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An Overview Of The Nevada Climate Change Portal, Sergiu Dascalu, Frederick C. Harris Jr., Michael Mcmahon Jr., Eric Fritzinger, Scotty Strachan, Richard Kelley Jun 2014

An Overview Of The Nevada Climate Change Portal, Sergiu Dascalu, Frederick C. Harris Jr., Michael Mcmahon Jr., Eric Fritzinger, Scotty Strachan, Richard Kelley

International Congress on Environmental Modelling and Software

Created with support from an NSF EPSCoR Research Infrastructure Improvement (RII) grant completed in 2013, the Nevada Climate Change Portal (NCCP) serves as a cyberinfrastructure hub that provides data and computing resources for scientists studying the effects of climate change in Nevada. In particular, the NCCP has been designed for data acquisition, storage, access, and processing in support of long-term assessment of climate variability in Nevada and its impact on the state’s ecological and hydrological systems. The NCCP also serves as a central repository of climate-related information for other stakeholders, including educators, students, and the public. In this paper we …


Web Applications That Share Level-12 Huc Data And Models Of The Conus, Lorne Leonard, Christopher J. Duffy Jun 2014

Web Applications That Share Level-12 Huc Data And Models Of The Conus, Lorne Leonard, Christopher J. Duffy

International Congress on Environmental Modelling and Software

HydroTerre web applications and services provide the Essential Terrestrial Variable (ETV) datasets to create common hydrological models anywhere in the continental United States (CONUS). This service allows web users to download data for their own purposes in their own computing environment. The datasets are provided using standard Geographic Information System formats and the data transformation is dependent on the users own needs, goals, and computing environment. In this article, we demonstrate three web applications and web services that share data and models with users via web interfaces, which automate the data-transformations for United States Geological Survey level-12 Hydrological Unit Codes …


Global Sensitivity Analysis In Environmental Water Quality Modelling: Where Do We Stand?, Giorgio Mannina, Alida Cosenza, Manandraitsiory Randrianantoandro, Franҫois Anctil, Marc B. Neumann, Peter A. Vanrolleghem Jun 2014

Global Sensitivity Analysis In Environmental Water Quality Modelling: Where Do We Stand?, Giorgio Mannina, Alida Cosenza, Manandraitsiory Randrianantoandro, Franҫois Anctil, Marc B. Neumann, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Global sensitivity analysis (GSA) is a valuable tool to support the use of mathematical models for environmental systems. During the last years the water quality modelling field has embraced the use of GSA. Environmental water quality modellers have tried to transfer the knowledge and experience acquired in other disciplines. The main objective of this paper is to provide an informed problem statement of the issues surrounding GSA applications in the environmental water quality modelling field. Specifically, this paper aims at identifying, for each GSA method, the potential use, the critical issues to be solved and the limits identified in a …


A Simple And Effective Approach To Global Sensitivity Analysis Based On Conditional Output Distributions, Francesca Pianosi, Thorsten Wagener Jun 2014

A Simple And Effective Approach To Global Sensitivity Analysis Based On Conditional Output Distributions, Francesca Pianosi, Thorsten Wagener

International Congress on Environmental Modelling and Software

Predictions of environmental models are affected by unavoidable and potentially large uncertainty. When models are applied to understand dominant controls of the system under study, uncertainties will reduce our ability to choose between competing hypotheses. When they are used to support decision-making, uncertainties will reduce our ability to discriminate between different management options and undermine the defensibility of the decision-making process. Global Sensitivity Analysis (GSA) provides quantitative information about the contribution to the uncertainty in the model output arising from different input factors like, for instance, model parameters, boundary conditions or forcing data. GSA thus provides insights into the model …


A Model Component For Simulating The Seasonal Cycle Of Heterotrophic Respiration, G. A. Alexandrov Jun 2014

A Model Component For Simulating The Seasonal Cycle Of Heterotrophic Respiration, G. A. Alexandrov

