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Analyse de régression ; Centralité ; Centre-périphérie ; Europe ; Modèle ; Modèle de gravité ; Régionalisation ; Structure spatiale
Centrality ; Core-periphery ; Europe ; Gravity model ; Model ; Regionalization ; Regression analysis ; Spatial structure
The paper deals with the spatial structure of Europe, using spatial moving average, potential model and the bidimensional regression analysis based on gravity model. Many theoretical and practical works aim at describing the spatial structures
, such as zones, axes, formations and polycentric models. Based on some examinations, the engravings of the structures are described. The position of the core area of EU countries clearly justifies the banana shape, while the catching up regions take shape
2013

A spatial autoregressive Poisson gravity model

A spatial autoregressive Poisson gravity model
Analyse de régression ; Analyse spatiale ; Autocorrélation spatiale ; Dépendance spatiale ; Modèle ; Modèle de gravité ; Méthode de Monte Carlo ; Origine-destination ; Processus poissonnien ; Statistique
Gravity model ; Model ; Monte Carlo analysis ; Origin-destination ; Poisson process ; Regression analysis ; Spatial analysis ; Spatial autocorrelation ; Spatial dependence ; Statistics
A Poisson gravity model is introduced that incorporates spatial dependence of the explained variable without relying on restrictive distributional assumptions of the underlying data-generating process. The AA. derive a two-stage nonlinear least
-squares estimator that is hetero-scedasticity-robust and controls for the problem of over- or underdispersion that often is present in the empirical analysis of discrete data . In the model specification, the resulting parameter estimates can
be interpreted as the implied total impact effects defined as the sum of direct and indirect spatial feedback effects. The model is illustrated by analyzing patent citation flows data across European regions.
2013

Spatial distribution of trees and landscapes of the past : a mixed spatially correlated multinomial logit model approach for the analysis of the public land survey data

Spatial distribution of trees and landscapes of the past : a mixed spatially correlated multinomial logit model approach for the analysis of the public land survey data
Arbre ; Dynamique de la végétation ; Etats-Unis ; Forêt ; Modèle ; Modèle logit ; Occupation du sol ; Peuplement forestier ; Végétation
Forest ; Forest stand ; Land utilisation ; Logit model ; Model ; Tree ; United States of America ; Vegetation ; Vegetation dynamics
On reconstitue la végétation forestière des Etats-Unis avant le peuplement européen, à une résolution spatiale plus fine que celle qui est disponible sur la base des Public Land Surveys. L'application du modèle proposé est illustrée par les trois
types d'arbres les plus abondants dans les montagnes d'Arbuckle, Oklahoma du centre-sud. Le pouvoir prédictif des modèles est évalué par rapport à une technique de validation.
2013

CryoGRID 1.0 : Permafrost distribution in Norway estimated by a spatial numerical model

CryoGRID 1.0 : Permafrost distribution in Norway estimated by a spatial numerical model
Années 1981-2010 ; Années 2071-2100 ; Changement climatique ; Distribution spatiale ; Modèle ; Modèle numérique ; Norvège ; Pergélisol ; Périglaciaire
Climatic change ; Model ; Norway ; Numerical model ; Periglacial features ; Permafrost ; Spatial distribution
CryoGRID 1.0 provides an equilibrium model of permafrost distribution in Norway at a spatial resolution of 1 km2. The approach was forced with gridded data on daily air temperature and snow cover. Ground thermal properties for different bedrock
types and sediment covers were derived from surveys and geological maps to yield distributions of thermal conductivity, heat capacity and water content. The distribution of blockfields was derived from satellite images. The model results show
. Modelling suggests that permafrost in equilibrium with the 1981–2010 climate presently underlies between 6.1 per cent and 6.4 per cent of the total area of mainland Norway, an area significantly smaller than that modelled for the Little Ice Age climate (14
%). CryoGRID 1.0 was forced using output from a regional climate model for the 2071–2100 period, which suggests that severe permafrost degradation will occur.
2013

New estimates of permafrost evolution during the last 21 kyears in Eurasia using numerical modelling

New estimates of permafrost evolution during the last 21 kyears in Eurasia using numerical modelling
Déglaciation ; Eurasie ; Modèle ; Modèle numérique ; Pergélisol ; Périglaciaire ; Température de l'air
Air temperature ; Deglaciation ; Eurasia ; Model ; Numerical model ; Periglacial features ; Permafrost
The evolution of past permafrost since the Last Glacial Maximum (LGM) is simulated using the Vrije Universiteit Amsterdam Permafrost (VAMPER) model. This method is different from a proxy-based approach which translates reconstructed air temperatures
to estimate past permafrost extent and thickness. First, a sensitivity analysis was performed to assess the behaviour of the model. Then 5 case studies within Eurasia were performed using mean annual ground surface temperatures derived from an Earth system
model as the surface forcing. In Central and West Siberia, the simulated LGM permafrost thicknesses agree well with previous estimates. The LGM and present-day estimates for South Russia are underestimated, which is likely due to a highly simplified land
-atmosphere coupling. In West and Central Europe, however, the VAMPER model was not able to produce permafrost during LGM conditions, which is due to previously recognised biases of the Earth system model.
2013

