Computer Engineering Commons^™

A New Framework For Global Sensitivity Analysis For Environmental Modelling, Saman Razavi, Hoshin Gupta, Amin Haghnegahdar, Razi Sheikholeslami

International Congress on Environmental Modelling and Software

Global sensitivity analysis (GSA) is an effective tool for understanding the role and functioning of different model factors (e.g., model parameters, forcings, and boundary and initial conditions) in generating the model response. GSA can be helpful to improve the credibility and utility of environmental systems models, as these models are continually growing in complexity and dimensionality with continuous advances in understanding and computing power. However, conventional approaches to GSA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we identify several important sensitivity-related characteristics of response surfaces that must …

Exploring Socio-Hydrological Dynamics With A Hybrid Hydrological Agent-Based Model, Anastasia Lobanova, Francesco Lamperti, Andrea Roventini, David Tabara, Stefan Liersch, Valentina Krysanova

International Congress on Environmental Modelling and Software

The rivers cannot be anymore analyzed as solely natural systems, because their hydrological dynamics is defined to a greater extent by strategic human decisions and management to meet social and economic water demands. The necessity of coupling local social dynamics with hydrological processes for river catchments analysis is around for a decade and more and more authors are speaking about the concept of human-natural systems and the ways to investigate their mutual effects dynamically. Following this idea, the studies on the impacts of climatic change on the hydrological systems has to incorporate the mutual effects of the socio-hydrological system to …

Local And Regional Contributions To Nitrogen Dioxide, Tim Oxley, Helen Apsimon, Rosalind O’Driscoll

International Congress on Environmental Modelling and Software

An important application of models is source apportionment, distinguishing the contribution of different sources to pollutant concentrations at critical locations - something which is difficult to deduce from measurements. As illustrated in this paper the UK Integrated Assessment Model (UKIAM) has been developed with this in mind, with a facility to produce a detailed breakdown of source contributions, indicating clearly the sources to be targeted for abatement and where uncertainties and sensitivity studies may be most important. “Impact factors”, defined as the change in concentration/exposure per unit reduction in emission for each source, are also useful in development of effective …

Hydrological Water Resources Assessment Of Cega-Eresma-Adaja Watershed System Using Swat Model, David A. Rivas, Angel De Miguel, Bárbara Willarts

International Congress on Environmental Modelling and Software

In the hydrological assessment of water bodies, modeling is a key fact in water management strategies of watersheds and serves as a tool for decision making considering environmental issues as the core of sustainable development in the region. In this direction, SWAT model (Soil and Water Assessment Tool) was used to assess the water availability related with agricultural management in the watersheds of the tributary rivers Cega, Eresma and Adaja of Duero’s River in Spain both in the current and future climate change scenarios. To define the HRUs, land use maps from remote-sensing processes were used, extracting the agricultural uses …

A Conceptual Framework For An Agricultural Agent- Based Model With A Two-Level Social Component: Modeling Farmer Groups, Tatjana Kuznecova, Alexey A. Voinov

International Congress on Environmental Modelling and Software

In the last decade, collective actions within smallholder groups and cooperatives have been promoted by various development programs and projects. However, to develop appropriate programs and policies aimed at supporting cooperation among farmers, an approach may be required able to reflect the dynamics of an agricultural system resulting from decision-making and interactions between elements at different levels and scales.

In this study, we are focusing on the groups of smallholders organizing for collective crop production and/or marketing. Our aim is to provide an approach and a tool to gain a deeper insight in how cooperative groups emerge and perform under …

Design And Implementation Of Integrated Surveillance And Modelling Systems For Climate- Sensitive Diseases, Michael C. Wimberly, Justin Davis, Geoffrey M. Henebry, Michael B. Hildreth, Yi Liu, Christopher L. Merkord

International Congress on Environmental Modelling and Software

Climatic variations can have a multitude of impacts on human health, ranging from the direct impacts of extreme heat events to indirect effects on the vectors and hosts that transmit a multitude of infectious diseases. Infectious disease surveillance has traditionally focused on monitoring human cases, and in some instances tracking population sizes and infection rates of arthropod vectors and zoonotic hosts. For climate-sensitive diseases, there is potential to strengthen surveillance and obtain early indicators of future outbreaks by monitoring environmental risk factors using broad-scale sensor networks that include earth-observing satellites as well as ground stations. We highlight the opportunities and …

Simulating Structural Change In Agriculture: Modelling Farming Households And Farm Succession, Christian Troost, Thomas Berger

International Congress on Environmental Modelling and Software

The majority of European farms are family farms. Farm succession, i.e. passing over the responsibility from farm owner and manager to their heir, is an important element of structural change in agriculture. We present a model implementation capturing farming household evolution in an agent- based model and explore the consequences of farm household composition and farm succession on agricultural production, investment and participation in agri-environmental policy schemes.