International Congress on Environmental Modelling and Software

Heterotrophic respiration, an important item in ecosystem carbon balance, is the process which is addressed in the global carbon cycle models and Earth system models. The seasonal cycle of the het- erotrophic respiration is determined by seasonal changes in climatic conditions and in the storage of litter (i.e., in the amount of organic substrate available as a food source for organisms composing the heterotrophic community). The model component presented in this paper is focussing at effects produced by seasonal depletion in litter storage. The seasonal changes in litter storage are modelled by ordinary differential equa- tions, which are solved analytically …


Model Structure Sensitivity Of River Water Quality Models For Urban Drainage Impact Assessment, Frank Blumensaat, Jana Seydel, Peter Krebs, Peter A. Vanrolleghem Jun 2014

Model Structure Sensitivity Of River Water Quality Models For Urban Drainage Impact Assessment, Frank Blumensaat, Jana Seydel, Peter Krebs, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Numerical modeling of physicochemical conditions in rivers influenced by urban drainage and other pressures is increasingly used as supportive method for an integrative environmental impact assessment. In various European countries, protocols for water quality based impact assessment (WQA protocols) are in use, of which many propse the use of water quality models. Despite the increased effort to study uncertainty issues in river water quality modeling in recent years, identifying and differentiating model structure uncertainty remains a challenging task. This study elaborates upon a key conflict in model development: the need to simplify and to still ensure structural adequacy to obtain …


Activated Sludge With Total Solids Retention: Modified-Asm1 Modelling And Simulation, Cheikh Fall, Anabel Jimenez-Zarate, Ericka Millan-Lagunas, Yves Comeau Jun 2014

Activated Sludge With Total Solids Retention: Modified-Asm1 Modelling And Simulation, Cheikh Fall, Anabel Jimenez-Zarate, Ericka Millan-Lagunas, Yves Comeau

International Congress on Environmental Modelling and Software

There are many new strategies put forward for minimizing excess sludge generation in biological wastewater treatment. Some of them were developed within the context of dynamic activated sludge modelling (ASM). A number of means can be used to eliminate the traditional waste activated sludge flow and the build-up of inert solids in the aeration tanks. This includes the use of fine screens to remove the inert particulate organic fraction (XI), hydrocyclones to lower the inorganic suspended solids (ISS), and different kinds of on-line digesters to further biodegrade the endogenous residues (XP), via the return activated sludge …


Supporting Environmental Modelling With Taverna Workflows, Web Services And Desktop Grid Technology, Ferenc Horváth, Péter Ittzés, Dóra Ittzés, Zoltán Barcza, Laura Dobor, Dóra Hidy, Attila Marosi, Alex Hardisty Jun 2014

Supporting Environmental Modelling With Taverna Workflows, Web Services And Desktop Grid Technology, Ferenc Horváth, Péter Ittzés, Dóra Ittzés, Zoltán Barcza, Laura Dobor, Dóra Hidy, Attila Marosi, Alex Hardisty

International Congress on Environmental Modelling and Software

Ecosystem functioning, climate change, and multiple interactions among biogeochemical cycles, climate system, site conditions and land use options are leading-edge topics in recent environmental modelling. Terrestrial ecosystem models are widely used to support carbon sequestration and ecosystem studies under various ecological circumstances. Our team uses the Biome-BGC model (Numerical Terradynamic Simulation Group, University of Montana), and develops an improved model version of it, called Biome-BGC MuSo. Both the original and the improved model estimate the ecosystem scale storage and fluxes of energy, carbon, nitrogen and water, controlled by various physical and biological processes on a daily time-scale. Web services were …


Uncertainty Transfer In Modeling Layers: From Gcm To Downscaling To Hydrologic Surface-Groundwater Modeling, John F. Mejia, Richard G. Niswonger, Justin Huntington Jun 2014

Uncertainty Transfer In Modeling Layers: From Gcm To Downscaling To Hydrologic Surface-Groundwater Modeling, John F. Mejia, Richard G. Niswonger, Justin Huntington

