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This book gathers notes from lectures and seminars given during a three-week school on theoretical and applied data assimilation held in Les Houches in 2012. Data assimilation aims at determining as accurately as possible the state of a dynamical system by combining heterogeneous sources of information in an optimal way. Generally speaking, the mathematical methods of data assimilation describe algorithms for forming optimal combinations of observations of a system, a numerical model that describes its evolution, and appropriate prior information. Data assimilation has a long history of application to high-dimensional geophysical systems dating back to the 1960s, with application to the estimation of initial conditions for weather forecasts. It has become a major component of numerical forecasting systems in geophysics, and an intensive field of research, with numerous additional applications in oceanography and atmospheric chemistry, with extensions to other geophysical sciences. The physical complexity and the high dimensionality of geophysical systems have led the community of geophysics to make significant contributions to the fundamental theory of data assimilation. This book is composed of a series of main lectures, presenting the fundamentals of four-dimensional variational data assimilation, the Kalman filter, smoothers, and the information theory background required to understand and evaluate the role of observations; a series of specialized lectures, addressing various aspects of data assimilation in detail, from the most recent developments in the theory to the specificities of various thematic applications.

This book describes the interaction of the main biogeochemical cycles of the Earth and the physics of climate. It takes the perspective of Earth as an integrated system and provides examples of both changes in the current climate and those in the geological past. The first three chapters offer a general introduction to the context of the book, outlining the climate system as a complex interplay between biogeochemistry and physics and describing the tools available for understanding climate: observations and models. These chapters describe the basics of the system, the rates and magnitudes and the crucial aspects of biogeochemical cycles needed to understand their functioning. The second part of the book consists of four chapters that describe the physics required to understand the interaction of the climate with biogeochemistry and change. These chapters describe the physics of radiation, and that of the atmosphere, ocean circulation and thermodynamics. The interaction of aerosols with radiation and clouds is addressed in an additional chapter. The third part of the book deals with Earth’s (bio)geochemical cycles. These chapters focus on the stocks and fluxes of the main reservoirs of Earth’s biogeochemical cycles—atmosphere, land and ocean—and their role in the cycles of carbon, oxygen, nitrogen, iron, phosphorus, oxygen, sulphur and water, as well as their interactions with climate. The final two chapters describe possible mitigation and adaptation actions, in relation to recent climate agreements, but always with an emphasis on the biogeochemical aspects.

This volume is an introductory text to a range of numerical methods used today to simulate time-dependent processes in Earth science, physics, engineering, and many other fields. The physical problem of elastic wave propagation in 1D serves as a model system with which the various numerical methods are introduced and compared. The theoretical background is presented with substantial graphical material supporting the concepts. The results can be reproduced with the supplementary electronic material provided as Python codes embedded in Jupyter notebooks. The volume starts with a primer on the physics of elastic wave propagation, and a chapter on the fundamentals of parallel programming, computational grids, mesh generation, and hardware models. The core of the volume is the presentation of numerical solutions of the wave equation with six different methods: (1) the finite-difference method; (2) the pseudospectral method (Fourier and Chebyshev); (3) the linear finite-element method; (4) the spectral-element method; (5) the finite-volume method; and (6) the discontinuous Galerkin method. Each chapter contains comprehension questions, and theoretical and programming exercises. The volume closes with a discussion of domains of application and criteria for the choice of a specific numerical method, and the presentation of current challenges.

This book, based on the life and work of Joanne (Gerould) Simpson (1923–2010), charts the history of women in meteorology and the history of tropical meteorology in the context of her long and productive career as pioneer scientist, project leader, and mentor. In 1943 women had no status in meteorology, tropical weather was largely aer incognita, and Joanne Gerould, a new graduate student at the University of Chicago, had just set her sights on understanding the behavior of clouds. Establishing her career in an era of overwhelming marginalization of women in science was no easy matter, and Joanne (who published under three married names and raised three children) had to fight every step of the way. Under the mentorship of Herbert Riehl, she received a PhD degree from Chicago in 1949. Later, while working at Woods Hole, she collaborated with Riehl on their revolutionary and controversial “hot tower” hypothesis that cumulonimbus clouds were the driving force in the tropical atmosphere, providing energy to power the Hadley circulation, the trade winds, and by implication, the global circulation. The mechanism of hot towers alludes to the incessant battle between buoyancy and entrainment in tropical convection, valorizing those clouds that successfully break through the trade wind inversion to soar to the top of the troposphere. The metaphor of hot towers points to the incessant battles Joanne waged between her sky-high aspirations and the dark psychological and institutional forces dragging her down. Yet she prevailed, reaching the pinnacle of personal and professional accomplishment, especially in her years at NASA, as she conditioned the atmosphere for further breakthroughs for women in science. She is best remembered as a pioneer woman scientist, the best tropical scientist of her generation.

