inscription
PORTAIL D'INFORMATION GÉOGRAPHIQUE

Résultats de la recherche (4459 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • The heat flow field in mainland UK
  • Belts of relatively high flux correspond to zones of crust enriched in radioactive heat production to 15km depth. The enrichments were introduced into the crust by granitic magmas.
  • New Terrestrial heat flow measurements on the Nazca plate
  • The relation between heat flow, sediment thickness and age in the Eastern Pacific
  • Within-slope variability of ground heat flux, subarctic Yukon
  • Canada ; Cold area ; Heat flow ; Permafrost ; Slope gradient ; Soil moisture ; Soil properties ; Soil temperature ; Spatial variation ; Subarctic zone ; Thawing ; Watershed ; Yukon
  • This study examined local variability of heat flux within a north-facing hillslope in Wolf Creek basin, Yukon, during the thawed season of 1997. Ground heat flux was calculated by : 1) assessing vertical conduction and convection inputs using
  • nearsurface temperature gradients and rainfall and 2) combining the sensible heat from ground temperature change with the latent heat associated with melting ground ice. Discussion of the effectiveness of these 2 approaches in determining ground heat flux
  • Using the solutions of equation of heat moisture transfer under conditions of relative humidity assignment on acting surface and convergence of heat balance the paper gives the calculated formulas for determination of change of turbulent heat flow
  • under irrigation and heat expenditures on evaporation. The analysis showed that maximum influence of irrigation on evaporation and turbulent flow of heat is revealed in most arid regions - in eastern part of Central Karakum and western part of Kyzylkum
  • . Here, in July, supplementary evaporation by irrigation reaches 250 mm, but the changes of turbulent heat flow - 100-110 Vt/m2 and even more.
  • Comparisons between zonal and meridional eddy sensible heat transport in the northern hemisphere winter
  • Asian part of Russia ; Atmospheric circulation ; Heat flow ; North America ; Siberia ; Temperature ; Troposphere ; Winter
  • The size and geographical distribution of the zonal eddy sensible heat flux and its divergence in the Northern Hemisphere winter are examined. Special attention is paid to the zonal eddy contribution to the total heat transport and the relationship
  • between the zonal and meridional heat transport. The heat fluxes are calculated using 700mb air temperatures and geostrophic winds spanning the period 1947-1987. Changes in atmospheric circulation strengths may be interpreted in terms of energy flux
  • The most important energy source of the Earth is thermal energy released by radioactive disintegration of matter. Regional differences in the geothermal gradient and heat flow are studied. The role of radioactive heat in plate tectonics is tackled
  • Albedo ; Heat flow ; Kenya ; Microclimate ; Radiation ; Tea ; Vegetation
  • heat flux and the sensible heat fluxes between the canopy and the air and that into and out of the soil. The largest proportion of net radiation was consumed by the latent heat flux. Advection was found to be minimal.
  • Spatial analysis of the factors contributing to the relationship between the transient, meridional eddy sensible, and latent heat flux in the southern hemisphere
  • Atmospheric dynamics ; Atmospheric moisture ; Climate ; Climatic variability ; Forecast ; Heat flow ; Principal components analysis ; Southern hemisphere ; Spatial analysis ; Spatial statistics ; Temperature ; World
  • In this paper principal component analysis (PCA) and singular value decomposition (SVD) are used to define the importance of the variables contributing to the relationship between the transient latent and sensible heat fluxes and to show
  • their temporal and spatial variation. Both methods of analysis produced 2 very important uncorrelated modes of variability in January and July, indicating that the transient heat fluxes are influenced by few controlling factors. The AA. suggest that these modes
  • of variability represent the influences of the meridional temperature gradient, atmospheric moisture, and activity within the source and sink regions of the transient heat fluxes.
  • The August 2007 heat wave in North Carolina : meteorological factors and local variability
  • Air mass ; Atmospheric circulation ; Drought ; Heat flow ; Heat wave ; North Carolina ; Soil moisture ; Spatial variation ; United States of America ; Weather type
  • A critical aspect of the August 2007 heat wave was the observed variability in heat and humidity across the different geographic regions of North Carolina. The highest maximum temperatures occurred most frequently in the Piedmont and Sandhills
  • regions, while minimum temperatures were exceptionally high along the coast. The broad-scale pattern of heat can be tied to adiabatic warming associated with subsidence downstream of a persistent upper-level ridge centered over the Mississippi River Valley
  • . Regional to local variations in the heat and humidity across North Carolina are linked to upwind sensible heat fluxes associated with major soil moisture deficits, adiabatic warming connected with downsloping winds off the Appalachian Mountains
  • , and the depth of the mixing layer. Along the coast, the pattern of heat and humidity was tied to the positioning of a mesoscale thermal trough and the presence and strength of the sea-breeze circulation.