International Congress on Environmental Modelling and Software

In this presentation we show how model uncertainty is transferred from GCMs to hydrologic model results for different downscaling strategies. We use a USGS Groundwater and Surface-water FLOW (GSFLOW) model applied to three small catchments in the northeastern Lake Tahoe basin. A framework is developed for assessing the benefits and difficulties associated with using historical and future climate projections from CMIP3 and CMIP5 datasets for hydrologic investigations. Here we downscale 10 km gridded GCM climate data to a 60m grid using daily values from climate stations and PRISM average monthly climate. Hydrologic model results show that an ensemble/probabilistic station- based …


Modelling Spatial Relationships Between Ecosystem Services And Agricultural Production In An Agent- Based Model, Changxing Dong, Mark Brady, Yann Clough, Ullrika Sahlin, Christoph Sahrbacher, Martin Stjernman Jun 2014

Modelling Spatial Relationships Between Ecosystem Services And Agricultural Production In An Agent- Based Model, Changxing Dong, Mark Brady, Yann Clough, Ullrika Sahlin, Christoph Sahrbacher, Martin Stjernman

International Congress on Environmental Modelling and Software

The collective impacts of farmers’ land management decisions on above ground ecosystem services (ES) and their implications for agriculture are poorly understood. Managing habitat to provide ES is costly but at the same time it can support higher yields through, e.g., pollination or natural pest control. Due to the mobility of ES-providers (bees, natural enemies) farmers providing habitat might also benefit their neighbours, creating interdependencies among their decisions. Interdependencies among farmers’ land-use decisions and the flow of ES in space can be considered by integrating agent-based modelling and evidence-based ES models. Such integration requires a trade-off between the land-use details …


Leveraging Quality Assurance And Quality Control Processes To Deliver Provenance As A First-Order Scientific Output In Large-Scale Environmental Assessments, William Francis, Nicholas J. Car, Rebecca K. Schmidt, Simon Gallant Jun 2014

Leveraging Quality Assurance And Quality Control Processes To Deliver Provenance As A First-Order Scientific Output In Large-Scale Environmental Assessments, William Francis, Nicholas J. Car, Rebecca K. Schmidt, Simon Gallant

International Congress on Environmental Modelling and Software

In large-scale environmental assessments, such as the Australian Government Bioregional Assessment Programme, the science is integrated when products (scientific reports) are assembled. Product assembly involves synthesising material written by multiple authors from multiple disciplines and producing standard tables, maps and charts. High-quality products require that quality assurance and quality control (QA/QC) procedures are built into the scientific and publication processes.

Further, funders and stakeholders are increasingly demanding that scientists provide sufficient infor- mation to explain and justify the evidence provided, even to the extent that an independent group can repeat the science. Recording an effective lineage of processes and data …


Testing Tales: Selection And Evaluation Of A Framework For Interoperable Freshwater Modelling, Alexander Elliot, Gabriella Turek, Valerie Snow, Daniel Rutledge, Alistair Ritchie, Alexander Herzig Jun 2014

Testing Tales: Selection And Evaluation Of A Framework For Interoperable Freshwater Modelling, Alexander Elliot, Gabriella Turek, Valerie Snow, Daniel Rutledge, Alistair Ritchie, Alexander Herzig

International Congress on Environmental Modelling and Software

Recent freshwater policy initiatives in New Zealand have highlighted the need for integrated and interoperable freshwater models and data sources. In response, we evaluated a range of software frameworks for interoperable freshwater modelling. A workshop on user needs identified a spectrum of framework users, ranging from ‘indirect users’ such as policy makers, to ‘developers’ such as software engineers concerned with developing and implementing frameworks. To address calls for clearer information on available models and data sources, we developed databases of models and data sources along with an interactive tool to query the database and illustrate potential data-model and model-model couplings. …


Are The Driving Forces Of Hydrological Models Really Driving The Model Output?, Jiri Nossent, Willy Bauwens, Fernando Pereira, Toon Verwaest, Frank Mostaert Jun 2014

Are The Driving Forces Of Hydrological Models Really Driving The Model Output?, Jiri Nossent, Willy Bauwens, Fernando Pereira, Toon Verwaest, Frank Mostaert

