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1
Zohdi, Tarek I. An introduction to modeling and simulation of particulate flows. Philadelphia, PA: Society for Industrial and Applied Mathematics, 2007.
2
Randall, Clive William. The application of contact mechanics to the numerical simulation of particulate material. Birmingham: Aston University. Department of Civil Engineering, 1989.
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Davidson, Moreira, e Vilhena Marco, a cura di. Air pollution and turbulence: Modeling and applications. Boca Raton: Taylor & Francis, 2010.
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Flanagan, Thomas Bernard. Signal controlled roundabouts: An investigation into the efficiency of signal controlled roundabouts utilizing simulation techniques with particular reference to junctions with three approaches. Bradford, England: University of Bradford, 1987.
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Office, General Accounting. Air pollution: EPA's actions to resolve concerns with the fine particulate monitoring program : report to the Chairman, Subcommittee on VA, HUD, and Independent Agencies, Committee on Appropriations, House of Representatives. [Washington, D.C.]: The Office, 1999.
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Lenhard, Johannes. Computer Simulation. A cura di Paul Humphreys. Oxford University Press, 2015. http://dx.doi.org/10.1093/oxfordhb/9780199368815.013.42.
Abstract (sommario):
This article interprets computer simulation modeling as a new type of mathematical modeling that comprises a number of interdependent components, among them experimentation, visualization, and adaptability. Furthermore, it is argued, simulation modeling can be characterized as a particular style of reasoning, namely a combinatorial style, that assembles and balances elements from different other styles. Two examples are discussed that exemplify the transformative force of this style: what counts as “understanding phenomena” and what counts as a “solution.” Both are seminal pieces of traditional mathematical modeling and both are transformed, if not inverted, in simulation modeling. Finally, some challenges are considered that computer simulations pose for philosophy of science.
7
Allen, Michael P., e Dominic J. Tildesley. Some tricks of the trade. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198803195.003.0005.
Abstract (sommario):
This chapter concentrates on practical tips and tricks for improving the efficiency of computer simulation programs. This includes the effect of using truncated and shifted potentials, and the use of table look-up and neural networks for calculating potentials. Approaches for speeding up simulations, such as the Verlet neighbour list, linked-lists and multiple timestep methods are described. The chapter then proceeds to discuss the general structure of common simulation programs; in particular the choice of the starting configuration and the initial velocities of the particles. The chapter also contains details of the overall approach to organising runs, storing the data, and checking that the program is working correctly.
8
Birks, Daniel. Computer Simulations. A cura di Gerben J. N. Bruinsma e Shane D. Johnson. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780190279707.013.36.
Abstract (sommario):
In recent years, the field of social simulation has been dominated by the individual, or agent-based, computational model (ABM). ABMs provide unique means to explore complex social systems by allowing researchers to construct explicit models of the individual actors and interactions that make them up - people, peer groups, companies, nations, trade, reproduction, victimization, and so on, This chapter aims to provide the reader with a primer in the social simulation method and in particular the application of ABM in the field of environmental criminology. It begins by discussing the rationale behind the ABM approach. Subsequently, drawing on two illustrative simulations, it summarizes fundamental processes involved in designing, constructing, verifying, calibrating, validating, and utilizing ABM. It concludes by discussing some of the overarching strengths and limitations of the approach, and by discussing several areas of research that might aid in furthering the use of ABM within the field of environmental criminology.
9
Zohdi, T. I. An Introduction to Modeling and Simulation of Particulate Flows (Computational Science and Engineering). SIAM, Society for Industrial and Applied Mathematics, 2007.
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Computational Fluid And Particle Dynamics In The Human Respiratory System. Springer, 2012.
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Moreira, Davidson, e Marco Vilhena. Air Pollution and Turbulence: Modeling and Applications. Taylor & Francis Group, 2009.
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Moreira, Davidson, e Marco Vilhena. Air Pollution and Turbulence. Taylor & Francis Group, 2009.
13
Friedlander, Jennifer. An Uncertain Indeterminacy. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780190676124.003.0004.
