inscription
PORTAIL D'INFORMATION GÉOGRAPHIQUE

Résultats de la recherche (2160 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
The acquisition of ground data for surveys based on remotely sensed data in Remote sensing application in agriculture and hydrology.
  • The acquisition of ground data for surveys based on remotely sensed data in Remote sensing application in agriculture and hydrology.
Evaluation of natural surfaces in a dry tropical environment by remote sensing and ground survey
  • Evaluation of natural surfaces in a dry tropical environment by remote sensing and ground survey
  • Ground survey ; Inventory ; Land use ; Mauritania ; Pastoral ; Remote sensing ; Sahel ; Sampling ; Satellite imagery ; Vegetation
Ground beetles on Mt. Usu six years after the 1977-78 eruptions
  • Ground beetles on Mt. Usu six years after the 1977-78 eruptions
  • Survey made of the ground beetles on and around Mt. Usu which had suffered vegetational damage from volcanic eruptions in 1977-78. A total of 2485 specimens of 29 species were collected.
Frozen ground monitoring (2004-2006) in the source area of the Yellow River, China
  • Frozen ground monitoring (2004-2006) in the source area of the Yellow River, China
  • China ; Climatic warming ; Ground freezing ; Ground survey ; Mountain ; Periglacial features ; Permafrost ; Seasonal variation ; Soil temperature ; Temperature ; Tibet
  • Ground thermal and hydrological regimes at Madoi (4273m ASL), northeastern Tibetan Plateau, are described on the basis of 2 years of automatic and manual observations of air and ground temperatures, precipitation, snow depth, soil moisture
  • and groundwater level. Extrapolation of the mean annual ground temperatures suggests that permafrost is unlikely present below an unfrozen talik, while it possibly disappeared within the last few decades. Soil moisture and groundwater level primary vary
Assessing the ability of airborne LiDAR to map river bathymetry
  • Airborne bathymetric LiDAR was collected for 220 river kilometers in the Yakima and Trinity River Basins in the USA. Concomitant with the aerial data collection, ground surveys of the river bed were performed in both basins. The AA. assess
  • to ground surveys for magnitude and spatial variation.
  • the quality of the bathymetric LiDAR survey from the perspective of its application toward creating accurate, precise and complete streambed topography for numerical modelling and geomorphological assessment. Measurement error is evaluated with respect
Mapping the spatial distribution of geomorphological processes in the Okstindan area of northern Norway, using Geomorphic Process Units as derived from remote sensing and ground survey
  • Mapping the spatial distribution of geomorphological processes in the Okstindan area of northern Norway, using Geomorphic Process Units as derived from remote sensing and ground survey
  • and these were derived from the combination of Landsat satellite imagery (TM and ETM+) with stereo aerial photographs (used to construct a Digital Elevation Model) and ground survey. The Okstindan study area is sub-arctic and mountainous and is dominated
Ground penetrating radar survey and stratigraphic interpretation of the Plan du Lac rock glaciers, Vanoise Massif, Northern French Alps
  • Ground penetrating radar survey and stratigraphic interpretation of the Plan du Lac rock glaciers, Vanoise Massif, Northern French Alps
Ground radiometry and airborne multispectral survey of bare soils in The Natural Environment Research Council's Airborne Thematic Mapper campaigns 1983 and 1984.
  • Ground radiometry and airborne multispectral survey of bare soils in The Natural Environment Research Council's Airborne Thematic Mapper campaigns 1983 and 1984.