International Congress on Environmental Modelling and Software

Rainfall is very often considered as the driving force of hydrological models. If the rainfall changes, the model output (i.e. flow) is also expected to change. In principal, as long as the values of the model parameters are fixed, rainfall will indeed determine the model output. Yet, uncertainties on the input, the model(parameters) and the output lead to variations of the actual values and can disrupt this rigid hypothesis. Hence, the question could be raised if it would be possible to maintain exactly the same initial model output when the model input changes, by varying the model parameter values? Or, …


Accounting For Groups Of Animals In Qmra Of Recreational Waters, Richard W. Muirhead, Vanessa M. Cave Jun 2014

Accounting For Groups Of Animals In Qmra Of Recreational Waters, Richard W. Muirhead, Vanessa M. Cave

International Congress on Environmental Modelling and Software

The development of QMRA for recreational waters often involves assessing the inputs from multiple sources, including human sewage, agricultural sources and wild animals. The concentrations of microorganisms in faeces from individual animals are highly variable leading to a broad spectrum of risk. When modelling the load of faecal microbes from a group of animals, based on data from individuals, the group distribution must be correctly accounted for. A further complication to QMRA is that pathogen concentrations in faeces have a high proportion of non-detects making them difficult to model using standard mathematical distributions. Moreover, when only limited concentration data are …


An Integrative Modeling Framework To Evaluate Wheat Production Systems: Fusarium Head Blight, Willingthon Pavan, José Maurício Cunha Fernandes, Alexandre Lazzaretti, Josué Toebe, Jorge Luis Bavaresco, Alex C. Ruane, Rodrigo Yoiti Tsukahara Jun 2014

An Integrative Modeling Framework To Evaluate Wheat Production Systems: Fusarium Head Blight, Willingthon Pavan, José Maurício Cunha Fernandes, Alexandre Lazzaretti, Josué Toebe, Jorge Luis Bavaresco, Alex C. Ruane, Rodrigo Yoiti Tsukahara

International Congress on Environmental Modelling and Software

This paper describes a practical, integrated, web-based and user friendly analysis tool for crop model users that provides quality control of input data, tracks user selections in model parameterization, and enables visual analysis of model outcomes using a single graphical user interface. This allows the user to undertake numerous steps in crop modeling and analysis in a seamless and integrated environment. The analysis and visualization components of the system were enabled utilizing R (pl/r) and the robustness of the underlying data structures and coupling point between crop and disease models were achieved through use of PostgreSQL database management system. The …


Estimating The Benefits Of Early Warning Systems In Reducing Urban Flood Risk To People: A Spatially Explicit Bayesian Model., Stefano Balbi, Ferdinando Villa, Vahid Mojthaed, Carlo Giupponi Jun 2014

Estimating The Benefits Of Early Warning Systems In Reducing Urban Flood Risk To People: A Spatially Explicit Bayesian Model., Stefano Balbi, Ferdinando Villa, Vahid Mojthaed, Carlo Giupponi

International Congress on Environmental Modelling and Software

Flood risk assessment usually focuses on damages to material objects (indirect tangible costs) and downplays the broader socio-economic aspects of flood-prone systems. Such aspects are crucial for an accurate assessment of risk to human receptors and of the benefits of non-structural measures. For example, an early warning system (EWS) that reduces the amount of direct tangible costs only partially could: (i) save lives (direct intangible costs); (ii) help avoid long-lasting trauma (indirect intangible costs); (iii) prevent post-disaster evacuation costs (indirect tangible costs). We present a methodology to assess flood risk to people, which integrates people's vulnerability and ability to cushion …


Applications Of Quantitative Microbial Risk Assessment (Qmra) To Regulatory Decision Making, Adam W. Olivieri, Edmund Y. Seto, Richard E. Danielson, Jeffrey A. Soller, Robert C. Cooper Jun 2014

Applications Of Quantitative Microbial Risk Assessment (Qmra) To Regulatory Decision Making, Adam W. Olivieri, Edmund Y. Seto, Richard E. Danielson, Jeffrey A. Soller, Robert C. Cooper

International Congress on Environmental Modelling and Software

Intelligent risk-based decision-making requires a clear and transparent framework, and as part of that framework, includes a tractable analysis and balancing of various qualities of information from numerous sources. The purpose of this paper is to provide a number of examples on the application of QMRA, and how the information was utilized to aid and facilitate decision-making as part of the regulatory process for evaluating water recycling and municipal treatment plant discharges.


