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Spatial Estimations Of Air Pollution In Street Canyons By Lidar Measurements, L. Matejicek, Jana Konradova Jul 2006

Spatial Estimations Of Air Pollution In Street Canyons By Lidar Measurements, L. Matejicek, Jana Konradova

International Congress on Environmental Modelling and Software

Air pollution of urban areas can be explored by direct monitoring, mathematical modeling and physical simulation in the wind tunnels. Complex analysis requires using of all mentioned approaches together. To integrate the data inputs and outputs, which include spatio-temporal interactions, the Geographic Information System (GIS) is used for database management and spatial analysis. The geodatabase is primarily developed to support spatial interpolations of LIDAR measurements in the street canyons. The LIDAR measurements provide the information about the distribution of pollutants in the points along the beam trajectories. As the examples, the sets of NO2 spatial measurements are performed in the …

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Development Of A National, Landuse-Based Water Balance Model For Australia, Wendy D. Welsh, D. G. Barratt, K. Ranatunga, L. A. Randall Jul 2006

Development Of A National, Landuse-Based Water Balance Model For Australia, Wendy D. Welsh, D. G. Barratt, K. Ranatunga, L. A. Randall

International Congress on Environmental Modelling and Software

Australia currently has no nation-wide comprehensive and consistent information on the spatial and temporal relationships between rainfall, evapotranspiration, drainage to groundwater and runoff to rivers. To estimate this information a simple modelling approach utilising existing data was sought. A review of existing models and their data requirements led to the development of a steady state Geographic Information System (GIS) based method driven by long-term average climate data and high resolution land cover and land use data. Mean annual and mean monthly runoff, evapotranspiration and drainage were modelled. Runoff results were evaluated against other published values where available and found to …

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An Optimal Control And Options Theory Approach To Forecasting And Managing Sustainable Systems, Y. Shastri, U. Diwekar Jul 2006

An Optimal Control And Options Theory Approach To Forecasting And Managing Sustainable Systems, Y. Shastri, U. Diwekar

International Congress on Environmental Modelling and Software

Sustainable management of the natural systems is essential in the presence of anthropogenic andnatural disasters. Fisher information based measure and hypothesis have been proposed to quantify the sustainabilityof natural systems, which are used in this work to formulate management objectives. Since uncertaintyis omnipresent in natural systems, its consideration is important. Real options theory deals extensively with therepresentation and forecasting of uncertainty. The options theory, with the Ito mean reverting process, is usedto represent uncertainty, and optimal control theory is used to derive time dependent decisions. The idea isimplemented on a three species predator-prey model. The results highlight the effect of …

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A Simulation Model Of Land-Use Change In The Lake Tahoe Basin Of California And Nevada, As Used In A Decision-Support System, Mark L. Hessenflow, David L. Halsing Jul 2006

A Simulation Model Of Land-Use Change In The Lake Tahoe Basin Of California And Nevada, As Used In A Decision-Support System, Mark L. Hessenflow, David L. Halsing

International Congress on Environmental Modelling and Software

The Tahoe Land-Use Change model is a stochastic, spatially explicit simulation of future land-use change—in particular, development and retirement of individual parcels—in the Lake Tahoe Basin of California and Nevada. The Federal, State, and regional management agencies responsible for the basin are revising and integrating their 20-year plans to meet various goals, including maintaining or improving several environmental (e.g., lake clarity, forest health) and socioeconomic (e.g., affordable housing) characteristics. To assist this effort, the model projects the long-term outcomes of land-use-management decisions, including those relating to existing and potential government regulations, development activities, and conservation practices. The model results are …

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Application Of An Artificial Neural Network For Analysis Of Subsurface Contamination At The Schuyler Falls Landfill, Ny, Lance E. Besaw, Donna M. Rizzo, P. J. Mouser Jul 2006

