Download or read book Parameter Sensitivity and Interaction in Complex Environmental Models written by Thomas Michael Grieb and published by . This book was released on 2000 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Global Sensitivity Analysis written by Andrea Saltelli and published by John Wiley & Sons. This book was released on 2008-02-28 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Complex mathematical and computational models are used in all areas of society and technology and yet model based science is increasingly contested or refuted, especially when models are applied to controversial themes in domains such as health, the environment or the economy. More stringent standards of proofs are demanded from model-based numbers, especially when these numbers represent potential financial losses, threats to human health or the state of the environment. Quantitative sensitivity analysis is generally agreed to be one such standard. Mathematical models are good at mapping assumptions into inferences. A modeller makes assumptions about laws pertaining to the system, about its status and a plethora of other, often arcane, system variables and internal model settings. To what extent can we rely on the model-based inference when most of these assumptions are fraught with uncertainties? Global Sensitivity Analysis offers an accessible treatment of such problems via quantitative sensitivity analysis, beginning with the first principles and guiding the reader through the full range of recommended practices with a rich set of solved exercises. The text explains the motivation for sensitivity analysis, reviews the required statistical concepts, and provides a guide to potential applications. The book: Provides a self-contained treatment of the subject, allowing readers to learn and practice global sensitivity analysis without further materials. Presents ways to frame the analysis, interpret its results, and avoid potential pitfalls. Features numerous exercises and solved problems to help illustrate the applications. Is authored by leading sensitivity analysis practitioners, combining a range of disciplinary backgrounds. Postgraduate students and practitioners in a wide range of subjects, including statistics, mathematics, engineering, physics, chemistry, environmental sciences, biology, toxicology, actuarial sciences, and econometrics will find much of use here. This book will prove equally valuable to engineers working on risk analysis and to financial analysts concerned with pricing and hedging.

Download or read book Modelling of Pollutants in Complex Environmental Systems written by Grady Hanrahan and published by ILM Publications. This book was released on 2010 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental modelling has enjoyed a long tradition, but there is a defined need to continually address both the power and the limitations of such models, as well as their quantitative assessment. This book showcases modern environmental modelling methods, the basic theory behind them and their incorporation into complex environmental investigations. It highlights advanced computing technologies and how they have led to unprecedented and adaptive modelling, simulation and decision-support tools to study complex environmental systems, and how they can be applied to current environmental concerns. This volume is essential reading for researchers in academia, industry and government-related bodies who have a vested interest in all aspects of environmental modelling. Features include: A range of modern environmental modelling techniques are described by experts from around the world, including the USA, Canada, Australia, Europe and Thailand; many examples from air, water, soil/sediment and biological matrices are covered in detail throughout the book; key chapters are included on modelling uncertainty and sensitivity analysis; and, a selection of figures are provided in full colour to enable greater comprehension of the topics discussed.

Download or read book Environmental Modelling written by John Wainwright and published by John Wiley & Sons. This book was released on 2013-01-22 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Simulation models are an established method used to investigate processes and solve practical problems in a wide variety of disciplines. Central to the concept of this second edition is the idea that environmental systems are complex, open systems. The authors present the diversity of approaches to dealing with environmental complexity and then encourage readers to make comparisons between these approaches and between different disciplines. Environmental Modelling: Finding Simplicity in Complexity 2nd edition is divided into four main sections: An overview of methods and approaches to modelling. State of the art for modelling environmental processes Tools used and models for management Current and future developments. The second edition evolves from the first by providing additional emphasis and material for those students wishing to specialize in environmental modelling. This edition: Focuses on simplifying complex environmental systems. Reviews current software, tools and techniques for modelling. Gives practical examples from a wide variety of disciplines, e.g. climatology, ecology, hydrology, geomorphology and engineering. Has an associated website containing colour images, links to WWW resources and chapter support pages, including data sets relating to case studies, exercises and model animations. This book is suitable for final year undergraduates and postgraduates in environmental modelling, environmental science, civil engineering and biology who will already be familiar with the subject and are moving on to specialize in the field. It is also designed to appeal to professionals interested in the environmental sciences, including environmental consultants, government employees, civil engineers, geographers, ecologists, meteorologists, and geochemists.