Ground penetrating Radar applied to the study of peat bogs and moors
  • Ground penetrating Radar applied to the study of peat bogs and moors
  • Ground Penetrating Radar (GPR) is a shallow geophysical exploration technique based on the reflection of electromagnetic impulses. It gives a continuous image of the subsurface, like reflection seismics. The strong attenuation of radar waves in most
  • soils is a major limitation. Peat however has very favourable electrical characteristics resulting in low attenuation and excellent results are obtained from GPR surveys. Several examples Southern Belgium are discussed showing the wide range of possible
Seasonal changes in ground-penetrating radar signature observed at a polythermal glacier, Bylot Island, Canada
  • Seasonal changes in ground-penetrating radar signature observed at a polythermal glacier, Bylot Island, Canada
  • This paper presents the results of 3 ground-penetrating radar (GPR) surveys conducted, in 2002, over the course of a summer ablation season at a polythermal glacier, Stagnation Glacier, Bylot Island, in the Canadian Arctic. The AA. compare
Intensive cooling through an open-work blocky layer : ground temperature monitoring in the Swiss Alps
  • Intensive cooling through an open-work blocky layer : ground temperature monitoring in the Swiss Alps
  • Alps (The) ; Ground survey ; Mountain ; Periglacial features ; Permafrost ; Rock glacier ; Slope gradient ; Snow cover ; Soil temperature ; Switzerland
  • This paper presents the results of two-year monitoring of ground temperatures on two kinds of alpine ground surfaces, a rock glacier and a soil slope in the Upper Engadin, Swiss Alps. The monitoring sites lie close to the regional lower limit
Photogrammetrie auf Expeditionen
  • Ground surveys ; Photogrammetry ; Photointerpretation ; Thematic mapping
Relazioni della campagna glaciologica 1986
  • Alps (The) ; Climate ; Climatic variation ; Glacier ; Glaciology ; Ground survey ; Italy ; Landscape ; Mountain
The rock glaciers on Prins Karls Forland : corrections of surface displacement rates
  • Arctic Region ; Cold area ; Comparative study ; Creep ; Geodesy ; Global Positioning System ; Ground survey ; Permafrost ; Rock glacier ; Svalbard
  • The results from new global positioning system (GPS) surveys in 1998 and 2000 show, that errors exist in the results from terrestrial surveys in 1996. The published displacement values of Berthling et al. (1998) are too large. This note corrects
Morphological analysis of the Sudd region using land survey and remote sensing data
  • Morphological analysis of the Sudd region using land survey and remote sensing data
  • of ground slopes and morphological features on spill and flooding of the seasonally flooded grasslands. Through bathymetric surveys and analysis of Landsat images, depth profiles and cross-sectional depth and flow distributions were established. Data from
  • An analysis of the vast wetland of the Sudd swamps in southern Sudan was designed to assess and describe interdependencies between morphology and hydrology. Findings based on field survey and remote sensing data include an assessment of the effect
  • remote sensing, field survey and historical sources were correlated and correction factors established; the SRTM was found to be partly unsuitable for further assessments. Further analysis of remote sensing data was used to investigate the Sudd's inland
Interannual changes in seasonal ground freezing and near-surface heat flow beneath bottom-fast ice in the near-shore zone, Mackenzie Delta, NWT, Canada
  • Interannual changes in seasonal ground freezing and near-surface heat flow beneath bottom-fast ice in the near-shore zone, Mackenzie Delta, NWT, Canada
  • Canada ; Delta ; Ground freezing ; Ground ice ; Heat flow ; Interannual variability ; Nearshore zone ; Northwest Territories ; Periglacial features ; Permafrost ; Seasonal variability ; Surface temperature ; Water
  • Interannual changes in seasonal ground freezing and near-surface heat flow beneath zones of bottom-fast ice (BFI) were examined over the winters of 2005–06 and 2006–07 within the near-shore zone of the Mackenzie Delta. Winter variability in ground
  • thermal conditions was determined at 3 monitoring sites. When comparing conditions over the two winters, 2005–06 was characterised by a decrease in ice thickness that limited the extent of BFI and seasonal cooling of the ground. These changes in ice
  • [b3] Geological Survey of Canada (Atlantic), Natural resources, Dartmouth, Canada
Trends in the long-term variability of groundwater discharge
  • Annual variation ; Climate ; Discharge ; Flow regime ; Ground survey ; Ground water ; Human impact ; Seasonal variation ; Stream ; USSR ; Water ; Water quality ; Water resources
The significance of global snow and ice cover for global change studies
  • Climatic warming ; Cryosphere ; Floating ice ; Forecast;Prediction ; Glacial features ; Greenhouse effect ; Ground ice ; Ground survey ; Ice ; Permafrost ; Remote sensing ; Sea ice ; Snow ; Spatial analysis
Long-term rates of mass wasting in Mesters Vig, northeast Greenland : notes on a Re-survey
  • Long-term rates of mass wasting in Mesters Vig, northeast Greenland : notes on a Re-survey
  • Climatic warming ; Cold area ; Gelifluction ; Global change ; Greenland ; Ground survey ; Mass movement ; Slope ; Slope gradient
  • Re-surveys of surviving mass-wasting target lines established by A.L. Washburn in the late 1950s in the Mester Vig area, northeast Greenland, are used to derive estimates of long-term mass wasting in the area. These long-term rates suggest a general
Geophysical surveys designed to delineate the altitudinal limit of mountain permafrost : an example from Jotunheimen, Norway
  • Geophysical surveys designed to delineate the altitudinal limit of mountain permafrost : an example from Jotunheimen, Norway
  • Cold area ; Geophysics ; Ground survey ; Mountain ; Norway ; Periglacial features ; Permafrost ; Snow cover ; Spatial distribution ; Temperature
  • permafrost. The good agreement with temperature-based methods validates empirical approaches such as the relation between bottom temperature of snow cover (BTS) and permafrost occurences, and further supports the findings from the geophysical surveys.