Application Of An Artificial Neural Network For Analysis Of Subsurface Contamination At The Schuyler Falls Landfill, Ny, Lance E. Besaw, Donna M. Rizzo, P. J. Mouser

International Congress on Environmental Modelling and Software

Current subsurface site characterization, plume delineation, remediation designs and monitoring network designs that rely on a limited, albeit large, number of sparsely collected data, tend to be expensive, cumbersome and frequently inadequate for solving multi-objective, long-term environmental management problems. We present a subsurface characterization methodology that integrates multiple types of data using a modified counterpropagation artificial neural network (ANN) to provide parameter estimates and delineate groundwater contamination at a leaking landfill. Apparent conductivity survey data and hydrochemistry data (i.e. heavy metals, BOD5,20, chloride concentration, etc.) are used to estimate the extent of subsurface contamination at the Schuyler Falls Landfill, located …

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An Operational Scheme For Dynamic Resource Management In Case Of Natural Disaster Events, Paolo Fiorucci, F. Gaetani, R. Minciardi, Antonio Sgorbissa Jul 2006

An Operational Scheme For Dynamic Resource Management In Case Of Natural Disaster Events, Paolo Fiorucci, F. Gaetani, R. Minciardi, Antonio Sgorbissa

International Congress on Environmental Modelling and Software

The management of the resources engaged in emergencies due to the occurrence of very intense natural events requires the acquisition and processing of a huge number of heterogeneous data. Such data, both of deterministic and random nature, generally refer to different spatial and temporal scales. Considering the three main frameworks in which a natural risk scenario can be classified (i.e., preventive, emergency, and post-emergency phases), risk assessment has to be followed by a decision-oriented phase, whose objective is the selection of the optimal actions to undertake, on the basis of the available information. In the paper, the conceptual scheme and …

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A Decision Support System For Energy Production From Renewable Resources: Logistics Aspects Of Sustainable Forest Biomass Collection, R. Minciardi, M. Robba, Roberto Sacile, F. Frombo, Fulvia Rosso Jul 2006

A Decision Support System For Energy Production From Renewable Resources: Logistics Aspects Of Sustainable Forest Biomass Collection, R. Minciardi, M. Robba, Roberto Sacile, F. Frombo, Fulvia Rosso

International Congress on Environmental Modelling and Software

The consequences of the use of traditional fossil fuels has led, in the last years, the European Union to promote and encourage the development and the use of renewable energies rather than the traditional ones. Energy production from forest biomass does not involve the CO2 increase in the atmosphere, contributing in this way to the duties assumed by the European Community during the International Conference of Kyoto (1997). The developed DSS, that is a generalization and the further research activity presented in a previous work by the same authors (Freppaz et al. [2004]), is based on the integration of Geographic …

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A Protocol For The Development, Evaluation And Application Of Environmental Models In Decision Making, Noha Gaber, Pasky Pascual, Gary Foley, Neil Stiber, Elsie Sunderland Jul 2006

A Protocol For The Development, Evaluation And Application Of Environmental Models In Decision Making, Noha Gaber, Pasky Pascual, Gary Foley, Neil Stiber, Elsie Sunderland

International Congress on Environmental Modelling and Software

Models have emerged as essential tools in environmental management, whether used to further the understanding of complex environmental processes or to inform decisions for environmental planning, remediation, protection or regulation. However, their utility aside, there is also an acknowledgment of their limitations. The question is not whether or not to use models, but rather how best to develop and use models to arrive at credible, defensible and robust decisions and what attributes make a model useful for a given situation. To understand the role of models and decision support tools in environmental management, we must first consider the different types …

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Spatial Estimations Of Air Pollution In Urban Areas By Lidar Measurements, L. Matejicek Jul 2006

Spatial Estimations Of Air Pollution In Urban Areas By Lidar Measurements, L. Matejicek

