Exoplanetary Atmospheres: Theoretical Concepts and Foundations

✍ Scribed by Kevin Heng

• Publisher: Princeton University Press
• Year: 2017
• Tongue: English
• Leaves: 290
• Series: Princeton Series in Astrophysics; 30
• Category: Library

✦ Synopsis

The study of exoplanetary atmospheres—that is, of planets orbiting stars beyond our solar system—may be our best hope for discovering life elsewhere in the universe. This dynamic, interdisciplinary field requires practitioners to apply knowledge from atmospheric and climate science, astronomy and astrophysics, chemistry, geology and geophysics, planetary science, and even biology. Exoplanetary Atmospheres provides an essential introduction to the theoretical foundations of this cutting-edge new science.

Exoplanetary Atmospheres covers the physics of radiation, fluid dynamics, atmospheric chemistry, and atmospheric escape. It draws on simple analytical models to aid learning, and features a wealth of problem sets, some of which are open-ended. This authoritative and accessible graduate textbook uses a coherent and self-consistent set of notation and definitions throughout, and also includes appendixes containing useful formulae in thermodynamics and vector calculus as well as selected Python scripts.

Exoplanetary Atmospheres prepares PhD students for research careers in the field, and is ideal for self-study as well as for use in a course setting.

• The first graduate textbook on the theory of exoplanetary atmospheres
• Unifies knowledge from atmospheric and climate science, astronomy and astrophysics, chemistry, planetary science, and more
• Covers radiative transfer, fluid dynamics, atmospheric chemistry, and atmospheric escape
• Provides simple analytical models and a wealth of problem sets
• Includes appendixes on thermodynamics, vector calculus, tabulated Gibbs free energies, and Python scripts
• Solutions manual (available only to professors)

✦ Table of Contents

Contents
Foreword
Preface
1.
Observations of Exoplanetary Atmospheres: A Theorist’s Review of Techniques in Astronomy
1.1 The birth of exoplanetary science
1.2 Transits and occultations
1.3 Radial velocity measurements
1.4 Direct imaging
1.5 Gravitational microlensing
1.6 Future missions and telescopes
2.
Introduction to Radiative Transfer
2.1 The optical depth: The most fundamental quantity in radiative transfer
2.2 Basic quantities in radiative transfer
2.3 The radiative transfer equation
2.4 Simple solutions of the radiative transfer equation
2.5 A practical checklist for radiative transfer calculations
2.6 Clouds
2.7 Atmospheric retrieval
2.8 Problem sets
3.
The Two-Stream Approximation of Radiative Transfer
3.1 What is the two-stream approximation?
3.2 The radiative transfer equation and its moments
3.3 Two-stream solutions with isotropic scattering
3.4 The scattering phase function
3.5 Two-stream solutions with non-isotropic scattering
3.6 Different closures of the two-stream solutions
3.7 The diffusion approximation for radiative transfer
3.8 Problem sets
4.
Temperature-Pressure Profiles
4.1 A myriad of atmospheric effects: Greenhouse warming and antigreenhouse cooling
4.2 The dual-band or double-gray approximation
4.3 The radiative transfer equation and the scattering parameter
4.4 Treatment of shortwave radiation
4.5 Treatment of longwave radiation
4.6 Assembling the pieces: Deriving the general solution
4.7 Exploration of different atmospheric effects
4.8 Milne’s solution and the convective adiabat
4.9 Problem sets
5.
Atmospheric Opacities: How to Use a Line List
5.1 From spectroscopic line lists to synthetic spectra
5.2 The Voigt profile
5.3 The quantum physics of spectral lines
5.4 The million- to billion-line radiative transfer challenge
5.5 Different types of mean opacities
5.6 Problem sets
6. Introduction to Atmospheric Chemistry
6.1 Why is atmospheric chemistry important?
6.2 Basic quantities: Gibbs free energy, equilibrium constant, rate coefficients
6.3 Chemical kinetics: Treating chemistry as a set of mass conservation equations
6.4 Self-consistent atmospheric chemistry, radiation and dynamics: A formidable computational challenge
6.5 Problem sets
7.
A Hierarchy of Atmospheric Chemistries
7.1 A hierarchy of models for understanding atmospheric chemistry
7.2 Equilibrium chemistry with only hydrogen
7.3 Equilibrium C-H-O chemistry: Forming methane, water, carbon monoxide and acetylene
7.4 Equilibrium C-H-O chemistry: Adding carbon dioxide
7.5 Equilibrium C-H-O chemistry: Adding ethylene
7.6 Problem sets
8.
Introduction to Fluid Dynamics
8.1 Why is the study of fluids relevant to exoplanetary atmospheres?
8.2 What exactly is a fluid?
8.3 The governing equations of fluid dynamics
8.4 Potential temperature and potential vorticity
8.5 Dimensionless fluid numbers
8.6 Problem sets
9.
Deriving the Governing Equations of Fluid Dynamics
9.1 Preamble
9.2 The mass continuity equation (mass conservation)
9.3 The Navier-Stokes equation (momentum conservation)
9.4 The thermodynamic equation (energy conservation)
9.5 The conservation of potential vorticity
9.6 Various approximate forms of the governing equations of fluid dynamics
9.7 Magnetohydrodynamics
9.8 Problem sets
10.
The Shallow Water System: A Fluid Dynamics Lab on Paper
10.1 A versatile fluid dynamics laboratory on paper
10.2 Deriving the shallow water equations
10.3 Gravity as the restoring force: The generation of gravity waves
10.4 Friction in an atmosphere: Molecular viscosity and Rayleigh drag
10.5 Forcing the atmosphere: Stellar irradiation
10.6 Like plucking a string: Alfvén waves
10.7 Rotation: The generation of Poincaré and Rossby waves
10.8 General coupling of physical effects
10.9 Shallow atmospheres as quantum harmonic oscillators
10.10 Shallow water systems and exoplanetary atmospheres
10.11 Problem sets
11.
The de Laval Nozzle and Shocks
11.1 What is the de Laval nozzle?
11.2 What are shocks?
11.3 What does the de Laval nozzle teach us about shocks?
11.4 Applications to, and consequences for, exoplanetary atmospheres
11.5 Problem sets
12.
Convection, Turbulence and Fluid Instabilities
12.1 Fluid motion induced by physically unstable configurations
12.2 Hot air rises and cold air sinks: Schwarzschild’s criterion for convective stability
12.3 A simplified “theory” of convection: Mixing length theory
12.4 Implementing convection in numerical calculations: Convective adjustment schemes
12.5 A simple “theory” of turbulence: The scaling laws of Kolmogorov
12.6 Water over oil: The Rayleigh-Taylor instability
12.7 Shearing fluids: The Kelvin-Helmholtz instability
12.8 Weather at mid-latitudes: The baroclinic instability
12.9 Problem sets
13.
Atmospheric Escape
13.1 The Knudsen number and Jeans parameter
13.2 Jeans escape
13.3 The classical Parker wind solution
13.4 Non-isothermal Parker winds: Using the nozzle solutions
13.5 Detailed processes: Photo-ionization, radiative cooling and nonthermal mechanisms
13.6 Problem sets
14.
Outstanding Problems of Exoplanetary Atmospheres
Appendix A: Summary of Standard Notation
Appendix B: Essential Formulae of Vector Calculus
Appendix C: Essential Formulae of Thermodynamics
Appendix D: Gibbs Free Energies of Various Molecules and Re-actions
Appendix E: Python Scripts for Generating Figures
Bibliography
Index