Computer Engineering Commons^™

Machine Learning In Surface Ocean Co2 Mapping, Jive Zeng, Nobuko Saigusa, Tsuneo Matsunaga, Tomoko Shirai

International Congress on Environmental Modelling and Software

Carbon dioxide (CO2) is a major greenhouse gas affecting long term global climate change. According to the Global Carbon Budget 2013 (Quéré et al., 2014, Earth Syst. Sci. Data, 6, 235–263), total global carbon emissions increased from 3.9 GtC/yr in 1959 to 10.7 GtC/yr in 2012, of which approximately 43% remained in the atmosphere, 30% went to terrestrial sinks, and 27% to the oceans. A method to estimate the oceanic sink is by calculating the air-sea CO2 exchange rate of CO2. While obtaining accurate distributions of the surface ocean CO2 (SOC) is critical to minimize uncertainty for this method, it …

Trade-Offs Between Carbon Storage, Crop Yield Production And Water Supply At The Global Scale, Sven Lautenbach, Anita D. Bayer, Almut Arneth

International Congress on Environmental Modelling and Software

Through land-use, humans affect natural ecosystem functioning and ecosystem services (ES). The present pattern of land-use types developed over the last millennia in response to a complex interplay of natural-system constraints and socio-economic pressures. However, the current land-use pattern might not be considered optimal in terms of its provision of a variety of ES. At the global scale food security, water availability and carbon storage are three objectives of highest importance. Knowledge about the trade-offs between these objectives is of concern if global pathways for future developments are discussed. To provide information on these trade-offs we evaluate the global configuration …

Multi-Model Custodianship: Needs, Development And Challenges, Mason Marchildon, Thorsten Arnold, Steve Holysh, Rick Gerber

International Congress on Environmental Modelling and Software

In 2000, the province of Ontario, Canada, embarked on a Source Water Protection program with the objective of providing multi-level protection for drinking water supplies. This initiative was instigated by a tragedy in the town of Walkerton where multiple deaths resulted from ingestion of e-coli contaminated groundwater. As part of the Source Water Protection Program, numerous technically- sophisticated regional-scale hydrological models have been developed. As a result, local government agencies (municipal and conservation authority) have found themselves on a new pathway for water resources management that intends to utilize these numerical models as key tools for understanding and managing water …

From Climate Change Awareness To Energy Efficient Behaviour, Leila Niamir, Tatiana Filatova

International Congress on Environmental Modelling and Software

Understanding and predicting how climate will change, and whether and how a transition to low-carbon economies will develop over the next century is of vital importance. Nowadays there is high competition between countries to achieve a low-carbon economy. They are examining different ways e.g. different energy efficient technologies and low-carbon energy sources, however they believe that human choices and behavioural change has a crucial impact, which is many times discussed in the literature as well. In this paper, we aim to discuss challenges related to modelling behavioural changes on the demand side and show effect of the demand side activation …

Managing A Lake Ecosystem Using A Food-Web Model – Lake Kinneret As A Case Study, Eyal Ofir, Gideon Gal, James Shapiro

International Congress on Environmental Modelling and Software

Lake Kinneret is a freshwater lake located in the northern part of Israel. The lake is one of the most important freshwater resources in Israel, and maintaining a stable ecosystem is of prime importance. The ecosystem has, however, changed dramatically during the last 20 years. Following the destabilization that occurred in the lake ecosystem biomanipulation measures such as fish stocking of certain species and removal of another were used in order to restabilize the ecosystem. Most biomanipulation measures did not succeed in achieving their goals. For instance, 10 years of intense fishing efforts to remove the Lavnun fish (A …

Agro-Ecosystem Adaptation To Climate Change – How Does Crop Model Uncertainty Affect The Choice Of Optimum Adaptation Responses?, A. Holzkämper, T. Klein, R. Seppelt, J. Fuhrer

International Congress on Environmental Modelling and Software

Amongst the crop modelling community, it is now widely acknowledged that model uncertainties can have huge implications on the results from climate impact studies. While uncertainties in climate impact assessments are increasingly being considered, studies investigating the implications of model uncertainties on recommendations for adaptation responses are still very rare. To address this gap, this study investigates how crop model uncertainty can affect the selection of suitable adaptation responses. The agroecosystem model CropSyst is applied in connection with an optimization routine to select optimum adaptation options with regard to different adaptation goals (i.e. maximum productivity, minimum erosion, minimum leaching). By …