International Congress on Environmental Modelling and Software

Spatial analysis and visualization of data focused on air pollution in urban areas can be more efficiently explored by geographic information systems (GISs). Data originating from direct monitoring, mathematical modelling and physical simulation in wind tunnels are represented by a wide range of data formats that, together with spatial objects on the surface of studied areas, form heterogenic structures. Thus, to solve spatio-temporal analysis and numeric models, a complex computer system is needed to manage the data and a number of user oriented procedures. In the case of this contribution, a GIS project is developed to examine the GIS abilities …

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Model Averaging, Equifinality And Uncertainty Estimation In The Modelling Of Ungauged Catchments, J. P. C. Reichl, F. H. S. Chiew, A. W. Western Jul 2006

Model Averaging, Equifinality And Uncertainty Estimation In The Modelling Of Ungauged Catchments, J. P. C. Reichl, F. H. S. Chiew, A. W. Western

International Congress on Environmental Modelling and Software

The problem of estimating runoff in ungauged catchments remains an important but elusive one. Previous studies suggest that there are two important properties common to rainfall-runoff models: over-parameterisation, leading to parameter covariance; and equifinality, the existence of multiple parameter sets which reproduce the streamflow adequately. Both reduce parameter identifiability, impeding identification of relationships between model parameter values and catchment characteristics that would otherwise be useful for regionalisation. This study investigates the use of a model averaging framework to circumvent this problem. Multiple behavioural parameter sets arising from Monte-Carlo simulation are used from each catchment in order to retain information about …

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Numerical Simulation Of Flow And Tracer Transport In A Disinfection Contact Tank, C. Gualtieri Jul 2006

Numerical Simulation Of Flow And Tracer Transport In A Disinfection Contact Tank, C. Gualtieri

International Congress on Environmental Modelling and Software

Chlorine is extensively used to disinfect drinking water supply. However, the design of chlorine contact tank is usually based on the volume displacement criterion, paying attention that detention time would be at least of half an hour. This criterion relies upon the assumption that plug-flow conditions hold along the tank. However, the existence and arrangement of baffles in the tank, and the tank inlet and outlet configurations can result in a much more complex flow pattern, where turbulent mixing, dead-zones and short-circuiting exist. This situation could result in an inefficient use of chlorine due to the formation of potentially carcinogenic …

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Hydrological Characterisation Of Four Brazilian Catchments Using A Simple Rainfall-Streamflow Model, I. G. Littlewood, R. T. Clarke, W. Collischonnb, B. F. W. Croke Jul 2006

Hydrological Characterisation Of Four Brazilian Catchments Using A Simple Rainfall-Streamflow Model, I. G. Littlewood, R. T. Clarke, W. Collischonnb, B. F. W. Croke

International Congress on Environmental Modelling and Software

A rainfall–streamflow model featuring a unit hydrograph component is applied to four Brazilian catchments to characterise and quantify their quite different dynamic rainfall–streamflow behaviours. Using only catchment size (km2) and time series of daily rainfall, streamflow and air temperature, six dynamic response characteristics (DRCs) are estimated for each catchment. The DRCs include decay time constants for dominant quick- and slow-response components of streamflow, a time-averaged relative volumetric contribution to streamflow from slow flow (i.e. a slow flow index, SFI) and the size of a conceptual catchment wetness store. The six DRCs are compared for the four catchments in the context …

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E2sp. The Business Case Of An Environmental Information System In Asp Mode., M. Cislaghi, G. Corbetta, R. Mazzilli, F. Scanzani, M. Caselli, L. Trizio, C. Derognat, R. Dunal, K. Klejnowski, A. Bucko-Serafin Jul 2006

E2sp. The Business Case Of An Environmental Information System In Asp Mode., M. Cislaghi, G. Corbetta, R. Mazzilli, F. Scanzani, M. Caselli, L. Trizio, C. Derognat, R. Dunal, K. Klejnowski, A. Bucko-Serafin