Abstract (sommario):
This chapter focuses on the controversy surrounding Yale University senior Aliza Shvartz, who made international headlines when reports circulated that her senior-year art project documented a year in which she frequently tried to impregnate herself while taking herbs to induce a miscarriage. At the heart of the uproar lies a fundamental uncertainty as to the reality of the documented event. In particular, claims that the piece was a “hoax” imply that she performed a mere dissimulation rather than, as Shvartz herself suggests, a true simulation. This case also serves as an opportunity to assess the political implications of artistic forms in which tensions between claims of realism and deception emerge, and it helps us to attend to difficulties encountered in the deployment of both dissimulation and simulation as strategies for upsetting the social order.
14
Clegg, G. Teacher and pupil perceptions of the microcomputer in the primary school with particular reference to simulation and adventure game programs. 1988.
15
Eriksson, Olle, Anders Bergman, Lars Bergqvist e Johan Hellsvik. Implementation. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198788669.003.0007.
Abstract (sommario):
In this chapter, we will present the technical aspects of atomistic spin dynamics, in particular how the method can be implemented in an actual computer software. This involves calculation of effective field and creation of neighbour lists for setting up the geometry of the system of interest as well as choosing a suitable integrator scheme for the SLL (or SLLG) equation. We also give examples of extraction and processing of relevant observables that are common output from simulations. Atomistic spin dynamics simulations could be a computationally heavy tool but it is also very well adapted for modern computer architectures like massive parallel computing and/or graphics processing units and we provide examples how to utilize these architectures in an efficient manner. We use our own developed software UppASD as example, but the discussion could be applied to any other atomistic spin dynamics software.
16
Phan-Thien, Nhan, e Sangtae Kim. Microstructures in Elastic Media. Oxford University Press, 1994. http://dx.doi.org/10.1093/oso/9780195090864.001.0001.
Abstract (sommario):
This monograph describes various methods for solving deformation problems of particulate solids, taking the reader from analytical to computational methods. The book is the first to present the topic of linear elasticity in mathematical terms that will be familiar to anyone with a grounding in fluid mechanics. It incorporates the latest advances in computational algorithms for elliptic partial differential equations, and provides the groundwork for simulations on high performance parallel computers. Numerous exercises complement the theoretical discussions, and a related set of self-documented programs is available to readers with Internet access. The work will be of interest to advanced students and practicing researchers in mechanical engineering, chemical engineering, applied physics, computational methods, and developers of numerical modeling software.
17
Millstein, Roberta. Probability in Biology. A cura di Alan Hájek e Christopher Hitchcock. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199607617.013.27.
Abstract (sommario):
I examine the concept of “fitness” in the philosophy of evolutionary biology to show how discussions of probability in biology can go wrong, and right. Many of the critiques of the propensity interpretation of fitness have focused on the mathematical aspects of fitness; re-focusing on several aspects of the propensity interpretation of probability more generally can help to address these concerns. I conclude with some general lessons for thinking about probability in biology. The propensity interpretation of fitness, properly understood, solves the explanatory circularity problem and the mismatch problem, andalso withstands many other problems. Fitness is the propensity for organisms to survive and reproduce in particular environments and in particular populations. Fitness values can be described in terms of distributions of propensities and can be modeled for any number of generations using computer simulations. Fitness is a causal concept. Relative fitness is what matters for natural selection.
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Kanduč, M., A. Schlaich, E. Schneck e R. R. Netz. Interactions between biological membranes: theoretical concepts. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198789352.003.0012.
Abstract (sommario):
In this chapter we review the various types of generic (non-specific) forces acting between lipid membranes in an aqueous environment and discuss the underlying mechanisms, with particular focus on the competing roles of enthalpic and entropic contributions. The interaction free energy (or interaction potential) is typically the result of a subtle interplay of several, often antagonistic contributions with comparable magnitude. First, we will briefly introduce the underlying physics of various kinds of surface–surface interactions, starting with theories of van der Waals and undulation interactions, covering electrostatics, depletion, and order–parameter fluctuation effects as well. We then turn our attention to a strong and universal repulsive force at small membrane–membrane separations, namely the hydration interaction. It has been under debate and investigation for decades and is not well captured by continuum approximations, thus here we will mainly rely on atomistic simulation techniques.