A Dynamic Water Supply Portfolio Optimisation Approach, Michael G. Porter, Oz Sahin

International Congress on Environmental Modelling and Software

This paper examines the future water supply situation in Adelaide, a relatively dry city in South Australia, in the driest populated continent on earth. Using the Systems Approach, we analyse a diversified strategy with a new portfolio mix of core bulk water: (i) rainfall independent desalinated water from the ocean and (ii) rainfall dependent water from catchments including the Mount Lofty Ranges (MLR) and water piped from the Murray‐Darling Basin (MDB) including via the Mannum‐Adelaide Pipeline. Our focus is on the quantity, indicative costs and risks of water supply, and associated augmentation choices and trade‐offs, over the next century to …

Modelling Urban Transition: A Case Of Rainwater Harvesting, Adam C. Castonguay, Christian Urich, Md Sayed Iftekhar, Ana Deletic

International Congress on Environmental Modelling and Software

Cities are increasingly exposed to extreme climate events such as floods and droughts. Land use change is also expected to reduce the availability of green spaces and intensify extreme heat events. Given these pressures on the quality of life of urban dwellers, there is a great need to improve the integrated management of water to enable sustainable development of rapidly growing cities and improve human well-being. A promising way to make urban communities more liveable is to invest in green water technologies, that is, decentralised and low-energy water supply, wastewater and stormwater solutions, to foster the transition to more sustainable …

An Optimization Approach To Define Effective Air Quality Policies At Urban Scale, Helder Relvas, Ana Isabel Miranda, Joana Ferreira, Alexandra Monteiro, Enrico Turrini, Claudio Carnevale, Marialuisa Volta

International Congress on Environmental Modelling and Software

The use of modeling to support environmental authorities to plan air quality control policies is now quite widespread in Europe. At the sub-national level, the most common approach is based on a scenario analysis which uses Chemical Transport Models (CTM) to assess the impact of emission reductions on air pollution concentrations. In this work, a multi-objective approach based on RIAT+ (Regional Integrated Assessment Tool) is used to cost-efficiently define air quality improvement policies. Internal costs (due to the implementation of emission reduction measures) and external benefit gains (due to the reduction of population exposure to air pollution levels) are worked …

A Better Way To Build Plant Models, Dean Holzworth, Hamish Brown, Neil Huth

International Congress on Environmental Modelling and Software

The plant modelling framework (PMF) in the next generation of APSIM enables plant models to be constructed in a novel, more reliable and robust manner. It provides a library of small processes that can be aggregated into bigger processes which in turn can be combined into larger constructs, ultimately forming a plant model. The user interface supports a workflow that allows the model builder to collate and store experimental data, construct the model (by process aggregation), create and run simulations of the experimental data and graphically view the performance of the model. The model builder can then iteratively modify the …

Towards Standard Variable Names For Environmental Chemistry: Semantic Mediation And Extensions To The Csdms Standard Names, Scott Dale Peckham

International Congress on Environmental Modelling and Software

When a model needs to obtain the values of its input variables from another model or from a data file, it is necessary to reliably match the internal vocabularies of the coupled resources (e.g. models or data sets). In addition, spatial regridding, time interpolation and unit conversion may be required. In order to automate this semantic matching and variable exchange process in a model coupling framework, the internal vocabularies of the resources to be coupled must be mapped to a controlled vocabulary in a hub-and-spoke manner. The CSDMS Standard Names provide a domain-independent set of conventions and rules for constructing …

How Modellers Frame Uncertainty In Scientific Publications: Review And Reflections, Joseph H.A. Guillaume, Casey Helgeson, Sondoss Elsawah, Anthony J. Jakeman, Matti Kummu