International Congress on Environmental Modelling and Software

According to PSR (OECD) and DPSIR (EEA) models, environmental agencies are in charge of measuring the State and Pressure and evaluate the Impact in order to define the most suitable Responses; this implies data analysis and reporting activities, as one of their core responsibilities. Environmental Information Systems support these activities by combining the advantages of first-rate consolidated technology (such as Business Intelligence and Data Warehouses) to specific technical architectures tailored to environmental management tasks. E2SP (Environmental Enterprise Service Provider) is a online reporting and forecasting platform, providing a cost effective, Internet based Environmental Information System and Decision Support System in …

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A New Raster-Based Spatial Modelling System: 5d Environment, S. Mazzoleni, F. Giannino, M. Mulligan, D. Heathfield, M. Colandrea, M. Nicolazzo, M. D'Aquino Jul 2006

A New Raster-Based Spatial Modelling System: 5d Environment, S. Mazzoleni, F. Giannino, M. Mulligan, D. Heathfield, M. Colandrea, M. Nicolazzo, M. D'Aquino

International Congress on Environmental Modelling and Software

The functional description of natural systems requires the representation of different classes of processes including chemical, biochemical, and physical functions, with or without their spatial representation. On the other hand, there are several cases where a realistic representation of the process dynamics needs a spatially explicit implementation of the model (eg. hydrological flows, fire propagation, pollution diffusion, etc.). In more general terms, and for different scientific fields, scaling problems and the issue of linking dynamic and spatial processes require an integrated logic and appropriate software solutions. Different tools aimed at implementing spatial modelling capability (PCRaster, SME, SimARC) have not yet …

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Weap Water Evaluation And Planning System, Jack Sieber Jul 2006

Weap Water Evaluation And Planning System, Jack Sieber

International Congress on Environmental Modelling and Software

WEAP is a microcomputer tool for integrated water resources planning. It provides a comprehensive, flexible and user-friendly framework for policy analysis. A growing number of water professionals are finding WEAP to be a useful addition to their toolbox of models, databases, spreadsheets and other software. This introduction summarizes WEAPΥs purpose, approach and structure. A detailed technical description is available in a separate publication, the WEAP User Guide.

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Multiobjective Optimization Procedure For Control Strategies In Environmental Systems, Xavier Flores, Joaquim Comas, Ignasi Rodríguez-Roda, Laureano Jiménez, Rene Bañares-Alcántara Jul 2006

Multiobjective Optimization Procedure For Control Strategies In Environmental Systems, Xavier Flores, Joaquim Comas, Ignasi Rodríguez-Roda, Laureano Jiménez, Rene Bañares-Alcántara

International Congress on Environmental Modelling and Software

This paper presents a systematic procedure for multiobjective optimization of control strategies in environmental systems. The optimization of control strategies in environmental systems is a complex activity due to the large number of objectives that must be considered simultaneously e.g. economic, environmental, technical, legal. The accomplishment of those objectives generates significant synergies, but in many cases they are subject of clear trade-offs. This procedure is approached as a multicriteria decision analysis (MCDA) and involves the quantification and normalization of a set of evaluation criteria and a weighted sum. A sensitivity analysis is also included in order to show the variation …

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Intelligent Configuration Of Numerical Solvers Of Environmental Ode/Dae Models Using Machine Learning Techniques, Petra Claeys, Peter A. Vanrolleghem Jul 2006

Intelligent Configuration Of Numerical Solvers Of Environmental Ode/Dae Models Using Machine Learning Techniques, Petra Claeys, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

The models considered in this work contain combinations of a large number of non-linear differential equations and algebraic equations, which have to be solved numerically. Because of this, running simulation experiments on a computer can be very time-consuming, i.e. it can last for days or even weeks. On top of that, some solvers are not appropriate for solving certain of these systems. For example, stiff solvers are only appropriate for stiff systems while they are not the best choice for non-stiff systems. Choosing the appropriate solver and solver settings for a certain initialized model can significantly shorten the computation time. …

