Elementary climate physics

1. The climate system 1.1. Introduction : a definition of climate 1.2. Solar radiation and the energy budget of the Earth 1.3. Atmosphere and climate 1.3.1. Evolution of the atmosphere 1.3.2. Temperature structure 1.3.3. Pressure, composition, and temperature variations and dynamics 1.4. Ocean and climate 1.4.1. Heat storage and transport 1.4.2. Hydrological cycle 1.4.3. Carbon dioxide exchange with the oceans 1.4.4. Dynamical coupling between the atmosphere and the ocean 1.5. Radiative transfer in the atmosphere 1.6. The greenhouse effect 1.7. The ozone layer and ozone depletion 1.8. Climate observations 1.9. The stability of the climate 1.9.1. Data on past fluctuations 1.9.2. Origin of the observed fluctuations 1.10. Climate modelling 1.11. Climate on other planets Further reading Questions 2. Solar radiation and the energy budget of the Earth 2.1. Sun and climate 2.2. Solar physics 2.3. Source of the Sun's energy 2.4. The radiation laws 2.5. The solar constant 2.6. The solar spectrum 2.7. Solar observations 2.8. Absorption of solar radiation in the atmosphere 2.9. The balance between incoming solar and outgoing thermal radiation Further reading Questions

3. Atmosphere and climate 3.1. Introduction 3.2. Atmospheric composition 3.3. Units of pressure 3.4. The variation of pressure with height 3.5. Vertical temperature structure 3.5.1. Tropospheric temperature profile 3.5.2. Stratospheric temperature profile 3.5.3. Observed temperature profiles 3.6. The general circulation of the atmosphere Further reading Questions 4. Clouds and aerosols 4.1. Introduction 4.2. Potential temperature and entropy 4.3. Potential energy and available potential energy 4.4. Humidity 4.5. Thermodynamics of moist air 4.6. Condensation processes and cloud formation 4.7. Growth of cloud droplets 4.8. Growth of ice crystals 4.9. Collision and coalescence 4.10. Aerosols Further reading Questions 5. Ocean and climate 5.1. Introduction 5.2. Ocean measurements 5.3. Composition of the ocean : salinity 5.4. Vertical and latitudinal structure of the ocean 5.5. The oceanic equation of state 5.6. The general circulation of the ocean 5.6.1. The Coriolis Force 5.6.2. Deep ocean dynamics : the thermohaline circulation 5.6.3. Near surface dynamics : Ekman transport and Sverdrup balance 5.7. Ocean circulation and climate change Further reading Questions

6. Radiative transfer 6.1. Introduction 6.2. Black body or cavity radiation 6.3. Atmospheric absorption and emission 6.4. Atmospheric radiative transfer 6.5. The radiative transfer equation 6.6. Integration over wavelength 6.7. Spectral properties of atmospheric gases 6.7.1. Spectral lines 6.7.2. Vibration-rotation bands 6.7.3. Band absorption formulations and band models 6.8. Radiative equilibrium models for the temperature profile 6.9. Temperature sounding and weighting functions 6.10. The inverse problem Further reading Questions 7. Earth's energy budget : the 'greenhouse' effect 7.1. Introduction 7.2. Is the atmosphere a 'greenhouse'? 7.3. The 'greenhouse' gases 7.4. Energy balance calculations 7.5. A simple physical greenhouse model 7.6. A better greenhouse model 7.6.1. The radiative-dynamical equilibrium profile revisited 7.6.2. Surface temperature versus absorber amount 7.6.3. Effect of changing albedo on surface temperature 7.7. A simple model with feedback 7.8. Conclusions Further reading Questions 8. The ozone layer 8.1. Introduction 8.2. Ultraviolet radiation in the atmosphere 8.3. Photochemistry of ozone production 8.4. Variation of ozone concentration with altitude 8.5. Catalytic cycles 8.6. Ozone measurements 8.7. The Antarctic ozone hole 8.8. The global distribution of ozone Further reading Questions

9. Climate observations by remote sensing 9.1. Introduction 9.2. Ground-based measurements 9.3. Satellite measurements 9.4. Infrared instruments for remote sounding 9.4.1. Calibration 9.4.2. Modulation 9.4.3. Radiometer optics 9.4.4. Interference filters 9.4.5. Thermal infrared detectors 9.4.6. Photon detectors 9.4.7. Electronics and telemetry 9.5. Radiometric performance 9.5.1. Signal 9.5.2. Noise 9.5.3. Signal to noise ratio 9.6. Limb viewing instruments 9.7. Contemporary satellites and instruments : three examples 9.7.1. Weather satellites : the Geostationary Operational Environmental Satellite 9.7.2. Environmental satellites : ENVISAT 9.7.3. Research satellites : UARS and EOS 9.8. Applications of remote sensing to climate studies 9.8.1. Earth's radiation budget 9.8.2. Atmospheric temperature sounding 9.8.3. Atmospheric composition and chemistry 9.8.4. Clouds, aerosols, and polar stratospheric clouds 9.8.5. Doppler wind measurements 9.8.6. Surface properties 9.8.7. Detection of climate change 9.9. The future Further reading Questions

10. Climate sensitivity and change

10.1. Introduction

10.2. Astronomical changes

10.2.1. The Milankovich cycles

10.2.2. The ice ages

10.2.3. Current changes

10.3. Variations in solar output

10.4. Changes in atmospheric composition

10.4.1. Greenhouse gases

10.4.2. Aerosols

10.4.3. Cloud and albedo variations

10.5. Ocean circulation variations

10.5.1. Changes in the thermohaline circulation

10.5.2. Rapid climate change

10.5.3. Ocean-atmosphere coupling : the El Niño-Southern Oscillation (ENSO)

10.6. Natural temperature fluctuations

10.7. Summary

Further reading

Questions

11. Climate models and predictions

11.1. Introduction

11.2. Current models and predictions

11.3. Multiple climate equilibria and sudden climate change

11.3.1. A simple radiative model

11.3.2. Box models of the ocean

11.3.3. Complex models

11.4. Problems of detection, attribution, and prediction

Further reading

Questions

12. Climate on other planets

12.1. Introduction

12.2. Mercury

12.3. Venus

12.4. Mars

12.5. Titan

12.6. The Jovian planet

12.7. Planets of other stars

12.8. Planets without stars

Further reading

Questions

13. Epilogue.