Modeling policy and agricultural decisions in Afghanistan

Modeling policy and agricultural decisions in Afghanistan
Afghanistan ; Agriculteur ; Agriculture ; Culture licite ; Décision ; Modèle ; Modèle basé-agent ; Pavot ; Prix agricole ; Récolte ; Simulation
Afghanistan ; Agricultural price ; Agriculture ; Crop ; Decision ; Farmer ; Model ; Poppy ; Simulation
This paper presents an agent-based model that simulates policy scenarios to characterize how the production of poppy can be dampened and replaced with licit crops over time. The model is initialized with spatial data, including transportation
2013

A coregionalized model to predict housing prices

A coregionalized model to predict housing prices
Analyse spatiale ; Andalucía ; Coût du logement ; Distribution spatiale ; Dépendance spatiale ; Espagne ; Granada ; Logement ; Marché immobilier ; Modèle co-régionalisé ; Modèle hédoniste
Andalusia ; Granada ; Hedonistic model ; Housing ; Housing cost ; Real estate market ; Spain ; Spatial analysis ; Spatial dependence ; Spatial distribution
Les AA. présentent un modèle de régression hédonique avec des perturbations co-régionalisées et des données hétérotopiques afin de déterminer les prix immobiliers à Grenade en Espagne. Ce modèle a deux équations : la première utilise les données du
2013

The use of dynamic global vegetation models for simulating hydrology and the potential integration of satellite observations

The use of dynamic global vegetation models for simulating hydrology and the potential integration of satellite observations
Bassin-versant ; Biogéographie ; Changement climatique ; Changement global ; Cycle de l'eau ; Dynamique de la végétation ; Ecoulement ; Hydrologie ; Impact ; Incertitude ; Modèle ; Simulation ; Télédétection ; Végétation
Biogeography ; Climatic change ; Global change ; Hydrology ; Impact ; Model ; Remote sensing ; Runoff ; Simulation ; Uncertainty ; Vegetation ; Vegetation dynamics ; Water cycle ; Watershed
Dynamic global vegetation models (DGVMs )are discussed and comparisons of model inputs and formulations are made among and between DGVMs and global hydrological models. It is shown that the configuration of process representations and data inputs
are what makes a given DGVM unique within the family of vegetation models. The variety of available climatic forcing datasets introduces uncertainty into simulations of hydrological variables. It is proposed that satellite-derived data, validated thoroughly
, could be used to improve the quality of model evaluations and augment ground-based observations, particularly where spatial and temporal gaps are present. This would aid the reduction of model uncertainties and thus potentially enhance our understanding
2013

A review on statistical models for identifying climate contributions to crop yields

A review on statistical models for identifying climate contributions to crop yields
Adaptation ; Agroclimatologie ; Analyse spatiale ; Analyse statistique ; Changement climatique ; Espace-temps ; Impact ; Modèle ; Rendement agricole
Adaptation ; Agroclimatology ; Climatic change ; Crop yield ; Impact ; Model ; Space time ; Spatial analysis ; Statistical analysis
This paper introduces 3 main statistical methods, i.e., time-series model, cross-section model and panel model, which have been used to identify such issues in the field of agrometeorology. Generally, research spatial scale could be categorized
into 2 types using statistical models, including site scale and regional scale (e.g. global scale, national scale, provincial scale and county scale). Four issues exist in identifying response sensitivity of crop yields to climate change by statistical
models. The issues include the extent of spatial and temporal scale, non-climatic trend removal, colinearity existing in climate variables and non-consideration of adaptations. Respective resolutions for the above 4 issues have been put forward
in the section of perspective on the future of statistical models.
2013

Evapotranspiration estimation methods in hydrological models

Evapotranspiration estimation methods in hydrological models
Bilan hydrique ; Cycle de l'eau ; Evapotranspiration ; Humidité du sol ; Hydrologie ; Modèle ; Modèle conceptuel ; Méthodologie
Conceptual model ; Evapotranspiration ; Hydrology ; Methodology ; Model ; Soil moisture ; Water budget ; Water cycle
This paper firstly summarizes the evapotranspiration estimation methods applied in hydrological models and then classifies them into the integrated converting methods and the classification gathering methods by their mechanism. Integrated converting
methods are usually used in hydrological models and 2 differences exist among them : one is in the potential evaporation estimation methods, while the other is in the function for defining relationship between potential evaporation and actual
evapotranspiration. Different evapotranspiration calculation methods are used depending on the complexity of the hydrological model, and importance and difficulty in the selection of the most suitable evapotranspiration methods is discussed. Finally, this paper
points out the prospective development trends of the evapotranspiration estimating methods in hydrological modeling.
2013