19
Campbell, John, Joey Huston e Frank Krauss. QCD to All Orders. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199652747.003.0005.
Abstract (sommario):
This chapter centres around the treatment of QCD emissions to all orders. After introductory remarks about the analytic properties of the radiation pattern, some of the most striking phenomenological consequences of non-trivial quantum effects, in particular, the angular ordering property of QCD, are highlighted. Next, analytic resummation techniques are considered, expanding on the treatment of transverse momentum resummation from Chapter 2, and introducing the idea of threshold resummation. BFKL resummation, which resums large logarithms emerging in the high-energy limit, is also introduced. In the second part of this chapter, the probabilistic simulation of QCD radiation through the parton shower is discussed. After a detailed introduction to different schemes and algorithms, the discussion of the combination of the parton shower with fixed-order matrix elements beyond the Born approximation is considered, with a discussion of matching with NLO calculations and the merging with multijet matrix elements.
20
Kubek, Maria M., e Zhong Li, a cura di. Autonomous Systems 2018. VDI Verlag, 2018. http://dx.doi.org/10.51202/9783186862105.
Abstract (sommario):
To meet the expectations raised by the terms Industry 4.0, Industrial Internet and Internet of Things, real innovations are necessary, which can be brought about by information processing systems working autonomously. Owing to their growing complexity and their embedding in ever-changing environments, their design becomes increasingly critical. Thus, the many topics addressed in this book range from data integration on hardware level to methods for security and safety of data and to stochastic methods, data interferences as well as machine learning and search in decentralised systems. Their validity is proven by extensive simulation results. Also, applications for methods from deep learning and neurocomputing are presented. The sustainable management of energy systems using intelligent methods of self-organisation and learning is dealt with in the second major part of this book. As in these particular settings, the assessment of network vulnerabilities plays a crucial role, respective ...
21
Gallagher, Shaun. The Practice of Thinking. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198794325.003.0010.
Abstract (sommario):
This chapter addresses what is sometimes called the ‘scaling-up’ problem. The challenge is to show how enactivism can explain higher-order cognition that may involve memory, imagination, reflection, and abstract thinking. The chapter is framed around three interventions. First, it develops an enactivist account of affordance-based imagining, with reference to concepts of simulation and pretend play. Second, reflective thinking is conceived as a skillful practice, a concept introduced with reference to the recent McDowell–Dreyfus debate. Finally, this enactivist conception of thinking as practice is applied to mathematical reasoning, seemingly the most abstract of cognitive accomplishments. Just as we can understand the movement possibilities of our bodies as tracing out physical affordances to be found in particular environments, the principles and operations of geometry and mathematics trace out cultural affordances that allow us to solve problems, to communicate at abstract levels, to model knowledge, and thereby to transform our environments.
22
Humphreys, Paul. Computational Economics. A cura di Don Ross e Harold Kincaid. Oxford University Press, 2009. http://dx.doi.org/10.1093/oxfordhb/9780195189254.003.0013.
Abstract (sommario):
Computational economics is a relatively new research technique in economics, but it is inexorably taking its place alongside the more traditional methods of general theory, abstract modeling, data analysis, and the more recent experimental economics. Perhaps because of its relative newness, the term computational economics currently has no determinate meaning. In contemporary use, it refers to a heterogeneous cluster of techniques implemented on concrete digital computers ranging from the numerical solution of the Black-Scholes partial differential equation for pricing options through automated trading strategies to agent-based computer simulations of the evolution of cooperation. Because of this heterogeneity, it is not possible to provide a comprehensive coverage of the topic in this article. Another reason for this restricted scope is that many of the methods used in computational economics have considerable technical interest but no particular philosophical relevance.
23
Laver, Michael, e Ernest Sergenti. The Evolutionary Dynamics of Decision Rule Selection. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691139036.003.0008.