International Congress on Environmental Modelling and Software

Uncertainty is recognised as an essential issue in environmental modelling. As modellers, we notably use a variety of tools and techniques within an analysis, for example related to uncertainty quantification and model validation. We also address uncertainty by how we present results. For example, experienced modellers are careful to distinguish robust conclusions from those that need further work, and the precision of quantitative results is tailored to their accuracy. In doing so, the modeller frames how uncertainty should be interpreted by their audience. This is an area which extends beyond modelling to fields such as philosophy of science, semantics, discourse …

Modelling Combinations Of Economic Instruments To Eliminate Depletion In The Alto Guadalentín Aquifer (Se Spain), David Martínez-Granados, Javier Calatrava

International Congress on Environmental Modelling and Software

This paper analyses the cost-effectiveness of combining several policy instruments to address the problem of non-renewable pumping in the Alto Guadalentín aquifer in Southeast Spain, one of the most extreme cases of aquifer depletion in Europe. Their economic impact is assessed using a partial equilibrium non-linear mathematical programming model that maximises the farm net margin resulting from the use of the available water resources for irrigation in the area. Our results show that all the alternatives have significant economic impacts, although the future availability of desalinised resources would notably mitigate them, as farmers can substitute groundwater with desalinised water. …

In-Field Fuel Use And Load States Of Agricultural Field Machinery, Santosh Pitla, Joe D. Luck, Jared Werner, Nannan Lin, Scott A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The ability to define in-field tractor load states offers the potential to better specify and characterize fuel consumption rate for various field operations. For the same field operation, the tractor experiences diverse load demands and corresponding fuel use rates as it maneuvers through straight passes, turns, suspended operation for adjustments, repair and maintenance, and biomass or other material transfer operations. It is challenging to determine the actual fuel rate and load states of agricultural machinery using force prediction models, and hence, some form of in-field data acquisition capability is required. Controller Area Networks (CAN) available on the current model tractors …

Integration Of Models For Low Carbon Economy, Getachew F. Belete, Alexey Voinov

International Congress on Environmental Modelling and Software

Designing the transition to low carbon economy is a very complex task that touches upon a wide variety of climate-energy-economic systems. We need to explore the various possible climate mitigation scenarios at different temporal and spatial scales. However, due to the diversity of the involved disciplines it is difficult to find one complete and unified modeling approach that works equally well in all those different domains. As a result we have to select 'appropriate' models, which represent only specific aspects of the scenarios and assemble them 'coherently'. In this research we have identified some challenges in integrating multidisciplinary models; and …

A Decision Support System Approach For Identifying Poliutant Source For Optimization Of Beneficial Management Practices Scenario Modelling In Lake Winnipeg Watersheds, Isaac Wong, Luis Leon, Jason Vanrobaeys, Craig Mccrimmon, Phil Fong

International Congress on Environmental Modelling and Software

The Soil and Water Assessment Tool (SWAT) results can be used to source trace loading "hotspots• for optimally locating beneficial management practices (BMP). It is possible to trace upstream and compute the relative contribution of each sub-basin to a point of interest, accounting for in-stream processes, reservoirs and point sources. A decision support system (DSS) framework was developed to run SWAT, perform the otherwise tedious process of source tracing "hotspots" and to optimize BMP locations. The "Crop to Hay- land use change BMP scenario was applied in an attempt to reduce annual loadings of total phosphorus (TP) for three Lake …

Agroecosystem-Watershed (Ages-W) Model Delineation And Scaling, Timothy R. Green, Robert H. Erskine, James C. Ascough Ii, Bruce Vandenberg, Björn Pfennig, Holm Kipka, Olaf David, Micheal L. Coleman

International Congress on Environmental Modelling and Software

Water movement and storage within an agricultural watershed can be simulated at different spatial resolutions of land areas or hydrological response units (HRUs). Interactions between HRUs in space and time vary with the HRU sizes, such that natural scaling relationships are confounded with the simulation scales. Scaling concepts can be tested using the AgroEcoSystem­ Watershed (AgES-W) model with different resolutions of HRUs. Here, we delineated a 56-ha agricultural watershed in northern Colorado, USA farmed primarily under a wheat-fallow rotation. Factors used to distinguish HRUs included topography (surface flow paths), land use (crop strips and native grass), and mapped soil units …

Global Sensitivity Analysis Of Key Parameters In A Process-Based Sugarcane Growth Model - A Bayesian Approach, Justin Sexton, Yvette Everingham

