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Numerical simulation of the impacts of climate warming on a permafrost mound
  • Numerical simulation of the impacts of climate warming on a permafrost mound
  • Canada ; Climatic warming ; Cold area ; Numerical model ; Periglacial features ; Permafrost ; Quebec ; Simulation ; Thawing
  • Canada ; Dégel ; Modèle numérique ; Pergélisol ; Périglaciaire ; Québec ; Réchauffement climatique ; Simulation ; Zone froide
  • permafrost nearer to the surface and accelerates its thawing. It should be included in any numerical simulation.
  • to the cryostratigraphy of the mound, the unfrozen water content, thermal conductivity and volumetric heat capacity of the marine sediments comprising the mound were integrated in the simulation. Thaw settlement, the direct results of ice melting in permafrost, brings
Numerical simulation of the inception of channel meandering
  • Numerical simulation of the inception of channel meandering
  • Bank erosion ; Channel geometry ; Meander ; Numerical model ; Sediment load ; Sediment transport ; Simulation ; Stream ; Suspended load
  • Charge en suspension ; Charge solide ; Cours d'eau ; Erosion des berges ; Géométrie hydraulique ; Modèle numérique ; Méandre ; Simulation ; Transport sédimentaire
  • The inception of channel meandering is the result of the complex interaction between flow, bed sediment, and bank material. This study presents a two-dimensional numerical model that links a physically based bank erosion model with the bend
  • migration model to simulate the formation process of meandering channels. The model replicates the downstream translation and lateral extension of meandering loops reasonably well.
Numerical simulations of salinity, turbidity and sediment accumulation in the Scheldt Estuary in Ecohydrodynamics.
  • Numerical simulations of salinity, turbidity and sediment accumulation in the Scheldt Estuary in Ecohydrodynamics.
  • Belgique ; Ecologie ; Ecosystème ; Escaut ; Estuaire ; Géographie physique ; Hydrodynamique ; Modèle ; Modèle de dispersion ; Méthodologie ; Salinité ; Simulation ; Sédimentologie ; Turbidité
  • A hydrodynamic and a dispersion model have been devised. Both models are two-dimensional, vertically integrated, and are solved numerically with a multioperational finite difference scheme (grid 300 300 m). (LW).
Numeric simulation of permafrost degradation in the Eastern Tibetan Plateau
  • Numeric simulation of permafrost degradation in the Eastern Tibetan Plateau
Origin of precipitating water in a numerical simulation of the July climate
  • Origin of precipitating water in a numerical simulation of the July climate
  • Circulation atmosphérique ; Climat ; Continentalité ; Cycle de l'eau ; Géographie physique ; Humidité atmosphérique ; Modèle ; Monde ; Précipitation ; Simulation
Geothermal reservoir simulation. 2. Numerical solution techniques for liquid-and vapor-dominated hydrothermal systems
  • Geothermal reservoir simulation. 2. Numerical solution techniques for liquid-and vapor-dominated hydrothermal systems
  • Application des deux modèles et évaluation des techniques de simulation pour l'ingéniérie géothermale.
Possible use of active microwave remote sensing data for prediction of regional evaporation by numerical simulation of soil water movement in the unsaturated zone
  • Possible use of active microwave remote sensing data for prediction of regional evaporation by numerical simulation of soil water movement in the unsaturated zone
  • Analyse numérique ; Eau du sol ; Evaporation physique ; Evapotranspiration ; Géographie physique ; Image radar ; Radiomètre ; Simulation ; Sol ; Technique de recherche ; Télédétection
Numerical modelling of aeolian erosion over rough surfaces
  • Numerical modelling of aeolian erosion over rough surfaces
  • Aeolian features ; Dust ; Numerical model ; Roughness ; Shear stress ; Simulation ; Turbulence ; Wind erosion
  • Contrainte de cisaillement ; Eolien ; Erosion éolienne ; Modèle numérique ; Poussière ; Rugosité ; Simulation ; Turbulence
  • Three-dimensional numerical simulations, simulating wind flow over a bed of particles covered by roughness elements, were conducted in order to investigate the effect of roughness elements on the shear stress near the surface. The results confirm
  • that the erosion of soil by wind is strongly attenuated by the presence of roughness elements on the surface and depends on the geometric properties of the roughness elements. Based on the new numerical results obtained, a refinement of existing theoretical
One-dimensional transitional behaviour in saltation
  • Aeolian features ; Aeolian transport ; Model ; Numerical model ; Sand ; Simulation ; Wind speed
  • Eolien ; Modèle ; Modèle numérique ; Sable ; Simulation ; Transport éolien ; Vitesse du vent
  • One-dimensional simulations of the unsteady saltation process show that the transport rate's response depends on the amplitude and frequency of the wind fluctuations. The numerical model presented in this paper is capable of simulating temporal
  • variations in wind speed. The wind velocity is varied with an unsteady upper boundary condition. The model predicts different transient behaviour for different heights of the simulation, i.e. different wind tunnel heights.
Field and computer simulation experiments on the formation of desert pavement
  • Field and computer simulation experiments on the formation of desert pavement
  • Arizona ; Domaine aride ; Erosion des sols ; Etats-Unis ; Expérimentation ; Modèle ; Pavage désertique ; Simulation de pluie ; Splash
  • Arid area ; Arizona ; Experimentation ; Model ; Rainfall simulation ; Soil erosion ; Splash ; United States of America
  • of these field simulations were then compared with numerical simulations to check the extent to which the simulation model of Wainwright et al. (1994) reproduces the effects of raindrop erosion.