Quantitative Microbial Risk Assessment Of Freshwater Impacted By Animal Fecal Material, Jeffrey Soller, Timothy Bartrand, Marirosa Molina, Gene Whelan, Mary Schoen, Nicholas Ashbolt Jun 2014

Quantitative Microbial Risk Assessment Of Freshwater Impacted By Animal Fecal Material, Jeffrey Soller, Timothy Bartrand, Marirosa Molina, Gene Whelan, Mary Schoen, Nicholas Ashbolt

International Congress on Environmental Modelling and Software

We evaluated the potential for human illness from a hypothetical recreational exposure to freshwater that was impacted by land-applied, agricultural animal fecal material. The scenario included 1) fresh cattle manure, pig slurry, or chicken litter (fecal material) land-applied, adjacent to a freshwater waterbody at standard agronomic rates (based on nutrient management); 2) fecal materials containing fecal indicator bacteria (FIB) and pathogens of public health concern (reference pathogens) at levels reported in peer-reviewed literature; 3) FIB and reference pathogens mobilized via runoff at rates estimated from our rainfall simulation experiments; 4) primary recreational contact (e.g., swimming) occurring in undiluted runoff at …


Amadeus: A System For Monitoring Water Quality Parameters And Predicting Contaminant Paths, Abdeltawab M. Hendawi, David Hazel, Joel Larson, Yiru Li, Dwaine Trummert, Mohamed Ali, Ankur Teredesai Jun 2014

Amadeus: A System For Monitoring Water Quality Parameters And Predicting Contaminant Paths, Abdeltawab M. Hendawi, David Hazel, Joel Larson, Yiru Li, Dwaine Trummert, Mohamed Ali, Ankur Teredesai

International Congress on Environmental Modelling and Software

Managing the water quality in an urban environment is extremely challenging. While it flows, the water picks up pollutants such as lawn care chemicals, oil, and pet waste bacteria. In fact, topography plays a factor in where water runoff goes. However, there are many other factors, such as urban density, impermeable surface coverage, weather events and tidal patterns which all have the potential to impact not only the final destination of a particular pollutant but also the rate of travel along the route. In this paper, we propose a system, named AMADEUS (Azure Marketplace of Applications for Diverse Environmental Use …


A Spatial Planning Tool For The Evaluation Of The Effect Of Hydrological And Land-Use Changes On Ecosystem Services, Leon Mugwiza, Seleshi Yalew, Johannes Van Der Kwast, Masoom Hamdard, Willem Van Deursen Jun 2014

A Spatial Planning Tool For The Evaluation Of The Effect Of Hydrological And Land-Use Changes On Ecosystem Services, Leon Mugwiza, Seleshi Yalew, Johannes Van Der Kwast, Masoom Hamdard, Willem Van Deursen

International Congress on Environmental Modelling and Software

Many point-based models have been designed to simulate hydrology, gas flux, nutrient dynamics, and/or plant growth processes at a single point on the landscape. However, these environmental processes are known to be spatially variable. Simulations at different spatial locations therefore require adjustment of model input parameters to reflect specific conditions at each location. Increased availability of geospatial data sets, including remote sensing images, land cover maps, digital soil surveys, crop yield maps, and vehicle-based plant or soil maps, can support spatial model parameterization efforts. However, tools are needed for processing geospatial data layers and interfacing the data with the simulation …


Socio-Economic Regional Risk Assessment (Serra) Application To Flood Risk In The Vipacco Basin (North-East Italy), Claudia De Luca, Vahid Mojtahed, Animesh Gain, Stefano Balbi, Michele Ferri, Carlo Giupponi Jun 2014

Socio-Economic Regional Risk Assessment (Serra) Application To Flood Risk In The Vipacco Basin (North-East Italy), Claudia De Luca, Vahid Mojtahed, Animesh Gain, Stefano Balbi, Michele Ferri, Carlo Giupponi