This book collects the text of the lectures given at the Les Houches Summer School on “Fundamental aspects of turbulent flows in climate dynamics”, held in August 2017. Leading scientists in the fields of climate dynamics, atmosphere and ocean dynamics, geophysical fluid dynamics, physics and non-linear sciences present their views on this fast growing and interdisciplinary field of research, by venturing upon fundamental problems of atmospheric convection, clouds, large-scale circulation, and predictability. Climate is controlled by turbulent flows. Turbulent motions are responsible for the bulk of the transport of energy, momentum, and water vapor in the atmosphere, which determine the distribution of temperature, winds, and precipitation on Earth. Clouds, weather systems, and boundary layers in the oceans and atmosphere are manifestations of turbulence in the climate system. Because turbulence remains as the great unsolved problem of classical physics, we do not have a complete physical theory of climate. The aim of this summer school was to survey what is known about how turbulent flows control climate, what role they may play in climate change, and to outline where progress in this important area can be expected, given today’s computational and observational capabilities. This book reviews the state-of-the-art developments in this field and provides an essential background to future studies. All chapters are written from a pedagogical perspective, making the book accessible to masters and PhD students and all researchers wishing to enter this field. It is complemented by online video of several lectures and seminars recorded during the summer school.

Drawings, illustrations, and field sketches play an important role in Earth Science since they are used to record field observations, develop interpretations, and communicate results in reports and scientific publications. Drawing geology in the field furthermore facilitates observation and maximizes the value of fieldwork. Every geologist, whether a student, academic, professional, or amateur enthusiast, will benefit from the ability to draw geological features accurately. This book describes how and what to draw in geology. Essential drawing techniques, together with practical advice in creating high quality diagrams, are described the opening chapters. How to draw different types of geology, including faults, folds, metamorphic rocks, sedimentary rocks, igneous rocks, and fossils, are the subjects of separate chapters, and include descriptions of what are the important features to draw and describe. Different types of sketch, such as drawings of three-dimensional outcrops, landscapes, thin-sections, and hand-specimens of rocks, crystals, and minerals, are discussed. The methods used to create technical diagrams such as geological maps and cross-sections are also covered. Finally, modern techniques in the acquisition and recording of field data, including photogrammetry and aerial surveys, and digital methods of illustration, are the subject of the final chapter of the book. Throughout, worked examples of field sketches and illustrations are provided as well as descriptions of the common mistakes to be avoided.

The book explains the key notions and fundamental processes in the dynamics of the fluid envelopes of the Earth (transposable to other planets), and methods of their analysis, from the unifying viewpoint of rotating shallow-water model (RSW). The model, in its one- or two-layer versions, plays a distinguished role in geophysical fluid dynamics, having been used for around a century for conceptual understanding of various phenomena, for elaboration of approaches and methods, to be applied later in more complete models, for development and testing of numerical codes and schemes of data assimilations, and many other purposes. Principles of modelling of large-scale atmospheric and oceanic flows, and corresponding approximations, are explained and it is shown how single- and multi-layer versions of RSW arise from the primitive equations by vertical averaging, and how further time-averaging produces celebrated quasi-geostrophic reductions of the model. Key concepts of geophysical fluid dynamics are exposed and interpreted in RSW terms, and fundamentals of vortex and wave dynamics are explained in Part 1 of the book, which is supplied with exercises and can be used as a textbook. Solutions of the problems are available at Editorial Office by request. In-depth treatment of dynamical processes, with special accent on the primordial process of geostrophic adjustment, on instabilities in geophysical flows, vortex and wave turbulence and on nonlinear wave interactions follows in Part 2. Recently arisen new approaches in, and applications of RSW, including moist-convective processes constitute Part 3.