  • Geothermal control on flow patterns in the last glacial maximum ice sheet of Iceland
  • Antarctica ; Cold area ; Geothermal energy ; Heat flow ; Iceland ; Meltwater ; Remote sensing ; Rift ; SPOT ; Tectonics ; Volcanism
  • In Iceland, tectonics and volcanism, due to lithospheric spreading at the Mid-Atlantic Ridge, occurred during the last glaciation beneath an ice sheet approximately 1000 m thick. From a reconstruction of the flow patterns of this ice sheet, and from
  • simple calculations, the AA. illustrate how ice dynamics can be controlled by the geothermal heat flux associated with tectonic and volcanic activity.
  • Urban surface heat fluxes infrared remote sensing inversion and their relationship with land use types
  • ASTER ; Heat flow ; Heat island ; Honshu ; Japan ; Land use ; Model ; Plant cover ; Remote sensing ; Temperature ; Town ; Urban climate
  • Using ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) infrared remote sensing data the AA. inversed the parameters of urban surface heat fluxes applying the PCACA model and theoretical position algorithm
  • , and then they analyzed the influence of different land use types on the surface heat fluxes and energy balance. In this study, Kumagaya, a city in Saitama Prefecture, Japan, was selected as the experimental area. The result shows that the PCACA model is feasible
  • for the surface heat fluxes estimation in urban areas because this model requires less parameters in the procedure of heat fluxes estimation in urban areas with complicated surface structure and can decrease the uncertainty. And they found that different land-use
  • types have indicated the height heterogeneity on the surface heat fluxes significantly.
  • Bathymetry ; Canada ; Evaporation ; Heat balance ; Heat flow ; Lake ; Northwest Territories ; Seasonal variation ; Surface temperature ; Temperature ; Wind speed
  • This paper summarizes the cross-lake variations of meteorology, evaporation, heat fluxes, thermal response, heat content, and physical limnological processes based on 1998 summer and 1998/1999 winter over-lake measurement platforms within the main
  • -lake section of Great Slave Lake. The long-term objectives of this research include modeling the heat and mass exchange components, assessing potential climate change impacts, and quantifying the interannual variabilities. These analyses
  • 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
  • conditions had a greater effect on the thermal conditions at sites where water depths were close to the maximum ice thickness. The short ice contact times at these sites are important to the thermal state of permafrost, as only minimal heat exchange
  • Atmospheric circulation ; Climatic variation ; Evapotranspiration ; Global change ; Heat flow ; Land use ; Plant canopy ; Poland ; Rural area
  • This paper shows that : modification of the plant cover in an agricultural landscape influences the vertical flux of sensible heat; the changes in land-use pattern influence the vertical fluxes of sensible and latent heat at the scale
  • of the Wielkopolska region. The last studied problem concerns the mutual effects of climate and land-use changes on the intensity of sensible and latent heat fluxes in Poland. The effects of global climate change can be mitigated to some extent by manipulation
  • The meridional flux of eddy sensible heat at 700 mb in the Northern Hemisphere winter
  • Annual variation ; Atmosphere ; Atmospheric circulation ; Climatology ; Heat flow ; Teleconnection ; Temperature
  • The long-term geographical distribution of the winter, meridional eddy sensible heat flux is shown and is compared with the flux variation over the winters of 1976-1987. Results indicate that while the winter mean total eddy flux possesses the same
  • Monitoring and simulation of water, heat, and CO2 fluxes in terrestrial ecosystems based on the APEIS-FLUX system
  • Asia ; Carbon dioxide ; China ; Ecosystem ; Environment ; Environmental degradation ; Environmental management ; Heat flow ; Japan ; Remote sensing ; Simulation ; Water
  • ground observations at 5 sites in different ecological systems in China. The AA. are now using the APEIS-FLUX data to develop an integrated model, which can simulate the regional water, heat, and carbon fluxes. Discussion of the results.
  • Wp yw procesu mieszania sie wod podgrzanych na rozk ady temperatury w rzekach swobodnie p ynacych Effect of the process of mixing up heated waters on the temperature distribution in freely flowing rivers
  • Evaluation of the mathematical modelling of the dispersion process based upon thermal studies. The presented models give satisfactory results when the velocities of heated discharge and water in the river are similar. Applicability depends mostly
  • Basin modelling of temperature and heat flow distributions and permafrost evolution, Urengoy and Kuyumbinskaya areas, Siberia
  • Asian part of Russia ; Cold area ; Heat flow ; Model ; Numerical model ; Palaeoclimate ; Periglacial features ; Permafrost ; Siberia ; Temperature
  • that permafrost thickness and temperature and heat flow distributions with depth in the basins calculated with climate variations of the last 50 ka differ significantly from the more accurate values obtained with climate variations during the last 200 ka, 1 Ma
  • Boundary ; Heat flow ; Landscape ; Natural landscape ; Sandur ; Soil temperature