Download or read book Sensitivity Analysis in Earth Observation Modelling written by George P. Petropoulos and published by Elsevier. This book was released on 2016-10-07 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sensitivity Analysis in Earth Observation Modeling highlights the state-of-the-art in ongoing research investigations and new applications of sensitivity analysis in earth observation modeling. In this framework, original works concerned with the development or exploitation of diverse methods applied to different types of earth observation data or earth observation-based modeling approaches are included. An overview of sensitivity analysis methods and principles is provided first, followed by examples of applications and case studies of different sensitivity/uncertainty analysis implementation methods, covering the full spectrum of sensitivity analysis techniques, including operational products. Finally, the book outlines challenges and future prospects for implementation in earth observation modeling. Information provided in this book is of practical value to readers looking to understand the principles of sensitivity analysis in earth observation modeling, the level of scientific maturity in the field, and where the main limitations or challenges are in terms of improving our ability to implement such approaches in a wide range of applications. Readers will also be informed on the implementation of sensitivity/uncertainty analysis on operational products available at present, on global and continental scales. All of this information is vital in the selection process of the most appropriate sensitivity analysis method to implement. Outlines challenges and future prospects of sensitivity analysis implementation in earth observation modeling Provides readers with a roadmap for directing future efforts Includes case studies with applications from different regions around the globe, helping readers to explore strengths and weaknesses of the different methods in earth observation modeling Presents a step-by-step guide, providing the principles of each method followed by the application of variants, making the reference easy to use and follow

Download or read book Advanced Numerical Methods for Complex Environmental Models Needs and Availability written by István Faragó and published by Bentham Science Publishers. This book was released on 2013-12-10 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: High air pollution levels pose a significant threat to plants, animals and human beings. Efforts by researchers are directed towards keeping air pollution levels below well defined ‘critical‘ levels in order to maintain a sustainable atmosphere and environmental system. The application of advanced mathematical models is important for researchers to achieve this goal as efficiently as possible. Mathematical models can be used to predict answers to many important questions about the environment. This application comes with several complex theoretical and practical obstacles which need to be resolved. A successfully applicable mathematical model needs to enable researchers to • Mathematically describe all important physical and chemical processes. • Apply fast and sufficiently accurate numerical methods. • Ensure that the model runs efficiently on modern high speed computers. • Use high quality input data, both meteorological data and emission inventories, in the runs. • Verify the model results by comparing them with reliable measurements taken in different parts of the spatial domain of the model. • Carry out long series of sensitivity experiments to check the response of the model to changes of different key parameters. • Visualize and animate the output results in order to make them easily understandable even to non-specialists. This monograph thoroughly describes mathematical methods useful for various situations in environmental modeling - including finite difference methods, splitting methods, parallel computation, etc. - and provides a framework for resolving problems posed in relation to the points listed above. Chapters are written by well-known specialists making this book a handy reference for researchers, university teachers and students working and studying in the areas of air pollution, meteorology, applied mathematics and computer science.

Download or read book A Review of Parameter Sensitivity Methods Applicable to Ecosystem Models written by K. A. Rose and published by . This book was released on 1981 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Predictive Modeling of Environmental Systems written by Elias C. Massoud and published by . This book was released on 2017 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2013, the World Meteorological Organization (WMO) urged the global community for coordinated international action against accelerating and potentially devastating climate change. Preliminary data indicated that CO2 levels increased more between 2012 and 2013 than during any other year since 1984, and this was possibly related to reduced uptake by the Earth's biosphere in addition to the steadily increasing emissions from the Earth's surface. In the upcoming decades, it will be critical for scientists and policy makers to not only resolve the problem of carbon emissions by assessing human behavior, but also to understand as thoroughly as possible the underlying coupled processes of the Earth's atmosphere and biosphere in order to adequately measure and estimate the fluxes of carbon, water, and energy that are dictating the climatic trends we observe today. Fortunately, our ability to understand Earth's processes and predict climate change is improving.This thesis covers a suite of environmental models and numerical methods to disentangle information found both in observed data as well as model simulations. Various methods are applied such as parameter estimation with Markov Chain Monte Carlo (MCMC), state estimation with data assimilation using the Ensemble Kalman Filter (EnKF), and sensitivity analysis of model parameters using the Fourier Amplitude Sensitivity Test (FAST), which all in one way or another offer treatments to predictive uncertainty. Furthermore, applying these methods on more sophisticated and complex models can be impossible sometimes due to their high CPU costs; in this thesis model emulators are built using Polynomial Chaos Expansion (PCE) to reduce the computational burden for various environmental models. Overall, our goal in this dissertation is to present what tools are currently available for making predictions of environmental systems, with emphasis on maintaining accuracy of model simulations when compared to observed data, optimizing the efficiency of computationally heavy models to minimize their run time costs, and obtaining fidelity of model structures to properly represent the underlying hydrologic, biophysical, and biogeochemical processes occurring on our Earth.