Abstract (sommario):
This chapter extends the survival-of-the-fittest evolutionary environment to consider the possibility that new political parties, when they first come into existence, do not pick decision rules at random but instead choose rules that have a track record of past success. This is done by adding replicator-mutator dynamics to the model, according to which the probability that each rule is selected by a new party is an evolving but noisy function of that rule's past performance. Estimating characteristic outputs when this type of positive feedback enters the dynamic model creates new methodological challenges. The simulation results show that it is very rare for one decision rule to drive out all others over the long run. While the diversity of decision rules used by party leaders is drastically reduced with such positive feedback in the party system, and while some particular decision rule is typically prominent over a certain period of time, party systems in which party leaders use different decision rules are sustained over substantial periods.
24
Bennett, D. Scott. Teaching the Scientific Study of International Processes. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190846626.013.314.
Abstract (sommario):
The Scientific Study of International Processes (SSIP) is an approach aimed at teaching of international politics scientifically. Teaching scientifically means teaching students how to use evidence to support or disprove some particular logical argument or hypothesis that reaches some level of generalization about relationships between concepts. Closely related to simply asking what evidence there is, is teaching students to address the breadth, depth, and quality of that evidence. The scientific approach may also draw attention to the logic of arguments and policies. Are policies, positions, and the arguments behind them logical? Or is some policy or position based on assumptions that are not logically related, or only true if certain auxiliary assumptions hold true? Teaching methods for SSIP include comparative case studies, experiments and surveys, data sets, and game theory and simulation. Instructors also face several challenges when seeking to teach scientifically, and in particular when they try to make time to teach methodology as part of an international politics course. Some problems are relatively easily overcome just by focusing on effective teaching. Other are unique to SSIP and cannot be dealt with quite so easily. Among these are the need to appeal to a broad audience, and dealing with students' negative reactions to the term “science” and the constraint of finite time in a course.
25
Baillo, Amparo, Antonio Cuevas e Ricardo Fraiman. Classification methods for functional data. A cura di Frédéric Ferraty e Yves Romain. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780199568444.013.10.
Abstract (sommario):
This article reviews the literature concerning supervised and unsupervised classification of functional data. It first explains the meaning of unsupervised classification vs. supervised classification before discussing the supervised classification problem in the infinite-dimensional case, showing that its formal statement generally coincides with that of discriminant analysis in the classical multivariate case. It then considers the optimal classifier and plug-in rules, empirical risk and empirical minimization rules, linear discrimination rules, the k nearest neighbor (k-NN) method, and kernel rules. It also describes classification based on partial least squares, classification based on reproducing kernels, and depth-based classification. Finally, it examines unsupervised classification methods, focusing on K-means for functional data, K-means for data in a Hilbert space, and impartial trimmed K-means for functional data. Some practical issues, in particular real-data examples and simulations, are reviewed and some selected proofs are given.
26
Wing, Ian Sue, e Edward J. Balistreri. Computable General Equilibrium Models for Policy Evaluation and Economic Consequence Analysis. A cura di Shu-Heng Chen, Mak Kaboudan e Ye-Rong Du. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780199844371.013.7.
Abstract (sommario):
This chapter reviews recent applications of computable general equilibrium (CGE) modeling in the analysis and evaluation of policies that affect interactions among multiple markets. At the core of this research is a particular approach to the data and structural representations of the economy, elaborated through the device of a canonical static multiregional model. This template is adapted and extended to shed light on the structural and methodological foundations of simulating dynamic economies, incorporating “bottom-up” representations of discrete production activities, and modeling contemporary theories of international trade with monopolistic competition and heterogeneous firms. These techniques are motivated by policy applications including trade liberalization, development, energy policy and greenhouse gas mitigation, the impacts of climate change and natural disasters, and economic integration and liberalization of trade in services.
27
Clark, James S., Dave Bell, Michael Dietze, Michelle Hersh, Ines Ibanez, Shannon LaDeau, Sean McMahon et al. Assessing the probability of rare climate events. A cura di Anthony O'Hagan e Mike West. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780198703174.013.16.
