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Using Optimization For Environmental Simulation Model Calibration Uncertainty Analysis, B. A. Tolson, C. A. Shoemaker
Using Optimization For Environmental Simulation Model Calibration Uncertainty Analysis, B. A. Tolson, C. A. Shoemaker
International Congress on Environmental Modelling and Software
Environmental simulation models areapproximations of reality, and are therefore allsubject to varying degrees of uncertainty. Ingeneral, uncertainty sources in environmentalmodeling include parameter, data and modelstructure. When the uncertainty of these modelinputs are quantified in terms of probabilitydistributions, a traditional Monte Carlopropagation of input uncertainty can be performed.However, this traditional approach becomes muchmore complicated when model calibration data isconsidered because the random input sets sampledfrom the joint parameter and input distributionsmust also be deemed to produce reasonablepredictions of the available measured calibrationdata. Two types of methods that were developedto cope with this complication are the GeneralizedLikelihood Uncertainty Estimation or GLUEmethodology (Beven …
Localization Effects Of Land Use Change On Hydrological Models, Sven Lautenbach, Alexey Voinov, Ralf Seppelt
Localization Effects Of Land Use Change On Hydrological Models, Sven Lautenbach, Alexey Voinov, Ralf Seppelt
International Congress on Environmental Modelling and Software
Semi-distributed hydrological models generally have the advantages of short calculation times, comparative low calibration needs and high model efficiency, but lack the ability to consider localization effects of land use change. A regionalisation of these models allows a sensitivity analysis of the localization effects. HBV-D, a conceptual hydrological model is used in this study. The regionalization for the German watershed Parthe (˜317 km2) is coded in the framework of SME (spatial modeling environment) which allows a fast grid based regionalization of the model. Additional complexity at the finer scale is handled by downscaling of calibration parameters fromthe semi-distributedmodel by using …
Practical Sensitivity And Uncertainty Analysis Techniques Applied To Agricultural System Models, James C. Ascough Ii
Practical Sensitivity And Uncertainty Analysis Techniques Applied To Agricultural System Models, James C. Ascough Ii
International Congress on Environmental Modelling and Software
A practical evaluation framework is presented for analysis of two complex, process-based agricultural system models, WEPP and RZWQM. The evaluation framework combines sensitivity analysis and the uncertainty analysis techniques of first order error analysis (FOA) and Monte Carlo simulation with Latin Hypercube Sampling (LHS). WEPP model runoff, soil loss, and corn (Zea Mays L.) yield output responses in the form of expected values and error variances were determined to illustrate model prediction uncertainty. Sensitivity analysis results show the WEPP model response for runoff to be most sensitive to effective hydraulic conductivity and soil parameters used in the crusting factor adjustment. …
Environmental Policy Aid Under Uncertainty, J. Myšiak, J. D. Brown
Environmental Policy Aid Under Uncertainty, J. Myšiak, J. D. Brown
International Congress on Environmental Modelling and Software
Uncertainty pervades all aspects of environmental policy making. Numerous typologies and techniques have been developed to conceptualise, classify, assess (qualitatively and quantitatively), propagate, control, reduce and communicate uncertainty. Such assessments are a necessary but insufficient condition for reducing uncertainty in environmental decision making. In this paper we discuss how uncertainty is translated into decisions. Since this entails numerous value judgements and trade-offs which are sensitive to how policy problems are framed, we argue that perceptions of uncertainty cannot be viewed independently of the (quality of) the policy process that it intends to inform. Thus, uncertainty management should not be limited …
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
International Congress on Environmental Modelling and Software
Canada is developing the National Forest Carbon Monitoring Accounting and Reporting System(NFCMARS) to meet international reporting obligations under the United Nations Framework Convention onClimate Change (UNFCCC) and the Kyoto Protocol. The system integrates information about forest area,age and species composition, growth rates, and natural and anthropogenic disturbances in a modelingframework that simulates the forest carbon cycle at stand and landscape scales. The system reports, atregional and national scales, the emissions and removals of greenhouse gases in Canada’s managed forests.Approaches to quantify the uncertainties associated with these estimates are being developed. Thedifficulties associated with meaningfully quantifying uncertainty for national-scale estimates of …
Current Trends In Environmental Modelling With Uncertainty., Jiří Hřebíček, Jan Pesl
Current Trends In Environmental Modelling With Uncertainty., Jiří Hřebíček, Jan Pesl
International Congress on Environmental Modelling and Software
The important characteristic feature of environmental modelling is the complexity and uncertainty of its mathematical representation (uncertainty of formula). Imprecision of its input data is another characteristic feature, where it is not possible to omit influences of primary monitoring (e.g. gaps of data, errors of measuring facilities, human factor, etc). Many parameters in algorithms and their mathematical formulations are substituted by empirical constants in praxis, although it is well known that their values are very volatile and input data are not validated. Nowadays, information and communication technology (ICT) capabilities are growing rapidly and applied mathematical software (e.g. computer algebra systems, …
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
International Congress on Environmental Modelling and Software
Canada is developing the National Forest Carbon Monitoring Accounting and Reporting System(NFCMARS) to meet international reporting obligations under the United Nations Framework Convention onClimate Change (UNFCCC) and the Kyoto Protocol. The system integrates information about forest area,age and species composition, growth rates, and natural and anthropogenic disturbances in a modelingframework that simulates the forest carbon cycle at stand and landscape scales. The system reports, atregional and national scales, the emissions and removals of greenhouse gases in Canada’s managed forests.Approaches to quantify the uncertainties associated with these estimates are being developed. Thedifficulties associated with meaningfully quantifying uncertainty for national-scale estimates of …