  • A series of rainfall simulation experiments was carried out at the Walnu Gulch Experimental Watershed, Tombstone, Arizona, to observe the speed at which desert pavement surfaces could be re-established following disturbance. The results
Numerical simulation of vertical marsh growth and adjustment to accelerated sea-level rise, North Norfolk, UK
  • Numerical simulation of vertical marsh growth and adjustment to accelerated sea-level rise, North Norfolk, UK
  • Coastal environment ; Coastal marsh ; England ; Eustatism ; Fauna ; Flood ; Flora ; Global change ; Model ; Numerical model ; Sea level ; Sedimentation ; United Kingdom
  • This paper outlines the implementation and application of a refined one-dimensional model designed to simulate the vertical adjustment of marsh surfaces to various combinations of sediment supply, tidal levels and regional subsidence
Micro- and mesoclimatology
  • Bibliographie ; Climat urbain ; Climatologie ; Forêt ; Microclimat ; Modèle ; Simulation
  • Bibliography ; Climatology ; Forest ; Microclimate ; Model ; Simulation ; Urban climate
  • Three themes have been chosen for this report. The first is a methodological one, underlining the continuing importance of numerical simulation techniques in the investigation of small-scale climatic phenomena. The two remaining themes explore
Numerical framework for geomorphological experiments
  • Numerical framework for geomorphological experiments
  • Earth surface processes ; Erosion ; Fluvial erosion ; Model ; Numerical model ; Sediment transport ; Slope dynamics ; Vertical movement
  • In this work the AA. present a numerical framework for simulation of surface processes and landforms. The model is called SIGNUM (Simple Integrated Geomorphological NUmerical Model) and is a Matlab, TIN-based landscape evolution model. The AA. use
  • the model to show a few examples of simulated topographic surfaces evolved through application of mathematical expressions for hillslope and fluvial erosion, channel sediment transport and surface uplift. Although work in the field of computer simulation
A numerical approach to interdependent location decisions in The Los Angeles Meeting, Novembre 1979.
  • A numerical approach to interdependent location decisions in The Los Angeles Meeting, Novembre 1979.
  • ; Simulation ; Stratégie d'entreprise ; Utilisation du sol
Settlement formation. Part II : numerical simulation
  • Settlement formation. Part II : numerical simulation
  • Calcul économique ; Choix spatial ; Densité de population ; Espace-temps ; Généralités sur la géographie ; Migration ; Modèle dynamique ; Peuplement ; Probabilité ; Simulation
  • Simulations effectuées à partir de la théorie dynamique du peuplement : choix explicite de la probabilité d'association spatiale des fonctions de production et de consommation, calibration des paramètres. Les structures du peuplement résultent de
Simulating meander evolution of the Geul River (the Netherlands) using a topographic steering model
  • Simulating meander evolution of the Geul River (the Netherlands) using a topographic steering model
  • Channel geometry ; Meander ; Netherlands (The) ; Numerical model ; Sediment budget ; Simulation ; Stream ; Watershed
  • Bassin-versant ; Bilan sédimentaire ; Cours d'eau ; Géométrie hydraulique ; Modèle numérique ; Méandre ; Pays-Bas ; Simulation
  • The AA. examine the meandering character of the Geul River using a numerical river meandering model. The main aim is to test and calibrate a topographic steering meander model. In this case study, special attention is paid to the incorporation
Numerical analysis of groundwater level fluctuations through linear excavations. A case of Joban motorway at northwestern part of Shimousa plateau
  • Numerical analysis of groundwater level fluctuations through linear excavations. A case of Joban motorway at northwestern part of Shimousa plateau
  • Eau souterraine ; Géographie de l'Asie ; Honshu ; Japon ; Kanto ; Niveau piézométrique ; Simulation
  • Des modèles de simulation permettent de comprendre l'impact de constructions linéaires de type autoroute sur le niveau des eaux souterraines. - (SGA)
Equilibration of saltation
  • Eolien ; Modèle ; Simulation ; Sédimentologie ; Transport éolien ; Turbulence ; Vent
  • Aeolian features ; Aeolian transport ; Model ; Sedimentology ; Simulation ; Turbulence ; Wind
  • This report presents a two-dimensional numerical model of the grain-wind interactive process, which was developed out of the existing one-dimensional model by McEwan (McEwan and Willetts, 1993). The computer program was rewritten to simulate
  • behaviour of the flow and the grain cloud in 2 spatial dimensions (downwind and height) and time. The effects of turbulence were simulated via random fluctuations in the entrainment of particles.
Simulation of slope development and the magnitude and frequency of overland flow erosion in an abandoned hydraulic gold mine in Models in geomorphology.
  • Simulation of slope development and the magnitude and frequency of overland flow erosion in an abandoned hydraulic gold mine in Models in geomorphology.
  • Géographie physique ; Géomorphodynamique ; Modèle numérique ; Simulation ; Versant
  • Construction and use of a numerical simulation model of hillslope development to assess the contribution of various runoff magnitudes to soil erosion and the long-term development of hillslopes in northern California.
Numerical investigation into the influence of geometry and construction materials on urban street climate
  • Numerical investigation into the influence of geometry and construction materials on urban street climate
  • Applied climatology ; Energy balance ; Microclimate ; Model ; Numerical model ; Temperature ; Urban climate ; Urban construction
  • A numerical model is developed for simulating the nocturnal cooling of the ground and walls in typical urban canyons. The model is capable of dealing with homogeneous as well as inhomogeneous (layered) soil and wall substrates. Experiments carried