Evaluation and application of Bayesian multi-model estimation in temperature simulations

Evaluation and application of Bayesian multi-model estimation in temperature simulations
Asie ; Australie ; Changement climatique ; Circulation atmosphérique ; Effet de serre ; Modèle ; Méthodologie ; Prévision ; Simulation ; Température
Asia ; Atmospheric circulation ; Australia ; Climatic change ; Forecast ; Greenhouse effect ; Methodology ; Model ; Simulation ; Temperature
This paper assesses the performance of multi-model ensembles in simulating global land temperature from 1960 to 1999, using Nash-Sutcliffe model efficiency and Taylor diagrams. The future trends of temperature for different scales and emission
scenarios are projected based on the posterior model probabilities estimated by Bayesian methods. The results show that ensemble prediction can improve the accuracy of simulations of the spatiotemporal distribution of global temperature. The performance
of Bayesian model averaging (BMA) at simulating the annual temperature dynamic is significantly better than single climate models and their simple model averaging (SMA). However, BMA simulation can demonstrate the temperature trend on the decadal scale
2013

Basin modelling of temperature and heat flow distributions and permafrost evolution, Urengoy and Kuyumbinskaya areas, Siberia

Basin modelling of temperature and heat flow distributions and permafrost evolution, Urengoy and Kuyumbinskaya areas, Siberia
Flux thermique ; Modèle ; Modèle numérique ; Paléoclimat ; Pergélisol ; Périglaciaire ; Russie d'Asie ; Sibir' ; Température ; Zone froide
Asian part of Russia ; Cold area ; Heat flow ; Model ; Numerical model ; Palaeoclimate ; Periglacial features ; Permafrost ; Siberia ; Temperature
The thermal history and permafrost evolution in the Urengoy area of the West Siberian basin and in the Kuyumbinskaya area of the Siberian platform during the Pliocene-Quaternary were reconstructed numerically in a forward model from 3.4 Ma using
the software package FROST, part of the basin modelling system GALO. Calculations suggest that variations in rock composition with depth strongly influenced permafrost evolution. The effect of cooling is greater in the Kuyumbinskaya area, which has a thinner
sedimentary cover, than in the more northern Urengoy area. The model estimates permafrost depth and the stability zone of methane gas hydrate. An increase in salt content in porewater lowers the melting temperature of ice. The modelling demonstrates
2013

Incorporation of multi-scale spatial autocorrelation in soil moisture–landscape modeling

Incorporation of multi-scale spatial autocorrelation in soil moisture–landscape modeling
Autocorrélation spatiale ; Corée du Sud ; Distribution spatiale ; Dune ; Humidité du sol ; Littoral ; Modèle ; Méthode des moindres carrés ; Sindu ; Sol ; Surface de tendance
Coastal environment ; Dune ; Least squares method ; Model ; Soil ; Soil moisture ; South Korea ; Spatial autocorrelation ; Spatial distribution ; Trend surface
Based on soil, vegetation, and topographic data collected in the Sindu coastal dunefield in western Korea, this research developed 3 soil moisture–landscape models, each incorporating spatial autocorrelation (SAC) at fine, broad, and multiple scales
, respectively, into a non-spatial ordinary least squares (OLS) model. All of these spatially explicit models showed better performance than the OLS model. In particular, the best model was proved to be the one using spatial eigenvector mapping, a technique
that accounts for spatial structure at multiple scales simultaneously. It is highlighted that the conventional regression modeling may have a reduced predictive power in reality, in cases where they possess a significant amount of SAC. This research demonstrates
2013

Dust emission in northern China : atmospheric emission–dispersion modelling of a major dust event

Dust emission in northern China : atmospheric emission–dispersion modelling of a major dust event
Alashan ; Chine ; Désert ; Eolien ; Modèle ; Modèle numérique ; Nei Menggu ; Tempête de poussière ; Télédétection
Aeolian features ; China ; Desert ; Dust storm ; Inner Mongolia ; Model ; Numerical model ; Remote sensing
The AA. propose a simulation system that integrates 3 different models in order to represent the whole dust cycle. The RAMS atmospheric model configuration has 2 nested grids, at 50 km and 10 km horizontal resolution, and is used to force both
the dust emission model DUSTEM, and the transport model CAMx. The performance of the three-model simulation system was evaluated using a major dust storm that occurred in March 2002 in the desert of the Alashan Prefecture (Inner Mongolia, China) and which
in the modelling system. Simulated dust storm features, from the higher resolution grid, are in good agreement with observed data. This integrated numerical model, along with the remote sensed land surface characterization, is suggested to be a practical
2013