Hydrological And Biogeochemical Modelling Of Carbon Fluxes In An Arctic River: The Yenisei (North Of Russia), Clément Fabre, José Miguel Sanchez Perez, Nikita Tananaev, Roman Teisserenc, Grégory Espitalier Noël, Sabine Sauvage

International Congress on Environmental Modelling and Software

Permafrost represents one of the biggest organic carbon stocks on Earth. Organic carbon is exported from rivers to oceans by the particulate (POC) and the dissolved (DOC) form. Carbon fluxes represent 22 to 32 teragrams of carbon per year (TgC.yr^-1; 1 Tg = 10¹² g) in the Arctic Ocean. This export is a main concern in this time of global changes. With global warming, the superficial layer in permafrost could unfreeze deeper and exports of old organic carbon (accumulated for thousands of years) would be possible and could disturb recent carbon cycles. Based on some sporadic data, …

Environmental Model Managment Within The Us Environmental Protection Agency, Andrew J. R. Gillespie

International Congress on Environmental Modelling and Software

The United States Environmental Protection Agency (USEPA) is responsible for formulating and implementing environmental rules and regulations under several major US laws aimed at protecting human health and the environment. USEPA’s work strives to be grounded on a strong and rigorous scientific foundation which increasingly relies on models to improve understanding of complex human- environmental systems. USEPA decisions are frequently challenged in courts, so the underlying science needs to meet a high bar in terms of transparency and scientific rigor established through peer review. USEPA currently has no universal framework for managing models over a lifecycle. There is a grassroots …

Behaviour Change And Incentive Modelling For Water Saving: First Results From The Smarth2o Project, J. Novak, M. Melenhorst, I. Micheel, C. Pasini, P. Fraternali, A. E. Rizzoli

International Congress on Environmental Modelling and Software

Stimulating users to save water is a challenge and an opportunity for water demand management. Existing ICT-based systems for behavioural change often do not consider the underlying behavioural determinants in a systematic way. This paper discusses the design of the behavioural change and incentive model for the SmartH2O system, combining smart meter data with consumption visualisation and gamified incentive mechanisms to stimulate water saving. We show how the design of such a system can be related to a holistic behavioural change model and how this systematic mapping can inform the design of an integrated incentive model combining different incentive types …

Comparative Study Between Spatial-Implicit And -Explicit Model: A Case Study Of Vegetation Pattern In Salt Marshes, Man Qi, Alexey Voinov, Tao Sun

International Congress on Environmental Modelling and Software

From the inception of plant ecology as an independent field, much attention has been focused on understanding spatial and temporal changes in vegetation. Spatially explicit models, such as cellular automation (CA), were widely used to explore simple rules that control vegetation patterns in nature. However, compared to implicit model which was derived from statistic survey and was widely applied to uncover practical issues, spatial explicit model still rests on mimicking the complexities of real behaviours and stimulate new insights about them. Comparative analysis between these two model types was rarely explored. In this study, we simulated the vegetation pattern of …

Assessing Input-Output Relations In Environmental Data By Means Of Fuzzy Clustering And Bayesian Inference, L. Bigozzi, E. El Basri, F. Ianniciello, S. Marsili-Libelli, I. Simonetti

International Congress on Environmental Modelling and Software

When dealing with complex environmental datasets, it is also difficult to establish the strength of the input-output relation among variables. Correlation analysis may yield a preliminary indication, but is limited to the linear case. Mutual Information (MI) is a more powerful method which can establish input-output dependence regardless of the nature of their interaction. However, to avoid the heavy computational demand of MI, a simple method is presented based on fuzzy clustering and Bayes’ rule. After a preliminary conditioning phase, the data are grouped by fuzzy clustering and approximated with the value of the most relevant centroid. Then the prior …

Towards An Ontology Of Ecosystem Services For Modeling The Management Of Their Flows To And From Agriculture, Roger Martin-Clouaire

International Congress on Environmental Modelling and Software

The notion of ecosystem service and afferent concepts are gaining importance in the ecology, environment and sustainability-oriented literature. They have been defined differently and rather loosely however. Although convergence toward undisputed definitions is not attained yet, much structuring material has been used and published in scientific or policy-oriented documents. Since different perspectives exist, confusion and inconsistencies predominate across disciplines and agents involved in this relatively new domain. There is clearly a need for a consistent conceptual basis that could provide well-founded semantics and methodological guidelines to be used in the elaboration, evaluation, exploitation and communications of models of complex systems …

Transformative Modelling To Address High-­End Climate Change, J. David Tabara, Varun Mallampalli, Diana Mangalagiu, Marco Grasso, Jill Jäger, Andrea Roventini, Mark Borsuk, Francesco Lamperti, Robert Lempert

International Congress on Environmental Modelling and Software

The growing plausibility of a world trespassing the 2ºC global warming threshold is unveiling the limitations of existing assessment tools to tackle the multiple non-­linearities, irreversibilities, feedbacks, tipping points and uncertainties associated to entering this new situation. A main challenge for transformative modelling is to unveil potentially disruptive strategies and assess distributed solutions capable of addressing high-­end climate change while reconciling economic, climate and sustainability goals.