International Congress on Environmental Modelling and Software

While several statistical methods are available to analyse model sensitivity, their application to complex process-based models is often impractical due to the large number of simulation runs required. A Bayesian approach to global sensitivity analysis can greatly reduce the number of simulation runs required by building an emulator of the model which is less computationally demanding. A Gaussian Emulation Machine (GEM) was used to efficiently assess the sensitivity of key agronomic outputs from the APSIM-Sugar crop model to influential input parameters. The sensitivity of simulated biomass and sucrose at harvest was assessed on 14 parameters representing varietal differences and growth …

Dynamic Feedback Between Land Use And Hydrology For Ecosystem Services Assessment, Seleshi Getahun Yalew, Tobias Pilz, Christian Schweitzer, Stefan Liersch, Johannes Van Der Kwast, Marloes L. Mul, Ann Van Griensven, Pieter Van Der Zaag

International Congress on Environmental Modelling and Software

Ecosystem services assessment requires an integrated approach, as it is influenced by elements such as climate, hydrology and socio-economics, which in turn influence each other. However, there are few studies that integrate these elements in order to assess ecosystem services. Absence of integrated approach to modelling hydrological and land-use changes, for instance, often oversights the dynamic feedback between the two processes. Dynamic changes in land-use should be fed into hydrological models and vice-versa at each time-step for a more realistic representation. In this study, this approach is demonstrated with a case study of the uThukela catchment, South Africa. There is …

Ontology Mapping In Semantic Time Series Processing In Climate Change Prediction, Bojan Božić, Jan Peters-Anders, Gerald Schimak

International Congress on Environmental Modelling and Software

In today's time series processing there is more and more a need for addressing diverse user groups interested in a specific domain with appropriate user tailored time series data. The complexity of time series (e.g. involved data from different data sources and/or domains, visualization and representation, etc.) is growing rapidly. As a consequence, it means that users need to find a path through the jungle of time series data. After we have presented our concepts for semantic time series filtering and enrichment of time series with meta-information and annotations (Božić et al., 2012), we are now going to present a …

Metadata Extraction Using Semantic And Natural Language Processing Techniques, Rob Knapen, Thomas Hüsing, Klaus Jacob, Yke Van Randen, Stefan Reis, Onno Roosenschoon, Sander Janssen

International Congress on Environmental Modelling and Software

The World Wide Web and related technologies are playing an increasing role in the field of Integrated Environmental Modelling (IEM). Model integration software frameworks are more and more becoming web-enabled. The technologies and standards of the Web are used to access and run simulation models remotely (known as the Web of models) and are considered for enabling interoperability across model integration frameworks. Furthermore there is a growing number of local and global initiatives to provide open access to environmental data (Web of data) that can potentially be used as input for the scientific models. The availability of descriptive information of …

Improved Implicit Stochastic Optimization Technique For Multireservoir Water Systems Under Drought Conditions, Andrea Sulis

International Congress on Environmental Modelling and Software

Drought is a creeping phenomenon, making its onset and end difficult to determine. Damages from droughts can exceed those resulting from any other natural hazard, although it is difficult to assign a monetary value to them. In the Mediterranean area a severe drought period occurred over the years 2000-2002 and economic losses from that drought exceeded 250 million euros in Sardinia (Italy) (source: ENAS Regional Water Authority). Currently, technological developments and environmental modelling tools are improving our ability to more effectively manage water supply systems. Models can provide decision makers with better and more timely data and information. In this …

Challenges/Advances In Distributed Watershed Modeling: A Review And Application Of The Agroecosystem-Watershed (Ages-W) Model, James C. Ascough Ii, Timothy R. Green, Olaf David, Holm Kipka, Gregory S. Mcmaster, Manfred Fink, Peter Krause, Sven Kralisch

International Congress on Environmental Modelling and Software

Progress in the understanding of physical, chemical, and biological processes influencing water quality, coupled with advances in the collection and analysis of hydrologic data, provide opportunities for significant innovations in the manner and level with which watershed-scale processes may be quantified and modeled. This paper first provides a brief review of current challenges and advances in distributed watershed modeling including quantifying and coping with the uncertainty, data availability, influence of data resolution and scaling issues, and the use of environmental modeling frameworks that help maintain model modularity, reusability, and interoperability (or compatibility). Important findings and observed trends from this work …

Linking A Modified Epic-Based Plant Growth Model (Upgm) With A Component-Based Watershed Model (Ages-W), Gregory S. Mcmaster, James C. Ascough Ii, Debora A. Edmunds, Olaf David, Larry E. Wagner, Fred A. Fox, Robert H. Erskine, Holm Kipka, Timothy R. Green