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Modeling Short-Term Epidemics And Intervention Strategies In Cities, Valeriy Perminov, M. Kornilina Jul 2006

Modeling Short-Term Epidemics And Intervention Strategies In Cities, Valeriy Perminov, M. Kornilina

International Congress on Environmental Modelling and Software

Individual-based model (IBM) for simulation of urban influenza epidemic is constructed. In comparison with the past similar models the proposed model has new features: 1)it bases on a real demographical and social infrastructure statistical data; 2)its contacts network is built up with the help of daily routines of different age and social groups of residents. Test simulations were carried out with the use of demographical data on the population of Dresden (Germany). The results obtained showed that the proposed model can be used for the simulation of different epidemics and intervention strategies to contain epidemic or to weaken its consequences.

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Construction Of A Degree-Day Snow Model In The Light Of The Ten Iterative Steps In Model Development, Teemu Kokkonen, Harri Koivusalo, Tony Jakeman, J. P. Norton Jul 2006

Construction Of A Degree-Day Snow Model In The Light Of The Ten Iterative Steps In Model Development, Teemu Kokkonen, Harri Koivusalo, Tony Jakeman, J. P. Norton

International Congress on Environmental Modelling and Software

Jakeman et al. (2005) discuss minimum standards for model development and reporting and offer an outline of ten iterative steps to be used in model development. They present the main steps and give examples of what each step might include (especially what choices are to be made), without attempting the formidable task of compiling a comprehensive check list of the model-development process. This study reports construction of a simple degree-day snowmelt model in the light of the ten iterative steps. Such a modelling approach has been widely used in operational hydrology, where the motivation is to produce as reliable as …

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Rank-Equivalence Method For Sensitivity Analysis Of An Integrated Model Of A River Catchment, J. K. Ravalico, Graeme C. Dandy, Holger R. Maier Jul 2006

Rank-Equivalence Method For Sensitivity Analysis Of An Integrated Model Of A River Catchment, J. K. Ravalico, Graeme C. Dandy, Holger R. Maier

International Congress on Environmental Modelling and Software

Integrated Assessment Modelling (IAM) incorporates knowledge from different disciplines to provide an overarching assessment of the impact of different management decisions. Integrated models generally require numerous parameters from varying sources, many not known with certainty. Rapid increases in model size and complexity, particularly in the case of integrated models for decision-making, pose new challenges for effective sensitivity analysis. Some of the identified shortcomings of existing sensitivity analysis methods in the context of IAM include: computational inefficiency, failure to assess parameter interactions, excessive data requirements (e.g. requiring parameter probability distributions), assumptions of model linearity and monotonicity and, in particular, difficulty of …

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Supporting Environmental And Energy Decisions Through An Open Software Structure, Giorgio Guariso, Matteo Baracani Jul 2006

Supporting Environmental And Energy Decisions Through An Open Software Structure, Giorgio Guariso, Matteo Baracani

International Congress on Environmental Modelling and Software

Public participation to environmental planning and management decisions, as suggested by localAgenda 21 processes, can be supported by software tools developed with a cyclic interaction with all thestakeholders and simple enough to be quickly operated by a large set of heterogeneous users. This also helpspreventing their rapid aging and their excessive dependence on changing technologies. We experimented thedevelopment of such software tools using an Office type environment to store data, analyse, andgeographically represent the effects of alternative decisions and html files to help utilizing the software anddistributing the information over the Internet. Two different applications are reported in the paper. …

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Prorank A Software Tool Used For The Evaluation Of Environmental Databases, S. Pudenz, Rainer Brüggemann, K. Voigt Jul 2006

Prorank A Software Tool Used For The Evaluation Of Environmental Databases, S. Pudenz, Rainer Brüggemann, K. Voigt