To this end, using a transformative Agent-­Based Modelling (t-­ABM) approach, we represent and assess the development and implementation of two distinct green growth strategies vis-­à-­vis a business-­as-­usual one. Strategy S1 is a distributed one, …

Multi-Label Classification Methods For Predicting Mixed Land Use Change, Hichem Omrani, Amin Tayyebi, Amir H. Tayyebi, Bryan Pijanowski

International Congress on Environmental Modelling and Software

Current progress on land use highlights the interest of the multi-label concept in predicting land use change. The new concept allows a multi-label class assignment (ML), where a spatial unit may be associated simultaneously with a set of multiple classes. The multi-label concept is different than the commonly used mono-label one (ml: binary or multi-class), in which a spatial unit has only one elementary label at a time. Recently, it has been shown the merit of the ML concept to model mixed land use change. In this paper, we study the multi-label class-assignment by different multi- label classifications models. The …

Randomness Representation In Turbulent Flows With Bed Roughness Elements Using The Spectrum Of The Kolmogorov Complexity, D. T. Mihailović, G. Mimić, P. Gualtieri, I. Arsenić, C. Gualtieri

International Congress on Environmental Modelling and Software

One feature of turbulent flow in relation to randomness is quantified. Experimental data from a turbulent flow collected in a laboratory channel with bed roughness elements of different densities are used. An analysis based on a classical turbulence statistics is performed, using a simple empirical model for estimating the relative sizes of mixing lengths representing the typical scale of an eddy in the corresponding surface layer, to describe the turbulence in terms of irregular or random flow. Instead of such description a quantification of the turbulence flow using measures based on the spectrum of the Kolmogorov complexity (KC) is proposed.

Modelling Socio-Ecological Problems With Delay. Case Study On Environmental Damage, Veronika Novotná, Bedřich Půža, Jiří Hřebíček

International Congress on Environmental Modelling and Software

The paper presents modelling complex socio-ecological problems, where relations among individual quantities vary in time. This includes dynamics of processes in the model, which enables to understand time as a continuous quantity and to describe dynamic processes by a system of differential equations with delay. Implementation of these models in Maple system enables both analytic and numerical solutions and their visualizations. The Maple solution of the specific example of the model with delayed argument is shown, where all input parameters can be interactively changed during the solution process, i.e. delay, interval of the solution, or other parameters which have an …

System Identification And Control Of Rivers, Hasan Arshad Nasir, Erik Weyer

International Congress on Environmental Modelling and Software

Here we present findings from on-going research on how to improve the management and efficiency of river operations using data based modelling and control engineering. The objectives of the river operations include minimisation of flow and water level deviations from their required set- points, on-time water deliveries to irrigators and flood risk mitigation. Due to long time delays in rivers, forecasts of flows in tributaries are required, and control strategies for rivers should be able to accommodate such forecasts. Here we propose to use system identification techniques to obtain models of the rivers which are very simple, but sufficient for …

Identifying Efficient And Robust Water Supply Investments For East England, Evgenii S. Matrosov, Julien J. Harou

International Congress on Environmental Modelling and Software

In response to uncertainties about climate, population, economic and institutional changes, water resource system planners increasingly seek to select both robust and efficient system designs, i.e., those that work best across a broad set of plausible futures. Concretely water utilities must identify which portfolios of investments in new infrastructure, demand management schemes and increased regional connectivity together lead to cost-effective robust systems. System design under uncertainty methods such as Many-Objective Robust Decision Making (MORDM) help decision makers find robust strategies while optimising over many stakeholder performance objectives. Most studies using many-objective search have focused on relatively small systems with interconnected …

Calibrating Swat For Multiple Agro-Ecosystem Services At Field Scale, N. Zarrineh, A. Holzkämper, Karim C. Abbaspour, J. Fuhrer