Download or read book Calibration and Uncertainty Analysis for Complex Environmental Models written by John Doherty and published by . This book was released on 2015-05-17 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sensitivity Analysis in Practice written by Andrea Saltelli and published by John Wiley & Sons. This book was released on 2004-07-16 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sensitivity analysis should be considered a pre-requisite for statistical model building in any scientific discipline where modelling takes place. For a non-expert, choosing the method of analysis for their model is complex, and depends on a number of factors. This book guides the non-expert through their problem in order to enable them to choose and apply the most appropriate method. It offers a review of the state-of-the-art in sensitivity analysis, and is suitable for a wide range of practitioners. It is focussed on the use of SIMLAB – a widely distributed freely-available sensitivity analysis software package developed by the authors – for solving problems in sensitivity analysis of statistical models. Other key features: Provides an accessible overview of the current most widely used methods for sensitivity analysis. Opens with a detailed worked example to explain the motivation behind the book. Includes a range of examples to help illustrate the concepts discussed. Focuses on implementation of the methods in the software SIMLAB - a freely-available sensitivity analysis software package developed by the authors. Contains a large number of references to sources for further reading. Authored by the leading authorities on sensitivity analysis.

Download or read book Fundamentals of Ecological Modelling written by Sven Erik Jørgensen and published by Elsevier. This book was released on 2001 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cover -- Contents -- Preface -- Acknowledgements -- Chapter 1. Introduction -- 1.1 Physical and Mathematical Models -- 1.2 Models as a Management Tool -- 1.3 Models as a Scientific Tool -- 1.4 Models and Holism -- 1.5 The Ecosystem as an Object for Research -- 1.6 Outline of the Book -- 1.7 The Development of Ecological and Environmental Models -- 1.8 State of the Art in the Application of Models -- Chapter 2. Concepts of Modelling -- 2.1 Introduction -- 2.2 Modelling Elements -- 2.3 The Modelling Procedure -- 2.4 Types of Model -- 2.5 Selection of Model Type -- 2.6 Selection of Model Complexity and Structure -- 2.7 Verification -- 2.8 Sensitivity Analysis -- 2.9 Parameter Estimation -- 2.10 Validation -- 2.11 Ecological Modelling and Quantum Theory -- 2.12 Modelling Constraints -- Problems -- Chapter 3. Ecological Processes -- 3A.1 Space and Time Resolution -- 3A.2 Mass Transport -- 3A.3 Mass Balance -- 3A.4 Energetic Factors -- 3A.5 Settling and Resuspension -- 3B.1 Chemical Reaction ...

Download or read book Environmental Modelling written by Jo Smith and published by Oxford University Press. This book was released on 2007-01-18 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The global environment is a complex mix of interlinked processes, about which observation can tell us a great deal. This book shows how modelling can be used to explain experimental observations, and how these observations - and data gathered - can be extrapolated to explain novel situations. It also illustrates how models are actively applied.

Download or read book Rainfall runoff Modelling in Gauged and Ungauged Catchments written by Thorsten Wagener and published by World Scientific. This book was released on 2004 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: This important monograph is based on the results of a study on the identification of conceptual lumped rainfall-runoff models for gauged and ungauged catchments. The task of model identification remains difficult despite decades of research. A detailed problem analysis and an extensive review form the basis for the development of a Matlab? modelling toolkit consisting of two components: a Rainfall-Runoff Modelling Toolbox (RRMT) and a Monte Carlo Analysis Toolbox (MCAT). These are subsequently applied to study the tasks of model identification and evaluation. A novel dynamic identifiability approach has been developed for the gauged catchment case. The theory underlying the application of rainfall-runoff models for predictions in ungauged catchments is studied, problems are highlighted and promising ways to move forward are investigated. Modelling frameworks for both gauged and ungauged cases are developed. This book presents the first extensive treatment of rainfall-runoff model identification in gauged and ungauged catchments.

