Particularly intense lightning discharges can produce transient luminous events above thunderclouds, termed sprites, elves and jets. These short lived optical emissions in the mesosphere can reach from the tops of thunderclouds up to the ionosphere; they provide direct evidence of coupling from the lower atmosphere to the upper atmosphere. Sprites are arguably the most dramatic recent discovery in solar-terrestrial physics. Shortly after the first ground based video recordings of sprites, observations on board the Space Shuttle detected sprites and elves occurring all around the world. These reports led to detailed sprite observations in North America, South America, Australia, Japan, and Europe. Subsequently, sprites were detected from other space platforms such as the International Space Station and the ROCSAT satellite. During the past 15 years, more than 200 contributions on sprites have been published in the scientific literature to document this rapidly evolving new research area.

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Contents.Contributing Authors.Preface. Introduction to the Physics of Sprites, Elves and Intense Lightning Discharges.-1.1 Rasic Properties of the Atmosphere.-1.2 Risc Theory of Electrical Phenomena Occurring in the Atmosphere.-1.3 The Properties of Sprites, Elves and Intense Lightning Discharges.-1.4 Introduction to Theoriesand Numerical Modelling of Sprites.-1.5 Conclusions. Acknowledgements. The Meteorology of Transient Luminous an Introduction and Overview.-2.1 Introduction.-2.2 Observations of Convective Phenomena.-2.3 A Brief History of TEE Observations.-2.4 Characteristics of TLE-Parent Lirhthinc and Storms.-2.5 Research Frontiers Acknowledgments. The Microphysical and Electrical Properties of Sprite- Producing Thunderstorms.-3.1 Introduction.-3.2 The Non-Inductive Charging Process in Thunderclouds.-3.3 Cloud Scale Charge Structure Possible with the Non-Inductive Mechanism.-3.4 The Electrical Structure Inside Sprite-Producing Storms in Summer- time.-3.5 The Electrical Structure inside Sprite-Producing Storms in Wintertime.-3.6 Gaps in Knowledge and Future Needs Acknowledgments. Global Thunderstorm Activity.-4.1The Earth's Energy Balance.-4.2 The General Circulation of the Atmosphere.-4.3 Frontal Thunderstorms in Mid-Latitude Regions.- 4.4 Global Observations of Lightning.-4.5 The Global Atmospheric Electric Circuit.-4.6 Future Directions.-Imaging Systems in the Research.-5.1 Introduction to Low Light Imaging.-5.2 The Spritewatch Systems.-5.3 Conclusions. Spacecraft Based Studies of Transient Luminous Events -6.1 Introduction.-6.2 FORMOSAT-2 Satellite and the ISUAL Instrumen.-6.3 Initial Observations with ISUAL 6.4 Summary Acknowledgments. Observations of Sprites From Space at the Nadir: The LSO (Lightning and Sprite Observations) Experiment on Board of the International Space Station.-7.1 Introduction.-7.2 Spectral Differentiation of Sprite and Lightning Emissions.-7.3 Experiment.-7.4 Observations.-7.5 Perspectives. Remote Sensing of the Upper Atmosphereby VLF.-8.1 Ionospheric Conductivity.-8.2 Sources of VLF Electromagnetic (EM) Waves.-8.3 VLF Propagation in the Earth-Ionosphere Waveguide.-8.4 Relaxation of High-Altitude Ionospheric Modifications.-8.5 Summary. Measurements of Lightning Parameters from Remote Electromagnetic Fields.- 9.1 Background and Motivation.-9.2 Remote Lightning Parameter Measurements.-9.3 Data Analysis Techniques.-9.4 Summary. Location and Electrical Properties of Sprite-Producing Lightning from a single Elf Site.-10.1 Introduction.-10.2 Locating Distant ELF Sources and Quantifying their Electrical Properties.-10.3 Winter TLEs and Associated Electromagnetic Phenomena in Japan.-10.4 Conclusion Acknowledgments. Calibrated Radiance Measurements with an Air-Filled Glow Discharge Tube: Application to Sprites in the Mesosphere.-11.1 Introduction.-11 .2 Methodology 11.3 Optical Spectrum.-11 .4 Radiance Response to Power and Current Density.-11.5 Estimates of Bulk Plasma Conductivity.-11.6 Application to Current Flow in Sprites.-11 7 Conclusion . Acknowledgments Theoretical Modeling of Sprites and Jets.-12.1 Introduction.-12.2 Classification of Breakdown Mechanisms in Air.-12.3 Physical Mechanism and Numerical Modeling of Sprites.-12.4 Physical Mechanism and Numerical Modeling of Blue Jets, Blue Starters and Gigantic Jets.-12.5 Unsolved Problems. Acknowledgements. On the Modeling of Sprites and Sprite Producing Clouds in the Global Electric Circuit.-13.1 Introduction,.-13.2 Time dependent Electric field in the Conducting Atmosphere.-13.3 Modeling of the Lower Positive Charge Layer in the Stratified Region.-13.4 Global Electric Circuit Implications.-13.5 Conclusion and Outlook for Promising Future Work. Acknowledgements. Actual Problems of Thundercloud Electrodynamics.-14. 1 Introduction.-14.2 Electric Field Generation in an Atmospheric Convective Cell.-14.3 Fine Structure of Electric Fields in a Thundercloud.-14.4 Acceleration of Relativistic Electrons during a Thunderstorm.-14.5 Conclusions Acknowledgments. Poster Abstracts.-15.1 Introduction.-15.2 Observations from the Ground.-15.3 Observations from Space.-15.4 Theoretical Modelling. Index