International Congress on Environmental Modelling and Software

On one hand a lot of research has been performed and an enormous amount of data generated concerning protection of human health and the environment with respect to chemical substances. On the other hand great data gaps for environmental chemicals have been detected in the run-up to a new chemicals policy in the EU, known under the name of REACH. In our approach we elucidate the data availability on chemicals applying the Hasse Diagram Technique (HDT) which originates in discrete mathematics as an environmetrical and chemometrical method. The software package used is ProRank software for multi-criteria evaluation and decision support …

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Uncertainty Management, Spatial And Temporal Reasoning, And Validation Of Intelligent Environmental Decision Support Systems, Miquel Sànchez-Marrè, Karina Gibert, Rick Sojda, Jean-Philippe Steyer, Peter Struss, Ignasi Rodríguez-Roda Jul 2006

Uncertainty Management, Spatial And Temporal Reasoning, And Validation Of Intelligent Environmental Decision Support Systems, Miquel Sànchez-Marrè, Karina Gibert, Rick Sojda, Jean-Philippe Steyer, Peter Struss, Ignasi Rodríguez-Roda

International Congress on Environmental Modelling and Software

There are inherent open problems arising when developing and running Intelligent Environmental Decision Support Systems (IEDSS). During daily operation of IEDSS several open challenge problems appear. The uncertainty of data being processed is intrinsic to the environmental system, which is being monitored by several on-line sensors and off-line data. Thus, anomalous data values at data gathering level or even uncertain reasoning process at later levels such as in diagnosis or decision support or planning can lead the environmental process to unsafe critical operation states. At diagnosis level or even at decision support level or planning level, spatial reasoning or temporal …

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Avoiding The Finite Difference Sensitivity Analysis Deathtrap By Using The Complex-Step Derivative Approximation Technique, Dirk J. W. De Pauw, Peter A. Vanrolleghem Jul 2006

Avoiding The Finite Difference Sensitivity Analysis Deathtrap By Using The Complex-Step Derivative Approximation Technique, Dirk J. W. De Pauw, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

In this paper, the complex-step derivative approximation technique will be used for calculating local sensitivity functions. This technique is compared to the finite difference approximation, probably the most used local sensitivity analysis technique. For this comparison, 4 biotechnological models with varying model complexity were used. A well known problem of the finite difference approximation is the choice of a suitable perturbation factor in order to avoid non-linear model effects or numerical errors due to the subtraction of almost equal numbers. The main advantage of the complex-step derivative approximation technique is that it is not susceptible to errors introduced by small …

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Neural Identification Of Fuzzy Anomalies In Pressurized Water Systems, Joaquín Izquierdo, R. Pérez, P. A. López, P. L. Iglesias Jul 2006

Neural Identification Of Fuzzy Anomalies In Pressurized Water Systems, Joaquín Izquierdo, R. Pérez, P. A. López, P. L. Iglesias

International Congress on Environmental Modelling and Software

The objective of a Water Supply System (WSS) is to convey treated water to consumers through a pressurized network of pipes. A number of meters and gauges are used to take continuous or periodic measurements that are sent via a telemetry system to the control and operation centre and used to monitor the network. Using this typically limited number of measures together with demand predictions the state of the system must be assessed. Suitable state estimation is of paramount importance in diagnosing leaks and other anomalies in WSS. But this task can be really cumbersome, if not unattainable, for human …

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Non-Linear, Multivariate Forecasting Of Hydrologic And Anthropogenic Responses To Meteorological Forcing, Edwin Roehl, Terry Murray Jul 2006

Non-Linear, Multivariate Forecasting Of Hydrologic And Anthropogenic Responses To Meteorological Forcing, Edwin Roehl, Terry Murray