Granites are emblematic rocks developed from a magma that crystallized in the Earth’s crust. They ultimately outcrop at the surface worldwide. This book, translated and updated from the original French edition Pétrologie des Granites (2011) is a modern presentation of granitic rocks from magma genesis to their crystallization at a higher level into the crust. Segregation from the source, magma ascent and shapes of granitic intrusions are also discussed, as well as the eventual formation of hybrid rocks by mingling/mixing processes and the thermomechanical aspects in country rocks around granite plutons. Modern techniques for structural studies of granites are detailed extensively. Granites are considered in their geological spatial and temporal frame, in relation with plate tectonics and Earth history from the Archaean eon. A chapter on granite metallogeny explains how elements of economic interest are concentrated during magma crystallization, and examples of Sn, Cu, F and U ore deposits are presented. Mineralogical, petrological, physical and economical aspects are developed in a succession of 14 chapters comprising a large number of high-quality illustrations. Selected examples used for the figures are derived from every continent. Special ‘info boxes’ discuss topics for those wishing to deepen the subject.

A number of extreme weather events have struck the Northern Hemisphere in recent years, from scorching heatwaves to desperately cold winters and from floods and storms to droughts and wildfires. Is this the emerging signal of climate change, and should we expect more of this? Media reports vary widely, but one mysterious agent has risen to prominence in many cases: the jet stream. The story begins on a windswept beach in Barbados, from where we follow the ascent of a weather balloon that will travel all around the world, following the jet stream. From this viewpoint we can observe the effect of the jet in influencing human life around the hemisphere, and witness startling changes emerging. What is the jet stream and how well do we understand it? How does it affect our weather and is it changing? These are the main questions tackled in this book. We learn about how our view of the wind has developed from Aristotle’s early theories up to today’s understanding. The jet is shown to be intimately connected with dramatic contrasts between climate zones and to have played a key historical role in determining patterns of trade. We learn about the basic physics underlying the jet and how this knowledge is incorporated into computer models which predict both tomorrow’s weather and the climate of future decades. We discuss how climate change is expected to affect the jet, and introduce the urgent scientific debate over whether these changes have contributed to recent extreme weather events.

Marine geochemistry uses chemical elements and their isotopes to study how the ocean works. It brings quantitative answers to questions such as: What is the deep ocean mixing rate? How much atmospheric CO₂ is pumped by the ocean? How fast are pollutants removed from the ocean? How do ecosystems react to the anthropogenic pressure? The book provides a simple introduction to the concepts (environmental chemistry, isotopes), the methods (field approach, remote sensing, modeling) and the applications (ocean circulation, carbon cycle, climate change) of marine geochemistry with a particular emphasis on isotopic tracers. Marine geochemistry is not an isolated discipline: numerous openings on physical oceanography, marine biology, climatology, geology, pollutions and ecology are proposed and provide a global vision of the ocean. It includes new topics based on ongoing research programs such as GEOTRACES, Global Carbon Project, Tara Ocean. It provides a complete outline for a course in marine geochemistry. To favor a hands-on approach, application exercises are worked out throughout the book and each chapter concludes with a set of problems based on the recent scientific literature (with solutions given at the end of the book).

Illustrated with breathtaking images of the Solar System and of the Universe around it, this book explores how the discoveries within the Solar System and of distant exoplanets come together to aid understanding of the habitability of Earth, and how this guides the search for exoplanets that could support life. The author recounts how, within two decades of the discovery of the first planets outside the Solar System in the 1990s, scientists concluded that planets are so common that most stars are orbited by them. The twelve chapters highlight what we have learned about exoplanets and how the lives of exoplanets and their stars are inextricably interwoven. Stars are the seeds around which planetary systems form. Stars provide their planets with light and warmth for as long as they shine. At the end of their lives, stars expel massive amounts of newly forged elements into deep space. That ejected material is incorporated into subsequent generations of planets. How do we learn about these distant worlds? What does the exploration of other planets tell us about the history of Earth? Can we find out what the distant future may have in store for us? What do we know about exoworlds and starbirth, and where do migrating hot Jupiters, polluted white dwarfs, and free-roaming nomad planets fit in? What does all that have to do with the habitability of Earth and the possibility of finding extraterrestrial life? And how did the globe-spanning network of the sciences begin to answer all these questions?