International Congress on Environmental Modelling and Software

According to EEA (European Environmental Agency), flood is the most dangerous natural hazard in Europe in terms of economic losses. The KULTURisk Project (EU FP7) has developed a novel methodology for evaluating the integrated benefits of risk prevention of water related natural hazards: SERRA (i.e. Socio-Economic Regional Risk Assessment). The proposed methodology enhances the traditional flood risk assessment. Several case studies across Europe allowed for the consolidation, validation, and refinement of SERRA. This paper presents the results of its application to assess the benefits derived from the installation of an Early Warning System in Vipacco river basin in Friuli Venezia …


Reproducible Research Within The Datanet Federation Consortium, Reagan W. Moore, Arcot Rajasekar Jun 2014

Reproducible Research Within The Datanet Federation Consortium, Reagan W. Moore, Arcot Rajasekar

International Congress on Environmental Modelling and Software

The DataNet Federation Consortium (DFC) is an NSF funded project that provides cyberinfrastructure for federating data management systems into a collaboration environment. Researchers are able to build a shared collection, apply analysis workflows, and manage the analysis results. The shared collections may span storage resources at multiple institutions, and multiple types of data management systems. The analysis workflows may include staging of files to remote compute platforms, and in-place analysis at the remote data storage location. The workflows can be captured as shareable objects, with automatic capture of input files, input parameters, and output files. A key feature is support …


Use Of Near Real Time Earth Observation Data Infrastructures And Open Source Tools For Water Resources Monitoring And Assessment, Chris M. Mannaerts, Ben H.P. Maathuis, Petra E. Budde Jun 2014

Use Of Near Real Time Earth Observation Data Infrastructures And Open Source Tools For Water Resources Monitoring And Assessment, Chris M. Mannaerts, Ben H.P. Maathuis, Petra E. Budde

International Congress on Environmental Modelling and Software

Since several years, a rapid and ever increasing public use of geo-information data derived from earth observation satellites is noted. The use of Google and Microsoft Virtual Earth engines can be seen as generic examples of this trend. For hydrology, water resources research and professional practice, we also note a growing availability of earth observation (EO) data and products, needed for operational land and water management. Many of these data are public domain and made freely available using low-cost global data dissemination infrastructures like GEONETCast, managed by the spaces agencies EUMETSAT and NOAA amongst others, within the context of the …


Web Service And Plug-In Architecture For Flexibility And Openness Of Environmental Data Sharing Platforms, Stephen Knox, Philipp Meier, Julien Harou Jun 2014

Web Service And Plug-In Architecture For Flexibility And Openness Of Environmental Data Sharing Platforms, Stephen Knox, Philipp Meier, Julien Harou

International Congress on Environmental Modelling and Software

The sharing, comparison and maintenance of computer model input and result data for real-world projects is a challenge. In collaborative research projects, particularly when collaboration occurs between multiple institutions in different locations, the complications are greater still. The co-development of water resource network simulation and optimization models is one field that faces this challenge. There is a need for ways to allow multiple users to build and apply models collaboratively. This paper argues that a web service architecture is an appropriate approach for multi-institution maintenance of resource network models. We describe the design of a prototype system that allows developers …


Hydroshare: Advancing Collaboration Through Hydrologic Data And Model Sharing, David G. Tarboton, Ray Idaszak, Jeffery S. Horsburgh, Jeff Heard, Dan Ames, Jonathan L. Goodall, Larry Band, Venkatesh Merwade, Alva Couch, Jennifer Arrigo, Richard Hooper, David Valentine, David Maidment Jun 2014

Hydroshare: Advancing Collaboration Through Hydrologic Data And Model Sharing, David G. Tarboton, Ray Idaszak, Jeffery S. Horsburgh, Jeff Heard, Dan Ames, Jonathan L. Goodall, Larry Band, Venkatesh Merwade, Alva Couch, Jennifer Arrigo, Richard Hooper, David Valentine, David Maidment