Abstract (sommario):
This article focuses on the use of Bayesian methods in assessing the probability of rare climate events, and more specifically the potential collapse of the meridional overturning circulation (MOC) in the Atlantic Ocean. It first provides an overview of climate models and their use to perform climate simulations, drawing attention to uncertainty in climate simulators and the role of data in climate prediction, before describing an experiment that simulates the evolution of the MOC through the twenty-first century. MOC collapse is predicted by the GENIE-1 (Grid Enabled Integrated Earth system model) for some values of the model inputs, and Bayesian emulation is used for collapse probability analysis. Data comprising a sparse time series of five measurements of the MOC from 1957 to 2004 are analysed. The results demonstrate the utility of Bayesian analysis in dealing with uncertainty in complex models, and in particular in quantifying the risk of extreme outcomes.
28
Stamenova, M., e S. Sanvito. Atomistic spin-dynamics. A cura di A. V. Narlikar e Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533046.013.7.
Abstract (sommario):
This article reviews recent advances towards the development of a truly atomistic time-dependent theory for spin-dynamics. The focus is on the s-d tight-binding model [where conduction electrons (s) are exchange-coupled to a number of classical spins (d)], including electrostatic corrections at the Hartree level, as the underlying electronic structure theory. In particular, the article considers one-dimensional (1D) magnetic atomic wires and their electronic structure, described by means of the s-d model. The discussion begins with an overview of the model spin Hamiltonian, followed by molecular-dynamics simulations of spin-wave dispersion in a s-d monoatomic chain and spin impurities in a non-magnetic chain. The current-induced motion in a magnetic domain wall (DW) is also explored, along with how an electric current can affect the magnetization landscape of a magnetic nano-object. The article concludes with an assessment of spin-motive force, and especially whether a driven magnetization dynamics can generate an electrical signal.
29
Primiero, Giuseppe. On the Foundations of Computing. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198835646.001.0001.
Abstract (sommario):
This book is a technical, historical, and conceptual investigation into the three main methodological approaches to the computational sciences: mathematical, engineering, and experimental. Part I explores the background behind the formal understanding of computing, originating at the end of the nineteenth century, and it invesitagtes the formal origins and conceptual development of the notions of computation, algorithm, and program.Part II overviews the construction of physical devices to performautomated tasks and it considers associated technical and conceptual issues. It starts with the design and construction of the first generation of computingmachines, explores their evolution and progress in engineering (for both hardware and software), and investigates their theoretical and conceptual problems. Part III analyses the methods and principles of experimental sciences founded on computationalmethods. It studies the use ofmachines to performscientific tasks,with particular reference to computer models and simulations. Each part aims at defining a notion of computational validity according to the corresponding methodological approach.
30
Sprenger, Jan, e Stephan Hartmann. Bayesian Philosophy of Science. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780199672110.001.0001.
Abstract (sommario):
“Bayesian Philosophy of Science” addresses classical topics in philosophy of science, using a single key concept—degrees of beliefs—in order to explain and to elucidate manifold aspects of scientific reasoning. The basic idea is that the value of convincing evidence, good explanations, intertheoretic reduction, and so on, can all be captured by the effect it has on our degrees of belief. This idea is elaborated as a cycle of variations about the theme of representing rational degrees of belief by means of subjective probabilities, and changing them by a particular rule (Bayesian Conditionalization). Partly, the book is committed to the Carnapian tradition of explicating essential concepts in scientific reasoning using Bayesian models (e.g., degree of confirmation, causal strength, explanatory power). Partly, it develops new solutions to old problems such as learning conditional evidence and updating on old evidence, and it models important argument schemes in science such as the No Alternatives Argument, the No Miracles Argument or Inference to the Best Explanation. Finally, it is explained how Bayesian inference in scientific applications—above all, statistics—can be squared with the demands of practitioners and how a subjective school of inference can make claims to scientific objectivity. The book integrates conceptual analysis, formal models, simulations, case studies and empirical findings in an attempt to lead the way for 21th century philosophy of science.
31
Dill-Shackleford, Karen E., e Cynthia Vinney. Finding Truth in Fiction. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190643607.001.0001.