Oxford Weather and Climate since 1767 provides a detailed description and analysis of the weather records made at the Radcliffe Observatory in Oxford, the longest continuous series of single-site weather records in Britain and one of the longest in the world. The earliest records date from 1767, and daily records are unbroken since November 1813. The records allow the reconstruction of 200-year temperature and rainfall series and places the Oxford records in the context of long-term climate change. In this, the first full publication of the entire dataset, the long Oxford record is both celebrated and described. Detailed commentaries on weather by month and by season are provided, including numerous contemporary documentary and photographic evidence of past weather events. Drought and flood feature prominently, but so too do fog, frost, ice and snow. Some long-term changes are obvious, such as the increase in air temperature over the period of the instrumental record, but the impact on the growing season and the ability to grow grapes commercially near Oxford are less well known.

This is a physics textbook describing, at a college level, the physics and technology needed to provide sustainable long-term energy, past the era of fossil fuels. A summary is given of global power generation and consumption, with estimates of times until conventional fuels will deplete. Sustainable power sources, largely those coming from the Sun directly or indirectly, are described. As sustainable energy must preserve the Earth’s atmosphere and climate, key elements of these topics are included. Key energy technologies in this book include photovoltaics, wind turbines and the electric power grid, for which the underlying physics is developed. Nuclear fusion is described in the context of the Sun’s energy generation, in a brief description of tokamak fusion reactors, and also to introduce ideas of quantum physics needed for adequate treatment of photovoltaic devices. Energy flow in and out of the Earth’s atmosphere is discussed, including the role of greenhouse gas impurities arising from fossil fuel burning as trapping heat and raising the Earth’s temperature. Discussion is included of the Earth’s climatic history and future. Exercises are included for each chapter.

This book is concerned with the exploitation of polarisation effects in electromagnetic wave scattering for applications in remote sensing. It combines, for the first time, the topics of scattering polarimetry and interferometry, and is written in three main sections. In the first four chapters it provides detailed coverage of all major topics of polarimetry, including its basis in electromagnetic scattering theory, the topic of decomposition theorems, and a detailed analysis of the entropy/alpha approach to characterising polarisation effects. In the next chapter it provides a brief introduction to radar interferometry, before developing in three chapters the important new topic of polarimetric interferometry. In this way it provides a complete treatment of the subject, suitable for those working in interferometry who wish to know about polarimetry, or vice versa, as well as those new to the topic who are seeking a one-stop comprehensive treatment of the subject. The emphasis throughout is on the application of these techniques to remote sensing and the book concludes with a set of practical examples to illustrate the theoretical ideas. Useful appendices on matrix algebra, unitary groups and stochastic signal analysis are provided.

This book deals with the theory of atmospheric radiation and radiation transfer, and its application to current problems related to the processes that maintain the global climate of the Earth. It combines aspects of solar radiation; atmospheric radiation; radiation budget theory and measurements; photochemistry; instruments; satellite observations; and prediction models; and applies them to understanding the Earth's climate and current concerns over climate change. Radiation theory is fundamental to the development of climate prediction models, and to measurement techniques for monitoring the Earth's energy budget and making remote sensing observations related to climate from satellites. Such theory and measurements are at the core of the climate change debate. This book describes in detail the basic physics used in the radiative transfer codes that are a key part of climate models. The basic principles are extended to the atmospheres of the Earth and the other planets, illustrating the greenhouse effect and other radiation-based phenomena at work. Several chapters deal with the techniques and measurements for monitoring the Earth's radiation budget, and thus tracking global change and its effects. Remote sensing instruments on satellites and the theory of remote sensing are also covered.

The Earth that sustains us today was born out of a few remarkable, near-catastrophic revolutions, started by biological innovations and marked by global environmental consequences. The revolutions have certain features in common, such as an increase in complexity, energy utilisation, and information processing by life. This book describes these revolutions, showing the fundamental interdependence of the evolution of life and its non-living environment. We would not exist unless these upheavals had led eventually to ‘successful’ outcomes – meaning that after each one, at length, a new stable world emerged. The current planet-reshaping activities of our species may be the start of another great Earth system revolution, but there is no guarantee that this one will be successful. The book explains what a successful transition through it might look like, and whether we are wise enough to steer such a course. It places humanity in context as part of the Earth system, using a new scientific synthesis to illustrate our debt to the deep past and our potential for the future.