Download or read book Environmental Modeling written by Mike J. Barnsley and published by CRC Press. This book was released on 2007-02-13 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasingly used to represent climatic, biogeochemical, and ecological systems, computer modeling has become an important tool that should be in every environmental professional’s toolbox. Environmental Modeling: A Practical Introduction is just what it purports to be, a practical introduction to the various methods, techniques, and skills required for computerized environmental modeling. Exploring the broad arena of environmental modeling, the book demonstrates how to represent an environmental problem in conceptual terms, formalize the conceptual model using mathematical expressions, convert the mathematical model into a program that can be run on a desktop or laptop computer, and examine the results produced by the computational model. Equally important, the book imparts skills that allow you to develop, implement, and experiment with a range of computerized environmental models. The emphasis is on active engagement in the modeling process rather than on passive learning about a suite of well-established models. The author takes a practical approach throughout, one that does not get bogged down in the details of the underlying mathematics and that encourages learning through “hands on” experimentation. He provides a set of software tools and data sets that you can use to work through the various examples and exercises presented in each chapter, as well as presentational material and handouts for course tutors. Comprehensive and up-to-date, the book discusses how computational models can be used to represent environmental systems and illustrates how such models improve understanding of the ways in which environmental systems function.

Download or read book Uncertainties in Environmental Modelling and Consequences for Policy Making written by Philippe Baveye and published by Springer Science & Business Media. This book was released on 2009-05-14 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mathematical modelling has become in recent years an essential tool for the prediction of environmental change and for the development of sustainable policies. Yet, many of the uncertainties associated with modelling efforts appear poorly understood by many, especially by policy makers. This book attempts for the first time to cover the full range of issues related to model uncertainties, from the subjectivity of setting up a conceptual model of a given system, all the way to communicating the nature of model uncertainties to non-scientists and accounting for model uncertainties in policy decisions. Theoretical chapters, providing background information on specific steps in the modelling process and in the adoption of models by end-users, are complemented by illustrative case studies dealing with soils and global climate change. All the chapters are authored by recognized experts in their respective disciplines, and provide a timely and uniquely comprehensive coverage of an important field.

Download or read book Estimation Problems in Complex Field Studies with Deep Interactions written by Krzysztof M. Sakrejda and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Field studies that measure vital rates in context over extended time periods are a cornerstone of our understanding of population processes. These studies inform us about the relationship between biological process and environmental noise in an irreplaceable way. These data sets bring ``big data'' and ``big model'' challenges, which limit the application of standard software (e.g., \textbf{BUGS}). The environmental sensitivity of vital rates is also expected to exhibit interactions and non-linearity, which typically result in difficult model selection questions in large data sets. Finally, long-term ecological data sets often contain complex temporal structure. In commonly applied discrete-time models complex temporal structure forces the analyst to make many competing decisions about discretizing time, which add complexity to any analysis and confuse the interpretation of parameters. I tackle these problems in three ways: 1) I apply and improve current state of the art statistical algorithms and software (Hamiltonian Monte Carlo with the NUTS sampler implemented in \textbf{Stan}) to implement the estimation of vital rates from mark-recapture data in a large Atlantic salmon data set; 2) I extend continuous-time time-to-event models with continuous estimated rate functions to mark-recapture and emigration data; and 3) I apply simple local regression to the estimation of vital rates to turn the model-selection problem resulting from interactions and non-linearity into an estimation problem, which is solved by the estimation algorithm. For each model I present methods for visualizing the results in biologically meaningful terms and use these for model criticism.

Download or read book Environmental Foresight and Models written by M.B. Beck and published by Elsevier. This book was released on 2002-03-20 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Policy-makers and the public, it has famously been said, are more interested in the possibility of non-linear dislocations and surprises in the behaviour of the environment than in smooth extrapolations of current trends. The International Task Force in Forecasting Environmental Change (1993-1998) dedicated its work to developing procedures of model building capable of addressing our palpable concerns for substantial change in the future. This volume discusses the immense challenges that such structural change presents - that the behaviour of the environment may become radically different from that observed in the past - and investigates the potentially profound implications for model development.Drawing upon case histories from the Great Lakes, acidic atmospheric deposition and, among others, the urban ozone problem, this discourse responds to a new agenda of questions. For example: "What system of 'radar' might we design to detect threats to the environment lying just beyond the 'horizon'?" and "Are the seeds of structural change identifiable within the record of the recent past?"Meticulously researched by leading environmental modellers, this milestone volume engages vigorously with its subject and offers an animated account of how models can begin to take into consideration the significant threats and uncertainties posed by structural change.