 localities having different grazing histories in the tree-line ecotone of Western Norway. Data from the sampling of trees, saplings, seedlings and ground cover, tree age determinations, aerial
  • photographs, interviews and literature research are used. The results show differences in the structure of the tree-line ecotone with regard to tree-age, height, circumference and the structure of the understory. Ground cover differs in species composition
  • 2009
  • The election of the Libyan leader, Muammar Gaddafi, as the chair of the African Union in February 2009, reopened the debate on continentalism versus regionalism, and also provided grounds for fresh analyses on the prospect for an African Economic
  • Community. The paper seeks to highlight these new dimensions and to account for their ideological grounding. - (AJC)
  • 2009
  • Rapid degradation of ground ice in a ventilated talus slope
  • Two deep boreholes instrumented with thermistors and located in a talus slope at 2400 m asl above a lake at Flüela Pass in the eastern Swiss Alps allow the analysis of the evolution of ground temperature and permafrost thickness between 2003
  • variability in active layer depth, rapid permafrost degradation and thinning of ground ice is currently occurring. It is attributed to latent heat transfer from the moving air stream, caused by the flux of vapour from the relatively warm lake water table at 20
  • 2009
  • This paper presents the results of winter monitoring of ground surface temperatures in the alpine zone of the Tatra Mountains, at sites found to have, or to lack, permafrost in the course of previous investigations. The results reveal that: (1
  • connected with the local circulation of cold air over the ground surface. - (BJ)
  • 2009
  • Grounding geographies of economic globalisation : globalised spaces in Chile's non-traditional export sector, 1980-2005
  • 2009
  • the response of ground temperatures to changes in surface conditions, especially snow cover; and 3) discuss the ground temperature at Inuvik in the context of permafrost temperatures in the boreal forest of the Mackenzie River valley and Yukon Territory.
  • 2009
  • Ground-penetrating radar surveys on rock glaciers in the Vanoise Massif (Northern French Alps) : methodological issues
  • Alpes du Nord ; France ; Geophysics ; Glacier ; Ground-penetrating radar ; High mountain ; Methodology ; Mountain ; Rock glacier ; Stratigraphy ; Vanoise
  • 2009
  • Determining the number of manual measurements required to improve peat thickness estimations by ground penetrating radar
  • Canada ; Geophysics ; Ground penetrating radar ; Methodology ; Peat bog ; Quebec ; Radar ; Soil properties
  • 2009