Abstract (sommario):
Being a fan of a popular film, television, or book franchise is something most of us enjoy. But, we may not be familiar with the scientific study of fictional narrative or of fandom. In this book, two media psychologists reveal the sometimes-paradoxical idea that fiction helps us find truth in our real lives. Whether you consider yourself a fan or whether you find yourself thinking of a particular fictional scene for inspiration, you are not alone. Perfectly sane people regularly admit that their favorite stories are important to them. Although journalists sometimes assume that the interest in the fictional world is a sign of trouble, the authors enthusiastically disagree. Because story worlds are social simulations, people use them to work out their values, decide how to handle similar situations, and even decide what kind of person they want to be. Although films and shows are widely spoken of as diversions or as escapism, there are many ways that they aren’t trivial at all. In this book, the authors explore how to understand the identity of a favorite character and the actor who plays the character. Are they the same person? They also delve into the nitty gritty of mental models for story worlds and timeless story arcs such as the hero’s journey. The moments that strike people as important can change as they age and move through different life stages. The authors’ conclusion: fans are not crazy. What fans are is human.
32
Grush, Rick, e Lisa Damm. Cognition and the Brain. A cura di Eric Margolis, Richard Samuels e Stephen P. Stich. Oxford University Press, 2012. http://dx.doi.org/10.1093/oxfordhb/9780195309799.013.0012.
Abstract (sommario):
The article explores the relationship between cognition and the brain. Some researches indicate that emotions provide information, anticipate future responses, influence reasoning strategy, index value, and direct attention toward particular objects but few psychologists have attempted to incorporate these results into an integrative general theory of cognition and emotion. Antonio Damasio claims that emotions are primarily representations of somatic states, including visceral and musculoskeletal, at the psychological level. The relationship between the event type and the associated emotional reaction is learned so that when the same type of event is encountered, or the same type of action considered, it can induce the corresponding emotion and the valance of that emotion can influence how the agent behaves in that situation. Damasio argued that somatic markers help facilitate reasoning by providing a rapid processing of potential decision outcomes based on immediate endorsement or rejection, which then helps constrain the decision-making space to a manageable size for which it becomes reasonable to employ more traditional means of evaluation such as cost-benefit analysis on the remaining options. Berthoz argued that the brain is a simulator of action and a generator of hypotheses such that anticipating and predicting the consequences of actions based on the remembered past is one of the basic properties of the brain.
33
Tibaldi, Stefano, e Franco Molteni. Atmospheric Blocking in Observation and Models. Oxford University Press, 2018. http://dx.doi.org/10.1093/acrefore/9780190228620.013.611.
Abstract (sommario):
The atmospheric circulation in the mid-latitudes of both hemispheres is usually dominated by westerly winds and by planetary-scale and shorter-scale synoptic waves, moving mostly from west to east. A remarkable and frequent exception to this “usual” behavior is atmospheric blocking. Blocking occurs when the usual zonal flow is hindered by the establishment of a large-amplitude, quasi-stationary, high-pressure meridional circulation structure which “blocks” the flow of the westerlies and the progression of the atmospheric waves and disturbances embedded in them. Such blocking structures can have lifetimes varying from a few days to several weeks in the most extreme cases. Their presence can strongly affect the weather of large portions of the mid-latitudes, leading to the establishment of anomalous meteorological conditions. These can take the form of strong precipitation episodes or persistent anticyclonic regimes, leading in turn to floods, extreme cold spells, heat waves, or short-lived droughts. Even air quality can be strongly influenced by the establishment of atmospheric blocking, with episodes of high concentrations of low-level ozone in summer and of particulate matter and other air pollutants in winter, particularly in highly populated urban areas.Atmospheric blocking has the tendency to occur more often in winter and in certain longitudinal quadrants, notably the Euro-Atlantic and the Pacific sectors of the Northern Hemisphere. In the Southern Hemisphere, blocking episodes are generally less frequent, and the longitudinal localization is less pronounced than in the Northern Hemisphere.Blocking has aroused the interest of atmospheric scientists since the middle of the last century, with the pioneering observational works of Berggren, Bolin, Rossby, and Rex, and has become the subject of innumerable observational and theoretical studies. The purpose of such studies was originally to find a commonly accepted structural and phenomenological definition of atmospheric blocking. The investigations went on to study blocking climatology in terms of the geographical distribution of its frequency