Using Optimization For Environmental Simulation Model Calibration Uncertainty Analysis, B. A. Tolson, C. A. Shoemaker
Using Optimization For Environmental Simulation Model Calibration Uncertainty Analysis, B. A. Tolson, C. A. Shoemaker
International Congress on Environmental Modelling and Software
Environmental simulation models areapproximations of reality, and are therefore allsubject to varying degrees of uncertainty. Ingeneral, uncertainty sources in environmentalmodeling include parameter, data and modelstructure. When the uncertainty of these modelinputs are quantified in terms of probabilitydistributions, a traditional Monte Carlopropagation of input uncertainty can be performed.However, this traditional approach becomes muchmore complicated when model calibration data isconsidered because the random input sets sampledfrom the joint parameter and input distributionsmust also be deemed to produce reasonablepredictions of the available measured calibrationdata. Two types of methods that were developedto cope with this complication are the GeneralizedLikelihood Uncertainty Estimation or GLUEmethodology (Beven …
Localization Effects Of Land Use Change On Hydrological Models, Sven Lautenbach, Alexey Voinov, Ralf Seppelt
Localization Effects Of Land Use Change On Hydrological Models, Sven Lautenbach, Alexey Voinov, Ralf Seppelt
International Congress on Environmental Modelling and Software
Semi-distributed hydrological models generally have the advantages of short calculation times, comparative low calibration needs and high model efficiency, but lack the ability to consider localization effects of land use change. A regionalisation of these models allows a sensitivity analysis of the localization effects. HBV-D, a conceptual hydrological model is used in this study. The regionalization for the German watershed Parthe (˜317 km2) is coded in the framework of SME (spatial modeling environment) which allows a fast grid based regionalization of the model. Additional complexity at the finer scale is handled by downscaling of calibration parameters fromthe semi-distributedmodel by using …
Practical Sensitivity And Uncertainty Analysis Techniques Applied To Agricultural System Models, James C. Ascough Ii
Practical Sensitivity And Uncertainty Analysis Techniques Applied To Agricultural System Models, James C. Ascough Ii
International Congress on Environmental Modelling and Software
A practical evaluation framework is presented for analysis of two complex, process-based agricultural system models, WEPP and RZWQM. The evaluation framework combines sensitivity analysis and the uncertainty analysis techniques of first order error analysis (FOA) and Monte Carlo simulation with Latin Hypercube Sampling (LHS). WEPP model runoff, soil loss, and corn (Zea Mays L.) yield output responses in the form of expected values and error variances were determined to illustrate model prediction uncertainty. Sensitivity analysis results show the WEPP model response for runoff to be most sensitive to effective hydraulic conductivity and soil parameters used in the crusting factor adjustment. …
Environmental Policy Aid Under Uncertainty, J. Myšiak, J. D. Brown
Environmental Policy Aid Under Uncertainty, J. Myšiak, J. D. Brown
International Congress on Environmental Modelling and Software
Uncertainty pervades all aspects of environmental policy making. Numerous typologies and techniques have been developed to conceptualise, classify, assess (qualitatively and quantitatively), propagate, control, reduce and communicate uncertainty. Such assessments are a necessary but insufficient condition for reducing uncertainty in environmental decision making. In this paper we discuss how uncertainty is translated into decisions. Since this entails numerous value judgements and trade-offs which are sensitive to how policy problems are framed, we argue that perceptions of uncertainty cannot be viewed independently of the (quality of) the policy process that it intends to inform. Thus, uncertainty management should not be limited …
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
International Congress on Environmental Modelling and Software
Canada is developing the National Forest Carbon Monitoring Accounting and Reporting System(NFCMARS) to meet international reporting obligations under the United Nations Framework Convention onClimate Change (UNFCCC) and the Kyoto Protocol. The system integrates information about forest area,age and species composition, growth rates, and natural and anthropogenic disturbances in a modelingframework that simulates the forest carbon cycle at stand and landscape scales. The system reports, atregional and national scales, the emissions and removals of greenhouse gases in Canada’s managed forests.Approaches to quantify the uncertainties associated with these estimates are being developed. Thedifficulties associated with meaningfully quantifying uncertainty for national-scale estimates of …
Current Trends In Environmental Modelling With Uncertainty., Jiří Hřebíček, Jan Pesl
Current Trends In Environmental Modelling With Uncertainty., Jiří Hřebíček, Jan Pesl
International Congress on Environmental Modelling and Software
The important characteristic feature of environmental modelling is the complexity and uncertainty of its mathematical representation (uncertainty of formula). Imprecision of its input data is another characteristic feature, where it is not possible to omit influences of primary monitoring (e.g. gaps of data, errors of measuring facilities, human factor, etc). Many parameters in algorithms and their mathematical formulations are substituted by empirical constants in praxis, although it is well known that their values are very volatile and input data are not validated. Nowadays, information and communication technology (ICT) capabilities are growing rapidly and applied mathematical software (e.g. computer algebra systems, …
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
Quantifying Uncertainties Associated With Estimates Of Greenhouse Gas Emissions And Removals From Canada’S Managed Forests, Thomas White, Werner Kurz, Graham Stinson
International Congress on Environmental Modelling and Software
Canada is developing the National Forest Carbon Monitoring Accounting and Reporting System(NFCMARS) to meet international reporting obligations under the United Nations Framework Convention onClimate Change (UNFCCC) and the Kyoto Protocol. The system integrates information about forest area,age and species composition, growth rates, and natural and anthropogenic disturbances in a modelingframework that simulates the forest carbon cycle at stand and landscape scales. The system reports, atregional and national scales, the emissions and removals of greenhouse gases in Canada’s managed forests.Approaches to quantify the uncertainties associated with these estimates are being developed. Thedifficulties associated with meaningfully quantifying uncertainty for national-scale estimates of …