In industrially developed countries, energy is used primarily for three things—maintaining a comfortable environment in buildings, transporting people and goods and manufacturing products. Each accounts for about one-third of the total primary energy use. Controlling the indoor temperature accounts for most of the energy use in buildings. Therefore, this strongly depends on the local climate. Electricity accounts for a high proportion of the energy transfer in developed countries. The problem is that electricity cannot easily be stored, and that supply therefore has to match demand. This makes the use of intermittent renewables such as solar and wind particularly challenging. Transportation efficiency can be measured by the energy used to move a person or a tonne of freight over a given distance, but there is also the journey time to consider. Transportation, with the exception of trains, is constrained by the energy density and convenience of fuels, and it is hard to beat liquid hydrocarbons as fuels. Materials that are dug out of the earth are nearly always oxides, but we want the element itself. The reduction process inevitably uses energy and produces carbon dioxide. Even growing crops requires energy in addition to that provided by sunlight. A meat-based diet requires significantly higher energy inputs than a vegetarian diet. Growing crops for fuel is a poor use of land, the problem being that crops do not grow fast enough. Policy should ultimately be based on what works from a physics and engineering viewpoint, and not on legislation that mandates the use of favoured renewable energy sources.

This work is a critical update of the most recent and innovative developments of the avalanche science. It aims at re-founding it on clear scientific bases, from field observations and experiments up to strong mathematical and physical analysis and modeling. It points out snow peculiarities, regarding both static mechanical properties and flow dynamics, that may strongly differ from those of compact solids for the former, and of Newtonian fluids for the latter. It analyzes the general processes involved in avalanche release, in terms of brittle fracture and ductile plasticity, specific friction laws, flow of healable granular materials, percolation concepts, cellular automata, scale invariance, criticality, theory of dynamical systems, bifurcations, etc. As a result, slab triggering (including remote triggering) can be summarized by the “slab avalanche release in 4 steps” concept, based on weak layer local collapse and subsequent propagation driven by slab weight. The frequent abortion of many incipient avalanches is easily explained in terms of snow grain dynamical healing. Sluffs and full-depth avalanches are also analyzed. Such advances pave the way for significant progress in risk evaluation procedures. In the present context of a speeding-up climate warming, possible evolutions of snow cover extent and stability are also tentatively discussed. We show how, in mountainous areas, the present analysis can be extended to other gravitational failures (rock-falls, landslides) that are likely to take over from avalanches in such circumstances. The text is supported by on-line links to field experiments and lectures on triggering mechanisms, risk management, and decision making.

This book presents numerical methods to solve soil physics problems using computers. It starts with the theory and then shows how to use Python code to solve the problems. Most soil physics books focus on deriving rather than solving the differential equations for mass and energy transport in the soil–plant–atmosphere continuum. The focus of this book is on solutions. Agricultural and biological scientists usually have a good working knowledge of algebra and calculus, but not of differential equations. Here numerical procedures are used to solve differential equations. This allows the solution of quite difficult problems with fairly simple mathematical tools. Numerical methods convert differential into algebraic equations, which can be solved using conventional methods of linear algebra. Each chapter introduces soil physics concepts. Most chapters then go on to develop computer programs to solve the equations and illustrate the points made in the discussion. Exercises at the end of each chapter help the reader practice using the concepts introduced in the chapter. The exercises and computer programs are an integral part of the presentation, and readers are strongly encouraged to experiment with each model until both its working and the concepts it teaches are familiar.

This book develops both spectroscopy and radiative transfer for planetary atmospheric composition in a rigorous and quantitative sense for students of atmospheric and/or planetary science. Spectroscopic field measurements including satellite remote sensing have advanced rapidly in recent years, and are being increasingly applied to provide information about planetary atmospheres. Examples include systematic observation of the atmospheric constituents that affect weather, climate, biogeochemical cycles, air quality on Earth, as well as the physics and evolution of planetary atmospheres in our solar system and beyond. Understanding atmospheric spectroscopy and radiative transfer is important throughout the disciplines of atmospheric science and planetary atmospheres to understand principles of remote sensing of atmospheric composition and the effects of atmospheric composition on climate. Atmospheric scientists need an understanding of the details, strength and weaknesses of the spectroscopic measurement sources. Those in remote sensing require an understanding of the information content of the measured spectra that are needed for the design of retrieval algorithms and for developing new instrumentation.