of occurrence and the associated seasonal and inter-annual variability. Well into the second half of the 20th century, a large number of theoretical dynamic works on blocking formation and maintenance started appearing in the literature. Such theoretical studies explored a wide range of possible dynamic mechanisms, including large-amplitude planetary-scale wave dynamics, including Rossby wave breaking, multiple equilibria circulation regimes, large-scale forcing of anticyclones by synoptic-scale eddies, finite-amplitude non-linear instability theory, and influence of sea surface temperature anomalies, to name but a few. However, to date no unique theoretical model of atmospheric blocking has been formulated that can account for all of its observational characteristics.When numerical, global short- and medium-range weather predictions started being produced operationally, and with the establishment, in the late 1970s and early 1980s, of the European Centre for Medium-Range Weather Forecasts, it quickly became of relevance to assess the capability of numerical models to predict blocking with the correct space-time characteristics (e.g., location, time of onset, life span, and decay). Early studies showed that models had difficulties in correctly representing blocking as well as in connection with their large systematic (mean) errors.Despite enormous improvements in the ability of numerical models to represent atmospheric dynamics, blocking remains a challenge for global weather prediction and climate simulation models. Such modeling deficiencies have negative consequences not only for our ability to represent the observed climate but also for the possibility of producing high-quality seasonal-to-decadal predictions. For such predictions, representing the correct space-time statistics of blocking occurrence is, especially for certain geographical areas, extremely important.
34
Liu, Xiaodong, e Libin Yan. Elevation-Dependent Climate Change in the Tibetan Plateau. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.593.
Abstract (sommario):
As a unique and high gigantic plateau, the Tibetan Plateau (TP) is sensitive and vulnerable to global climate change, and its climate change tendencies and the corresponding impact on regional ecosystems and water resources can provide an early alarm for global and mid-latitude climate changes. Growing evidence suggests that the TP has experienced more significant warming than its surrounding areas during past decades, especially at elevations higher than 4 km. Greater warming at higher elevations than at lower elevations has been reported in several major mountainous regions on earth, and this interesting phenomenon is known as elevation-dependent climate change, or elevation-dependent warming (EDW).At the beginning of the 21st century, Chinese scholars first noticed that the TP had experienced significant warming since the mid-1950s, especially in winter, and that the latest warming period in the TP occurred earlier than enhanced global warming since the 1970s. The Chinese also first reported that the warming rates increased with the elevation in the TP and its neighborhood, and the TP was one of the most sensitive areas to global climate change. Later, additional studies, using more and longer observations from meteorological stations and satellites, shed light on the detailed characteristics of EDW in terms of mean, minimum, and maximum temperatures and in different seasons. For example, it was found that the daily minimum temperature showed the most evident EDW in comparison to the mean and daily maximum temperatures, and EDW is more significant in winter than in other seasons. The mean daily minimum and maximum temperatures also maintained increasing trends in the context of EDW. Despite a global warming hiatus since the turn of the 21st century, the TP exhibited persistent warming from 2001 to 2012.Although EDW has been demonstrated by more and more observations and modeling studies, the underlying mechanisms for EDW are not entirely clear owing to sparse, discontinuous, and insufficient observations of climate change processes. Based on limited observations and model simulations, several factors and their combinations have been proposed to be responsible for EDW, including the snow-albedo feedback, cloud-radiation effects, water vapor and radiative fluxes, and aerosols forcing. At present, however, various explanations of the mechanisms for EDW are mainly derived from model-based research, lacking more solid observational evidence. Therefore, to comprehensively understand the mechanisms of EDW, a more extensive and multiple-perspective climate monitoring system is urgently needed in the areas of the TP with high elevations and complex terrains.High-elevation climate change may have resulted in a series of environmental consequences, such as vegetation changes, permafrost melting, and glacier shrinkage, in mountainous areas. In particular, the glacial retreat could alter the headwater environments on the TP and the hydrometeorological characteristics of several major rivers in Asia, threatening the water supply for the people living in the adjacent countries. Taking into account the climate-model projections that the warming trend will continue over the TP in the coming decades, this region’s climate change and the relevant environmental consequences should be of great concern to both scientists and the general public.