International Congress on Environmental Modelling and Software

The Soil and Water Assessment Tool (SWAT) is increasingly used to assess potential impacts on multiple ecosystem services. However, insufficient attention is given to crop growth processes in a field setting that are relevant drivers of important agro-ecosystem services such as crop yield, soil organic matter, or nutrient leaching. The aim of this study was to validate the SWAT model performance for multiple outputs related to agro-ecosystem services. In a Swiss case study, SWAT was set up to simulate a long-term field experiment including four soil tillage treatments with detailed records of management (e.g. sowing, harvesting, fertilizing and tillage). Observed …

Hindcasting The Dynamics Of An Eastern Mediterranean Marine Ecosystem Under The Impacts Of Multiple And Cumulative Stressors, X. Corrales, M. Coll, E. Ofir, M. Goren, D. Edelist, J. J. Heymans, G. Gal

International Congress on Environmental Modelling and Software

An important challenge for conserving and managing marine ecosystems is to advance our understanding of how multiple human stressors, environmental factors and marine resources interact and influence each other. The ecosystems of the Israeli Mediterranean coast have undergone significant ecological changes in recent decades caused primarily by the introduction of invasive species through the Suez Canal, intense fishing activities and the effects of climate change. An Ecopath model representing the continental shelf of the Israeli Mediterranean coast was calibrated and fitted to the available time series from early 1990’s to 2010 using the Ecosim temporal dynamic modeling approach. The model …

Co-Building A Simulation Model With Various Stakeholders To Assess The Sustainability Of A Regional Agricultural System: How To Articulate Different Types Of Knowledge To Manage Uncertainty?, Caroline Tardivo, Christophe Le Page, Jean-Marc Barbier, Laure Hossard, Roberto Cittadini, Sylvestre Delmotte

International Congress on Environmental Modelling and Software

To assess the sustainability of agricultural systems at a regional scale with regards to possible changes in land use and cropping systems, designing simulation models to explore scenarios with stakeholders is a relevant approach. It implies coping with uncertainties from different areas, originating at both levels of imperfect data sets and misunderstood dynamics (due to incompleteness of knowledge and unexpected systemic effects). Additionally, dealing with various types of knowledge to co-design the model generates ambiguity from the simultaneous presence of multiple frames of reference about the system to be represented. On top of that, specifying scenarios to be explored with …

Study On The Buoyancy Plume Model Coupling With The Effects Of Temperature, Salinity And Sediment, Shen Zia, Huang Juping, Yan Zhongluan, Li Ran, Feng Jingjie

International Congress on Environmental Modelling and Software

The paper developed a three-dimensional model for buoyancy plume coupling with the comprehensive effects of different temperature, sediment and salinity. The model includes mass continuity equation, momentum equation and energy equation, state equation, Renormalization Group (RNG) κ-ε turbulence transport equation, sediment scour equation, salinity advection equation. The discretization scheme of Finite Difference Method (FDM) is used to solve Reynolds-Averaged Navier-Stokes (RANS) equation, combining the discretization method of the central difference scheme and the upwind scheme. A method called Generalized Minimal Residual Algorithm (GMRES) is used to solve velocity-pressure term of discrete equation. The volume of fluid (VOF) method is adopted …

Spatial And Dynamic Sensitivity Analysis Of A Biophysical Model Of Nitrogen Transfers And Transformations At The Landscape Scale., Jordi Ferrer Saval, Pierre Barbillon, Cyril Benhamou, Patrick Durand, Marie-Luce Taupin, Hervé Monod, Jean-Louis Drouet

International Congress on Environmental Modelling and Software

Modelling complex systems such as agroecosystems often requires the quantification of a large number of input factors. Sensitivity analyses are useful to fix the appropriate spatial and temporal resolution of models and to reduce the number of input factors to be measured or estimated accurately. Comprehensive spatial and dynamic sensitivity analyses were applied to the Nitroscape model, a deterministic spatially distributed model describing nitrogen transfers and transformations in a rural landscape. Simulations were led on a virtual landscape that represented five years of farm management in an intensive rural area of 3 km². Cluster analyses were applied to summarize the …

A Probabilistic Approach For Participatory Evaluation Of Resource Management Systems, Nagesh Kolagani, Palaniappan Ramu, Ravi Gorripati, Alexey Voinov

International Congress on Environmental Modelling and Software

When planning resource management systems in villages, involving stakeholders in planning these systems is known to lead to better results with more success and less conflict. While planning these systems, stakeholders often need to evaluate several alternatives before selecting one which best suits their requirements. A simple multi criteria decision analysis model which they can understand, such as a linear weighted summation model, will help them in evaluating efficiency of each alternative and ranking it. While using such models, a common practice is to obtain weights of each criterion from stakeholders using methods such as analytic hierarchy process. Values of …