International Congress on Environmental Modelling and Software

Managers and users of natural resources often face two challenging problems. One is forecasting future natural system conditions for optimal resource allocation. Here, the natural system is comprised of the weather and a dependant hydrologic system that contains a water resource. The second problem is forecasting the behavior of a combined natural and man-made system, which also includes anthropogenic resource consumers. Even though detailed meteorological forecasting over weeks and months is impractical, hydrologic behaviors such as groundwater cycling can transpire over months and years. Alternatively, man-made systems exhibit behaviors that both lag and lead causal forcing, e.g., seasonal weather changes. …

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A Framework For Spatio-Temporal Data Analysis And Hypothesis Exploration, Alexander Campbell, Binh Pham, Yu-Chu Tian Jul 2006

A Framework For Spatio-Temporal Data Analysis And Hypothesis Exploration, Alexander Campbell, Binh Pham, Yu-Chu Tian

International Congress on Environmental Modelling and Software

We present a general framework for pattern discovery and hypothesis exploration in spatio-temporaldata sets that is based on delay-embedding. This is a remarkable method of nonlinear time-series analysis thatallows the full phase-space behaviour of a system to be reconstructed from only a single observable (accessiblevariable). Recent extensions to the theory that focus on a probabilistic interpretation extend its scope and allowpractical application to noisy, uncertain and high-dimensional systems. Our framework uses these extensions toaid alignment of spatio-temporal sub-models (hypotheses) to empirical data - for example, satellite images plusremote-sensing - and to explore behaviours consistent with this alignment. The novel aspect …

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Structure - Fate - Relationships Of Organic Chemicals, Rainer Brüggemann, Guillermo Restrepo, Kristina Voigt Jul 2006

Structure - Fate - Relationships Of Organic Chemicals, Rainer Brüggemann, Guillermo Restrepo, Kristina Voigt

International Congress on Environmental Modelling and Software

The evaluation of the potential risk of chemicals receives again a lot of interest due to the renewed chemicals’ policy in the EU. The model package E4CHEM (Exposure Estimation for Potentially Ecotoxic Environmental Chemicals), already developed 1984-1992, is presented in this paper. This is a model which on the one side needs less information or input parameters as the often applied EUSES (European Union System for the Evaluation of Substances) and on the other side provides modules, like EXWAT (Model for the behaviour of the chemical in rivers)) and DTEST (Automatic Data Estimation), which as such are not contained in …

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Consistency Versus Optimality In Environmental Model Identification Under Uncertainty, T. Wagener, P. Dornsife, M. Clark Jul 2006

Consistency Versus Optimality In Environmental Model Identification Under Uncertainty, T. Wagener, P. Dornsife, M. Clark

International Congress on Environmental Modelling and Software

Current model identification strategies often have the objective of finding the model or model structure which provides the best performance in reproducing the observed response of a system at hand. Such a strategy typically favours more complex (bottom-up) models with a higher degree of freedom and thus larger flexibility. While this bias can be reduced through punishing models for being more complex, real advancements in our understanding with respect to appropriate system representations are made if we quantify the extent to which our model is consistent with the available data. In particular the idea of an optimal parameter set is …

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Deriving A Spatially-Explicit Hillslope Sediment Delivery Ratio Model Based On The Travel Time Of Water Across A Hillslope, D. A. Post, A. E. Kinsey-Henderson, R. Bartley, A. Hawdon Jul 2006

Deriving A Spatially-Explicit Hillslope Sediment Delivery Ratio Model Based On The Travel Time Of Water Across A Hillslope, D. A. Post, A. E. Kinsey-Henderson, R. Bartley, A. Hawdon

International Congress on Environmental Modelling and Software

To derive a sediment budget at the catchment scale, sediment transport models such as SedNet typically require an estimate to be made of the input of sediment to each stream link for each defined sub-catchment. This requires an estimate of both the erosion and delivery of sediment from every pixel within each sub-catchment. The total erosion within each pixel is calculated using the Universal Soil Loss Equation (USLE), while the delivery of sediment from that pixel to the nearest stream is based on a hillslope delivery ratio (HSDR). At large scales (250 m), a constant HSDR is typically used, however …

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