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Coalbed methane development has proliferated across much of the western United States. Campbell County, Wyoming, in the Powder River Basin is one area that has seem some of the highest amounts of this development, most of it occurring on land where the surface use is livestock grazing, resulting in conflicts over resource use. This thesis takes a grounded theory approach to understanding the meaning that the ranchers that operate on this land have attached to this development. In doing so, this paper argues that these ranchers form opinions and attitudes based on how CBM has affected “the ranching way of life” and not simply on the perceived opportunity for economic gain. It also argues that although objections...
A two-dimensional finite element model was used to simulate the groundwater recovery process under various surface mining situations. The simulation results were used to predict the rate at which soil settlement takes place. It was found that the groundwater recovery process is very fast immediately after mine closure and cessation of dewatering programmes; a significant part of mine land settlement can be measured at such times. This paper presents a method for deriving the relationship between the re-establishment of the natural groundwater regime to its equilibrium position as existed prior to the commencement of mining operations and mine spoil settlement.
Issues related to energy saving and pollution reduction are closely related. Their importance has increased in recent years and presents considerable academic and industrial challenges. They generally represent complex tasks of a considerable scale and comprehensive interactions. The methodology and concepts of Process Integration have been developing over last thirty years [1] and have been considerably expended to tackle these problems [2]. International conferences provide a good opportunity to review the state-of-the-art in this field. One of the most established and well known conference is PRES. The 13th Conference on “Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction...
This study proposes the use of several problems of unstable steady state convection with variable fluid density in a porous layer of infinite horizontal extent as two-dimensional (2-D) test cases for density-dependent groundwater flow and solute transport simulators. Unlike existing density-dependent model benchmarks, these problems have well-defined stability criteria that are determined analytically. These analytical stability indicators can be compared with numerical model results to test the ability of a code to accurately simulate buoyancy driven flow and diffusion. The basic analytical solution is for a horizontally infinite fluid-filled porous layer in which fluid density decreases with depth. The proposed...
In this paper, I analyze an oligopoly model of exhaustible resource extraction and develop predictions about relative extraction patterns of different producers. Using the ‘oil’igopoly model of bury (Internat. Econom. Rev. 27, 285-301 (1986)), one can show that producers with large stocks produce a larger amount, but a smaller percentage, of their stocks than producers with small stocks. I extend Lomy’s model to cases where extraction costs differ among producers and where costs are a function of cumulative extraction. An increase in extraction costs for a producer causes it to produce less relative to its rivals. When extraction costs rise with cumulative extraction, producers with large reserves tend to have lower...
A two-dimensional finite element model was used to simulate the groundwater recovery process under various surface mining situations. The simulation results were used to predict the rate at which soil settlement takes place. It was found that the groundwater recovery process is very fast immediately after mine closure and cessation of dewatering programmes; a significant part of mine land settlement can be measured at such times. This paper presents a method for deriving the relationship between the re-establishment of the natural groundwater regime to its equilibrium position as existed prior to the commencement of mining operations and mine spoil settlement.
In this paper we introduce a comprehensive model for policy analysis of the greenhouse effect (PAGE). We apply the PAGE model to assess the merits of policies to prevent global warming (by controlling the emissions of greenhouse gases), and policies to adapt to any global warming that occurs. The results confirm that it is difficult to overcome the problem of global warming by taking preventive action alone. The argument for introducing an aggressive adaptive policy is very strong. We calculate the valuation that would have to be placed upon non-economic environmental and social impacts, for a combined strategy of preventive and adaptive policies to be considered a worthwhile option, both for individual regions...
Most regional ocean models that use discharge as part of the forcing use relatively coarse river discharge data sets (1°, or ∼110 km) compared to the model resolution (typically 1/4° or less), and do not account for seasonal changes in river water temperature. We introduce a new climatological data set of river discharge and river water temperature with 1/6° grid spacing over the Arctic region (Arctic River Discharge and Temperature; ARDAT), incorporating observations from 30 Arctic rivers. The annual mean discharge for all rivers in ARDAT is 2817 ± 330 km3 yr−1. River water temperatures range between 0 °C in winter to 14.0–17.6 °C in July, leading to a long-term mean monthly heat flux from all rivers of 3.2 ± 0.6...
In northern peatlands, subsurface ice formation is an important process that can control heat transport, groundwater flow, and biological activity. Temperature was measured over one and a half years in a vertical profile in the Red Lake Bog, Minnesota. To successfully simulate the transport of heat within the peat profile, the U.S. Geological Survey’s SUTRA computer code was modified. The modified code simulates fully saturated, coupled porewater-energy transport, with freezing and melting porewater, and includes proportional heat capacity and thermal conductivity of water and ice, decreasing matrix permeability due to ice formation, and latent heat. The model is verified by correctly simulating the Lunardini analytical...
In semiarid complex terrain, the landscape creates spatial niches for different types of vegetation through the effects of aspect, slope and curvature on the water and energy balance at the soil surface. The ecohydrology of rangelands is defined by the interaction of soils, plants and climate occurring on a topographic surface. While these interactions have been studied for subtle terrain, little is known about the controls exerted by terrain position, in particular terrain aspect, on ecosystem processes. Furthermore, differential plant establishment can lead to measurable differences in rates of soil development, which in turn can affect soil hydraulic properties and the surface water balance. In this study, we...