Why Does Dynamic Neighbourhood Configuration Matter In Ca-Based Models? An Exploratory Approach For Luxembourg’S Cross-Border Area, H. Omrani, J. P. Antoni, O. Klein

International Congress on Environmental Modelling and Software

Cellular Automata (CA) based modelling is rapidly emerging as a powerful technique to model complex systems in a wide range of applications. The neighbourhood configuration is one of the key components of CA models. Static neighbourhood configuration (SNC) has been used for a long time in various applications. However the efficiency of a CA model is highly influenced by its SNC and cell size. Recently, a few number of researchers working in land change science have proposed a large neighbourhood configuration (e.g., 10×10 Moore neighbourhood instead of the commonly used 3×3 Moore neighbourhood). The large neighbourhood configuration has shown its …

Analyzing Regime Shifts In Agent-Based Models With Equation-Free Analysis, Romina Martin, Spencer Angus Thomas

International Congress on Environmental Modelling and Software

Conventional tools to analyze regime shifts in ecosystems, e.g. stable state and bifurcation analyses, are increasingly adapted to investigate social-ecological systems. The challenge lies in combining the analysis of system dynamics with the analysis of transient dynamics emerging from adaptive and heterogeneous agents. A typical question is, to which extent do micro level interactions contribute to a macro level outcome? We demonstrate the application of a new tool, equation-free analysis, for evaluating the state space from an agent-based model (ABM) on lake restoration. By sidestepping the requirement of an equation describing a systems macroscopic behavior, equation free analysis enables system …

Numerical Simulation Of A New Three-Dimensional Non-Hydrostatic Model, Ling Kang, Shangwen Jiang

International Congress on Environmental Modelling and Software

The hydrostatic pressure assumption has been widely applied in hydrodynamic numerical simulation in rivers and lakes, but it has been found inappropriate in various cases where the vertical acceleration is significant. To this end, this paper proposes a new three-dimensional, non-hydrostatic hydrodynamic model. Based on Navier-Stokes equations with the σ-coordinate transformation, rectangular grid is adopted as the approximation of the study region. For numerical solution, the process includes two steps, the estimated step and the modified step. The FDM is adopted to derive the discretization of the governing equations, and the θ method is employed for equations solution. A numerical …

Using Multi-Objective Optimization To Support Urban Planning, Jonas Schwaab, Kalyanmoy Deb, Erik Goodman, Sven Lautenbach, Maarten Van Strien, Adrienne Grêt-Regamey

International Congress on Environmental Modelling and Software

Globally urban growth destroys fertile soils and endangers food security. Fertile soils are often located in the vicinity of existing urban areas. Thus, preserving high-quality soils often conflicts with the objective of compact city development. Urban planners have to account for both of these and many other objectives and react to political decisions which put a higher weight on some of them. In addition, urban planners have to deal with uncertain projections on population growth and the demand for housing. We used a multi-objective evolutionary algorithm to show for a case study region in Switzerland how robust urban growth patterns …

A Study Of Non-Point Source Pollution Reduction Of Tea Garden In Taiwan Feitsui Reservoir Watershed, Chia-Chun Ho, Jen-Yang Lin

International Congress on Environmental Modelling and Software

The water quality of Feitsui Reservoir, which located in the north of Taiwan, has long been maintained mesotrophic to oligotrophic status. However, the pass rate of total phosphorous (TP) concentration of those three upstream streams, Jingualiao River, Daiyujue River, and Beishi River, have not reached 100% compliance with Class A Standard of water quality from Taiwan EPA. The main source of TP is from agriculture fertilizer, especially from the tea garden. In order to remove the non-point sources pollution, the bioretention was adopted and established at the outlet of the runoff drainage path of tea garden. The tea garden area …

Application Of The Swat Model To Investigate Surface Runoff And Nitrate Flux Towards The Mediterranean Sea: Case Of The Tafna Catchment (North-West Of Africa), Amin Zettam, Amina Taleb, Sabine Sauvage, José Miguel Sanchez-Perez, Laurie Boithias, Nouria Belaidi

International Congress on Environmental Modelling and Software

Water in North-West of Africa is an increasingly valuable resource due to high competition between agriculture, industry and drinking water supply, accentuated by frequent drought conditions in a semi-arid climate. For a few decades, the demographic explosion, the development of agriculture and industry, and the building of water infrastructures (dams) have modified the water fluxes and the biogeochemical cycle of nitrogen towards an increased production of nitrates in waters. The objectives of this study are to propose a modelling approach to quantify the contribution of the Tafna coastal watershed (North-West of Africa) to the flux of nitrates into the Mediterranean …