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  • Relict sorted patterned ground in Lesotho
  • Cryoturbation ; Freezing ; Lesotho ; Palaeo-environment ; Patterned ground ; Periglacial features ; Permafrost ; Pleistocene
  • Relict sorted patterned ground is described from an upland interfluve on the Lesotho-South Africa border at an elevation of 3280 m a.s.l. The site comprises 2-4° slope angles. Frost penetration through the regolith is inferred to have been to 1 m
  • depth during pattern formation. Sorting is thought to have resulted from deep seasonal freezing during the depressed temperatures of the Late-Pleistocene Last Glacial Maximum. No direct evidence for permafrost is documented.
  • 2004
  • Generalized linear modelling in periglacial studies : terrain parameters and patterned ground
  • Cold area ; Finland ; Geographical information system ; Model ; Patterned ground ; Periglacial features ; Regression analysis ; Soil moisture ; Topography
  • Generalized linear models (GLM) are mathematical extensions of linear models. This paper demonstrates GLM model-building procedures step-by-step for the distribution and abundance of active patterned ground in northern Finland. Both the distribution
  • and abundance models clearly indicate an increasing activity of patterned ground with increasing soil moisture and proportion of concave topography. Activity decreases with increasing altitude. The AA. conclude that GLM techniques combined with a geographic
  • 2004
  • Further examples of ventifacts and unusual patterned ground from the Falkland Islands, South Atlantic
  • Aeolian features ; Aeolian transport ; Clay ; Cold area ; Falkland Islands ; Island ; Patterned ground ; Peat ; Sediment filling ; South Atlantic Ocean
  • Examples of ventifacts and forms of unusual patterned ground that differ in situation, characteristics and/or origin to types reported previously are described from the Falkland Islands : stone polygons on clay loam regolith, stone polygons on peat
  • 2004
  • Using an existing hydrogeologic computer model, the AA. implemented a simple hierarchical approach to modeling surface- and ground-water hydrology in a complex geomorphic setting. The AA. parameterized the model to simulate ground- and surface-water
  • flow patterns through a hierarchical, three-dimensional, quantitative representation of an anabranched montane alluvial flood plain (the Nyack Flood Plain, Middle Fork Flathead River, Montana, USA). This modeling approach appears well suited
  • to heuristic investigations of interactions between flood-plain geomorphology, discharge regime, and resulting patterns of surface and subsurface water routing.
  • 2004
  • Active layer ; Alaska ; Arctic Region ; Climate ; Cold area ; Cryoturbation ; Ecosystem ; Patterned ground ; Soil properties ; Vegetation
  • This paper presents observations of frost boils in northern Alaska. It presents a hypothesis of how vegetation affects small-scale patterned-ground features across the complete Arctic climate gradient. Although not directly part of the Circumpolar
  • 2004
  • Patterns of sediment slug translation and dispersion following typhoon-induced disturbance, Oyabu Creek, Kyushu, Japan
  • Carrying capacity ; Ground survey ; Japan ; Kyushu ; Longitudinal section ; River bed ; Roughness ; Sediment load ; Stream ; Stream flow ; Tropical cyclone ; Years 1990-99
  • and pattern of sediment slugs following disturbance are related to flow conditions, sediment avaibility, and channel bed roughness.