Most regional ocean models that use discharge as part of the forcing use relatively coarse river discharge data sets (1°, or ∼110 km) compared to the model resolution (typically 1/4° or less), and do not account for seasonal changes in river water temperature. We introduce a new climatological data set of river discharge and river water temperature with 1/6° grid spacing over the Arctic region (Arctic River Discharge and Temperature; ARDAT), incorporating observations from 30 Arctic rivers. The annual mean discharge for all rivers in ARDAT is 2817 ± 330 km3 yr−1. River water temperatures range between 0 °C in winter to 14.0–17.6 °C in July, leading to a long-term mean monthly heat flux from all rivers of 3.2 ± 0.6...
Abstrac As a pilot study potential biophysical and human land use drivers in Costa Rica were evaluated using multi-variate statistical methods in a nested scale analysis. The reconstructed land use drivers and their quantified effects on land use were applied within a dynamic framework CLUE (Conversion of Land Use and its Effects) to model land use dynamics in Costa Rica from 1973 to 1984. Our pilot study demonstrates that a land use/cover system can be described as a scale-dependent hierarchical system and that its dynamics can be satisfactorily modelled as functions of biophysical and human drivers.
Energy consumption from the residential sector is a complex socio-technical problem that can be explained using a combination of physical, demographic and behavioural characteristics of a dwelling and its occupants. A structural equation model (SEM) is introduced to calculate the magnitude and significance of explanatory variables on residential energy consumption. The benefit of this approach is that it explains the complex relationships that exist between manifest variables and their overall effect though direct, indirect and total effects. Using the English House Condition Survey (EHCS) consisting of 2531 unique cases, the main drivers behind residential energy consumption are found to be the number of household...
Recently, an active debate has emerged around greenhouse gas emissions due to indirect land use change (iLUC) of expanding agricultural areas dedicated to biofuel production. In this paper we provide a detailed analysis of the iLUC effect, and further address the issues of deforestation, irrigation water use, and crop price increases due to expanding biofuel acreage. We use GLOBIOM – an economic partial equilibrium model of the global forest, agriculture, and biomass sectors with a bottom-up representation of agricultural and forestry management practices. The results indicate that second generation biofuel production fed by wood from sustainably managed existing forests would lead to a negative iLUC factor, meaning...
Categories: Publication; Types: Citation; Tags: Biofuels, Land use change, Modelling
Integrated assessment models of global environmental problems play an increasingly important role in decision making. This use demands a good insight regarding the reliability of these models. In this paper we analyze uncertainty management in the IMAGE-project (Integrated Model to Assess the Greenhouse Effect). We use a classification scheme comprising type and source of uncertainty. Our analysis shows reliability analysis as main area for improvement. We briefly review a recently developed methodology, NUSAP, that systematically addresses the strength of data in terms of spread, reliability and scientific status (pedigree) of information. This approach is being tested through interviews with model builders.
Wind power forecasts are in various ways valuable for users in decision-making processes. However, most forecasts are deterministic, and hence possibly important information about uncertainty is not available. Complete information about future production can be obtained by using probabilistic forecasts, and this article demonstrates how such forecasts can be created by means of local quantile regression. The approach has several advantages, such as no distributional assumptions and flexible inclusion of predictive information. In addition, it can be shown that, for some purposes, forecasts in terms of quantiles provide the type of information required to make optimal economic decisions. The methodology is applied...
The stable isotopic composition of water is routinely used as a tracer to study water exchange processes in vascular plants and ecosystems. To date, no study has focussed on isotope processes in non-vascular, poikilohydric organisms such as lichens and bryophytes. To understand basic isotope exchange processes of non-vascular plants, thallus water isotopic composition was studied in various green-algal lichens exposed to desiccation. The study indicates that lichens equilibrate with the isotopic composition of surrounding water vapour. A model was developed as a proof of concept that accounts for the specific water relations of these poikilohydric organisms. The approach incorporates first their variable thallus...
This report documents the various photovoltaic (PV) performance models and software developed and utilized by researchers at Sandia National Laboratories (SNL) in support of the Photovoltaics and Grid Integration Department. In addition to PV performance models, hybrid system and battery storage models are discussed. A hybrid system using other distributed sources and energy storage can help reduce the variability inherent in PV generation, and due to the complexity of combining multiple generation sources and system loads, these models are invaluable for system design and optimization. Energy storage plays an important role in reducing PV intermittency and battery storage models are used to understand the best...
A two-dimensional finite element model was used to simulate the groundwater recovery process under various surface mining situations. The simulation results were used to predict the rate at which soil settlement takes place. It was found that the groundwater recovery process is very fast immediately after mine closure and cessation of dewatering programmes; a significant part of mine land settlement can be measured at such times. This paper presents a method for deriving the relationship between the re-establishment of the natural groundwater regime to its equilibrium position as existed prior to the commencement of mining operations and mine spoil settlement.
Wildland fire is a global phenomenon, and a result of interactions between climate?weather, fuels and people. Our climate is changing rapidly primarily through the release of greenhouse gases that may have profound and possibly unexpected impacts on global fire activity. The present paper reviews the current understanding of what the future may bring with respect to wildland fire and discusses future options for research and management. To date, research suggests a general increase in area burned and fire occurrence but there is a lot of spatial variability, with some areas of no change or even decreases in area burned and occurrence. Fire seasons are lengthening for temperate and boreal regions and this trend should...