Areal interpolation and dasymetric modeling. Special issue

Areal interpolation and dasymetric modeling. Special issue
Cartographie dasymétrique ; Estimation ; Interpolation de surface ; Modèle ; Modélisation ; Peuplement ; Pondération spatiale
Areal interpolation ; Estimation ; Model ; Modelling ; Settlement ; Spatial weighting
Six articles. 1. Les densités de Muncie (Indiana) et de Manhattan n'ont pas de commune mesure : utiliser la pondération géographique dans l'algorithme prévision-maximisation pour une interpolation de surface. 2. Un modèle d'interpolation de surface
2013

Theoretical principles in interurban simulation models : a comparison

Theoretical principles in interurban simulation models : a comparison
This article analyses the theoretical principles in interurban simulation models. To this end, it compares models made of systems of differential equations multi-agent models designed to simulating the differentiated dynamics of urban entities over
the medium to long term from their functional economic specialization. It shows that the latter systems are providing interesting solutions for the modelling method, because of their greater ability to simulate the emergence of geographical macrostructures
2013

Present climate and climate change over North America as simulated by the fifth-generation Canadian regional climate model

Present climate and climate change over North America as simulated by the fifth-generation Canadian regional climate model
Amérique du Nord ; Changement climatique ; Différenciation saisonnière ; Différenciation spatiale ; Modèle ; Modèle de climat régional ; Précipitation ; Simulation ; Siècle 21 ; Température
Climatic change ; Model ; North America ; Precipitation ; Simulation ; Spatial differentiation ; Temperature ; Twenty-first century
Le modèle climatique régional canadien de 5ème génération, qui a donné une simulation très réaliste de la période 1850-2005, laisse entrevoir pour les années 2006-2100 un réchauffement d'ensemble (surtout marqué en hiver aux latitudes élevées) et de
2013

A unified model for dispersing facilities

A unified model for dispersing facilities
Analyse spatiale ; Diffusion ; Equipement ; Modèle ; Service ; Structure spatiale
Diffusion ; Facilities ; Model ; Service ; Spatial analysis ; Spatial structure
On recense quatre formes de base pour le problème de la p-dispersion des équipements. On explore une autre hypothèse trouvée dans les quatre modèles classiques. Cependant, en réalité, il est plus logique de mesurer la dispersion par rapport à des
on montre que ce sont des formes généralisées des quatre modèles classiques présentés par Erkut et Neuman.
2013

Identification and estimation of club convergence models with spatial dependence

Identification and estimation of club convergence models with spatial dependence
Analyse spatiale ; Convergence ; Croissance économique ; Dépendance spatiale ; Economie régionale ; Italie ; Maximisation de l'entropie ; Modèle ; Niveau de vie ; Retombées
Convergence ; Economic growth ; Entropy maximization ; Italy ; Living standard ; Model ; Regional economy ; Spatial analysis ; Spatial dependence ; Spillover
Hétérogénéité et dépendance spatiale dans l'analyse de la croissance économique à l'aide d'une stratégie en deux étapes qui identifie des clubs par une analyse cartographique et estime un modèle de convergence de club avec dépendance spatiale
. On pose les problèmes d'identification et de colinéarité, et on développe une méthode d'estimation basée sur l'entropie qui prend en compte les problèmes d'inférence mal posés et mal conditionnés. On estime un modèle de convergence spatiale de deux clubs
2013

A simple model for the transport of soil-dissolved chemicals in runoff by raindrops

A simple model for the transport of soil-dissolved chemicals in runoff by raindrops
Charge en solution ; Chine ; Erosion des sols ; Erosion hydrique ; Loess ; Modèle ; Plateau ; Ruissellement ; Shaanxi ; Splash ; Transport sédimentaire
China ; Loess ; Model ; Plateau ; Rill wash ; Sediment transport ; Shaanxi ; Soil erosion ; Solution load ; Splash ; Water erosion
The development of a physically based model to simulate the transport of soil solutes in runoff has provided a better understanding of the mechanisms of transport and has assisted in the development of effective methods to control nutrient loss from
soils and the pollution of waterways. Assuming that the exchange rate is controlled by raindrop splash, the AA. neglected the effects of diffusion. To calibrate their model, laboratory experiments were conducted on disturbed loessial soil with 3 initial
soil-moisture contents under 3 rainfall intensities and 3 slope gradients. The model's simulated data agreed well with the experimental data, demonstrating that the refined model captured the temporal behaviour of solute transport in the runoff
. This study provides a new approach to the modelling of chemical transport by investigating the effects of raindrops on sediments from soil in surface runoff.
2013

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