Earth 's magnetic field is currently changing dramatically. Is the observed decrease of the dipole moment indicating a future polarity transition? What would be the effects of such a drastic change on system Earth? Can any positive or negative effects on our biosphere or even humans be expected?

This book gives a first overview about the geomagnetic field in general and serves as an introduction into geomagnetism. As the topic of the book covers a wide range of scientific disciplines, the first chapter summarises basic principles of geomagnetism and related fields including a historic overview, instruments and measurements, paleomagnetic fields, basics of dynamo theory, etc. The contributed chapters review major results of international activities aiming at understanding the causes and effects of geomagnetic field variations in view of the questions above.

Comets consist of the most primitive material in the solar system and to understand the earliest epoch of solar system formation, we must investigate the nature of this material. Much of what we know of comets presently comes from remote sensing using Earth-based telescopes. The Rosetta mission is poised to make a dramatic advance in our understanding of comets.

The articles in this volume cover, for the first time, all aspects of planetary magnetism, from the observations made by space missions to their interpretation in terms of the properties of all the planets in the solar system. Studies of dynamo-generated magnetic fields in Mercury, the Earth, the giant planets, as well as in Ganymede, one of Jupiter's moons, are presented. Crustal magnetic field in Mars, the Mon and the Earth are described as well as magnetic fields induced in the solar system bodies. There are several articles dealing with dynamo theory and modelling and applications to the different planets.

The participation of such diverse scientific and technical disciplines as meteorology, astronomy, atmospheric electricity, ionospheric and magnetospheric physics, electromagnetic wave propagation, and radio techniques in the research of atmospherics means that results are published in scientific papers widely spread throughout the literature. This Handbook collects the latest knowledge on atmospherics and presents it in two volumes. Each chapter is written by an expert in his or her field. Topics include the physics of thunderclouds, thunder, global atmospheric electric currents, biological aspects of sferics, and various space techniques for detecting lightning within our own atmosphere as well as in the atmospheres of other planets. Up-to-date applications and methodology are detailed. Volumes I and II offer a comprehensive discussion that together will serve as an important resource for practitioners, professionals, and students alike.

The participation of such diverse scientific and technical disciplines as meteorology, astronomy, atmospheric electricity, ionospheric and magnetospheric physics, electromagnetic wave propagation, and radio techniques in the research of atmospherics means that results are published in scientific papers widely spread throughout the literature. This Handbook collects the latest knowledge on atmospherics and presents it in two volumes. Each chapter is written by an expert in his or her field. Topics include the physics of thunderclouds, thunder, global atmospheric electric currents, biological aspects of sferics, and various space techniques for detecting lightning within our own atmosphere as well as in the atmospheres of other planets. Up-to-date applications and methodology are detailed. Volumes I and II offer a comprehensive discussion that together will serve as an important resource for practitioners, professionals, and students alike.

The articles in this volume cover, for the first time, all aspects of planetary magnetism, from the observations made by space missions to their interpretation in terms of the properties of all the planets in the solar system. Studies of dynamo-generated magnetic fields in Mercury, the Earth, the giant planets, as well as in Ganymede, one of Jupiter s moons, are presented. Crustal magnetic field in Mars, the Mon and the Earth are described as well as magnetic fields induced in the solar system bodies. There are several articles dealing with dynamo theory and modelling and applications to the different planets."