International Congress on Environmental Modelling and Software

Agricultural models and decision support systems (DSS) for assessing water use and management are increasingly being applied to diverse geographic regions at different scales. This requires models that can simulate different crops, however, very few plant growth models are available that "easily" can simulate the growth of many common and alternative crops. One option available is a suite of plant growth models based on the original plant growth model used in EPIC (Erosion Productivity Index Calculator). Various versions of the original EPIC plant growth model have been used in other agroecosystem models such as the Wind Erosion Prediction System (WEPS), …

Assessing The Transition To A Low-Carbon Economy Using Actor-Based System-Dynamic Models, Dmitry V. Kovalevsky, Klaus Hasselmann

International Congress on Environmental Modelling and Software

For a comprehensive analysis of climate mitigation policies, Integrated Assessment models (IAMs) of the coupled climate-socioeconomic system are needed. However, while there is general agreement on the physics of the climate system, the dynamics of the socioeconomic system is still the subject of considerable controversy. This has become particularly apparent since the recent global financial crisis. To explore the dynamics of the socio-economic system, a family of socio-economic models is proposed that incorporates the various alternative assumptions regarding the behaviour of the different economic actors that govern the evolution of the socio-economic system. The model family needs to be developed …

Enhancing The Policy Relevance Of Scenarios Through A Dynamic Analytical Approach, Céline Guivarch, Vanessa Schweizer, Julia Rozenberg

International Congress on Environmental Modelling and Software

We present a new dynamic analytical approach for studying scenarios produced by an integrated assessment {IA) model. Our approach involves the analysis of a large number of scenarios, which can better address three principal shortcomings of how uncertainty is traditionally handled in IA scenario studies. The shortcomings are all a result of the prevailing practice of investigating a small number of scenarios and include (1) the ad hoc nature of exploring vast socioeconomic uncertainties with only a small number of scenarios; (2) the conventional representation of alternative scenario typologies as "parallel universes• or "diverging universes•, which provide little insight on …

Development Of A Decision Support Tool To Allocate Irrigation Water On Competitive Basis: Application To Kathiraveli Village, Sri Lanka, Tom Le Cerf, Muhammed A. Bhuiyan

International Congress on Environmental Modelling and Software

This paper focuses specifically on the irrigation field and water supply tanks for ways to improve efficiency of water use and increase the resilience to climatic variability. The purpose of this paper is to develop an excel-based water balance model that will allow the maximum cropping area be planted in the upcoming agricultural season. The model consists of three modules: a crop water requirement calculator that allows the water requirements of specific crops to be compared, a water tank balance model, and a model which simulates the storage in the permanent wetland attached to the irrigation tank. The hydrological computation …

Modelling Biofilm Based Technologies With Activated Sludge Unit Processes: A Short Cut To Performance Simulation?, Noella Jones, Maebh Grace, Eoghan Clifford

International Congress on Environmental Modelling and Software

Biofilm-based passive aeration systems (PAS) have attracted recent attention as alternative, energy efficient and low maintenance technologies in the wastewater sector. However the modelling of biofilm-based PAS offers unique challenges for modellers, particularly where new technologies are not easily simulated using existing commercial modelling software. However, if the modeller is concerned only with simulating "macro" plant performance (e.g. key effluent concentrations and cycle analysis) it may be possible to efficiently model these technologies using "surrogate" unit process systems (e.g. using an activated sludge process to model a biofilm process). The pumped flow biofilm reactor (PFBR); a batch biofilm technology, is …

A Best-Worst Scaling Model Of Climate Change Abatement By Australian Farmers, Marit E. Kragt, Nikki Dumbrell, Fiona Gibson

International Congress on Environmental Modelling and Software

Storing carbon from the atmosphere in terrestrial sinks has been proposed as an important way to mitigate climate change and is a major focus in Australia's climate change policies. Mitigation by changing agricultural practices is seen as a promising way to achieve significant reductions in C02 concentrations. Several policies therefore aim to stimulate farmers to adopt so-called 'carbon farming' practices. However, there is little information about farmers' ability and willingness to adopt carbon farming. We present a best-worst scaling model to analyse farmers' decisions about adopting climate change mitigating practices. Best-worst scaling data was collected through a survey amongst mixed …