  • 2004
  • Arid area ; Calcrete ; Climatic variation ; Fluvial processes ; Groundwater ; Jordan ; Micromorphology ; Phreatic ground water ; Quaternary ; Sedimentology ; Spatial distribution ; Stream
  • operating in the present-day wadi system. The products of calcretization have been observed to see if the cement patterns and types are uniform or if variations exist spatially and temporally. Calcrete formation has been occurring over significant periods
  • 2004
  • Australia ; Micromorphology ; Patterned ground ; Regolith ; Silicrete ; Taffoni ; Water erosion ; Weathering
  • 2004
  • Fluvioglacial features ; Freezing ; Patterned ground ; Pebbles ; Periglacial features ; Permafrost ; Pleistocene ; Poland ; Sedimentary structure ; Sedimentology ; Vertical movement
  • 2004
  • Air temperature ; Freezing ; Gelifluction ; Lesotho ; Mountain ; Patterned ground ; Periglacial features ; Snow ; Snow cover ; Soil temperature ; Thermal regime
  • 2004
  • Ground thermal profiles from Mount Kenya, East Africa
  • Ground freezing ; Kenya ; Kenya Mount ; Mountain ; Snow cover ; Soil temperature ; Temperature ; Thermal regime ; Tropical zone
  • This paper presents and compares ground thermal regimes at 4200 and 4800 m a.s.l. on Mount Kenya's southern flank. The aim is to provide an understanding of near-surface cryo-thermal dynamics in this equatorially driven climate. The AA. demonstrate
  • that a greater longevity of contemporary thin snow cover at 4800 m a.s.l. permits progressive sub-surface cooling with depth. However, the near-surface ground temperature profiles suggest that conditions are not conducive to permafrost development at these sites.
  • 2004
  • Application of satellite remote sensing techniques to frozen ground studies
  • Active layer ; Alaska ; Freeze-thaw cycle ; Frozen ground ; Permafrost ; Remote sensing ; Sar imagery ; Satellite ; United States of America
  • 2004
  • Hydrological connectivity of soil pipes determined by ground-penetrating radar tracer detection
  • Soil pipes are common and important features of many catchments, particularly in semi-arid and humid areas, and can contribute a large proportion of runoff to river systems. Ground Penetrating Radar (GPR) has been used for non-destructive
  • 2004
  • Meteorological control on interannual spatial and temporal variations in snow cover and ground thawing in two northeast greenlandic Circumpolar-Active-Layer-Monitoring (CALM) sites
  • Data on snow cover depletion and ground thawing at 2 sites at Zackenberg, in high arctic northeast Greenland, are presented from 1996 to 2002, and their meteorological control discussed.
  • 2004
  • Explanations of the spring peak in ground-level ozone in the Southwestern United States
  • Many remote locations in the Northern Hemisphere have a spring peak, rather than a summer peak, in ground-level ozone concentrations, and the principal cause is presumed to be stratosphere-troposhere exchange (i.e., stratospheric intrusions). Grand
  • Canyon National Park (GCNP) in northern Arizona also has a spring peak, and the purpose of this study is to explore the impact of stratospheric intrusions and another process synoptic-scale pollutant transport on ground-level ozone levels at GCNP from
  • 2004
  • Monitoring frozen ground (2004-2005) at Madoi in the source area of the Yellow River, China
  • This paper reports the first year's results of monitoring of environmental factors at Madoi, northeastern Tibetan Plateau : air and ground temperatures, precipitation, snow depth, soil moisture and groundwater level. The data show either the absence
  • 2004
  • cracking and pingo growth. Annual freeze-thaw action dominates the ground, resulting in extensive occurence of solifluction and shallow landslides on soil slopes. Special attention will be paid to how permafrost and the overlying active layer constrain
  • the morphology and movement of the ground. Finally, a brief prediction will be given on environmental changes in response to ongoing global warming.
  • 2004
  • Geophysics ; Glacier ; Ground survey ; Little ice age ; Mountain ; Periglacial features ; Permafrost ; Pyrénées ; Spain ; Stratigraphy
  • bodies (debris rock glaciers and moraine deposits) located in this proglacial environment. Ground ice was propected using 2 DC (direct current) resistivity techniques. Results from the Posets and La Paul glaciers forefields are presented here
  • 2004
  • Antarctica ; Cold area ; Creep ; Freezing ; Ground freezing ; Periglacial features ; Slope ; Slope dynamics
  • 2004
  • Active layer ; Arctic Region ; Canada ; Cold area ; Ground survey ; Microclimate ; Northwest Territories ; Permafrost ; Soil properties ; Soil temperature ; Thawing ; Vegetation
  • 2004