International Congress on Environmental Modelling and Software

HydroShare is an online, collaborative system being developed for open sharing of hydrologic data and models. The goal of HydroShare is to enable hydrology researchers to easily discover and access hydrologic data and models, retrieve them to their desktop for local analysis and perform analyses in a distributed computing environment that may include grid, cloud or high performance computing. Users may also share and publish outcomes (data, results or models) into HydroShare, using the system as a collaboration platform. HydroShare is expanding the data sharing capability of the CUAHSI Hydrologic Information System by broadening the classes of data accommodated. HydroShare …


Slow Or Rapid Collapse? Transients Between Stable States As A Source Of Uncertainty In Predicting Ecosystem Shifts, Derek Karssenberg Jun 2014

Slow Or Rapid Collapse? Transients Between Stable States As A Source Of Uncertainty In Predicting Ecosystem Shifts, Derek Karssenberg

International Congress on Environmental Modelling and Software

In this study I explore the rate of change during the collapse of a vegetation-soil system on a hillslope from a vegetated state to an unvegetated, bare-soil, state. From a distributed, stochastic model coupling hydrology, vegetation, weathering and wash erosion, I derive two differential equations describing the interaction between the vegetation and the soil. Two stable states--vegetated and bare--are identified by means of analytical investigation, and it is shown that the change between these two states is a critical transition as indicated by hysteresis. Surprisingly, transitions between these states can either unfold rapidly, over a few years, or gradually, occurring …


Plug And Play Component Modeling - The Csdms2.0 Approach, James P. Syvitski Jun 2014

Plug And Play Component Modeling - The Csdms2.0 Approach, James P. Syvitski

International Congress on Environmental Modelling and Software

The CSDMS2.0 focus is on developing a software modelling environment that offers the earth and ocean communities products to enable easier penetration into the world of high performance computing, plug-and-play component modelling, and access to vetted open source surface-dynamics models. Protocols and standards define modelling interfaces, standard names, service components, and DOIs labelling.


A Proposed Approach To The Development Of Federated Model Sets, Kenneth M. Bryden Jun 2014

A Proposed Approach To The Development Of Federated Model Sets, Kenneth M. Bryden

International Congress on Environmental Modelling and Software

Integrated modelling is a critical environmental modelling tool that brings together sets of models and data to describe the impacts of various management practices and choices within the environment. Although each model may (or may not) run on separate hardware, typically these model sets are organized together as a large integrated, centralized model. These integrated models share a single conceptual schema and semantic framework. Additionally, information flow and convergence of boundary conditions between the models are generally built on a fixed framework. Although this is a logical approach that has proven to be effective, it has several limitations. The models …


Feedback Versus Uncertainty, Ronald R. P. Van Nooijen, Markus Hrachowitz, Alla G. Kolechkina Jun 2014

Feedback Versus Uncertainty, Ronald R. P. Van Nooijen, Markus Hrachowitz, Alla G. Kolechkina

International Congress on Environmental Modelling and Software

Even without uncertainty about the model structure or parameters, the output of a hydrological model run still contains several sources of uncertainty. These are: measurement errors affecting the input, the transition from continuous time and space to discrete time and space, which causes loss of information about the input, discretization of the model equations resulting in errors due to the discretization scheme and the use of finite precision calculations in model evaluation. Interval analysis can provide upper bounds on the output error due to all of these sources. This paper focuses on tracking uncertainty about input values and the effects …


Apex-Cute: An Auto-Calibration And Uncertainty Analysis Tool For The Apex Model, Xiuying Wang, Haw Yen Jun 2014

Apex-Cute: An Auto-Calibration And Uncertainty Analysis Tool For The Apex Model, Xiuying Wang, Haw Yen

International Congress on Environmental Modelling and Software

The Agricultural Policy Environmental eXtender - auto-Calibration and UncerTainty Estimator (APEX-CUTE) was developed as an open-source tool which enhances the accessibility for APEX users to conduct potentially tedious calibration work on the APEX model. The role of uncertainty analysis should be taken as an independent supporting package to extend the capability in further analytical purposes. This version of APEX-CUTE incorporates relevant functions of uncertainty analysis flexibly. Users have options to include designated uncertainty sources such as input and/or measurement errors during the calibration process. APEX-CUTE is not only the comprehensive package in performing model calibration on APEX, but it can …