Dipole model of the Earth's magnetic field

About: Dipole model of the Earth's magnetic field is a research topic. Over the lifetime, 2756 publications have been published within this topic receiving 83021 citations.

The structure of the heliospheric current sheet: 1978–1982

Abstract: The structure of the heliospheric magnetic field changes substantially during the 11 year sunspot cycle. Its configuration for the period 1976 through 1982 using a potential field model was calculated. The structure during the rising phase, maximum, and early decline of sunspot cycle 21, from 1978 to 1982 is considered.

A quantitative magnetospheric model derived from spacecraft magnetometer data

Abstract: Quantitative models of the external magnetospheric field were derived by making least-squares fits to magnetic field measurements from four IMP satellites The data were fit to a power series expansion in the solar magnetic coordinates and the solar wind-dipole tilt angle, and thus the models contain the effects of seasonal north-south asymmetries The expansions are divergence-free, but unlike the usual scalar potential expansions, the models contain a nonzero curl representing currents distributed within the magnetosphere Characteristics of four models are presented, representing different degrees of magnetic disturbance as determined by the range of Kp values The latitude at the earth separating open polar cap field lines from field lines closing on the dayside is about 5 deg lower than that determined by previous theoretically-derived models At times of high Kp, additional high latitude field lines are drawn back into the tail

Transition region magnetic field and polar magnetic disturbances.

Abstract: Transition region magnetic field and polar magnetic disturbances, comparing Explorer XII DATA with ground measurements from Arctic observatories

Motions in the magnetosphere of the Earth

Abstract: The conditions determining the dynamical behavior of the ionized gas in the outer atmosphere of the earth are discussed. It is proposed to call this region in which the magnetic field of the earth dominates the ‘magnetosphere.’ Observations by Van Allen and others indicate that this zone reaches out to between 5 and 10 earth radii, depending on the degree of magnetic disturbance. It is shown that the existence of an insulating layer at the base of this region, namely the non-ionized atmosphere, completely changes the type of control exerted by the magnetic field, allowing a class of motions to occur freely without the need to overcome any magnetic forces. The extent to which such motions may occur is discussed, and some of the indications from airglow and magnetic observations are mentioned. The theory predicts that, at the level of the F2 layer and above, most motions will show strict symmetry between the two base points of a magnetic line of force.

The magnetic field of the earth : paleomagnetism, the core, and the deep mantle

Abstract: History of Geomagnetism and Paleomagnetism: Discovery of the Main Magnetic Elements. Fossil Magnetism and the Magnetic Field in the Past. Investigations of the External Magnetic Field. Origin of the Earth's Magnetic Field. The Present Geomagnetic Field: Analysis and Description from Historical Observations: Magnetic Elements and Charts. Spherical Harmonic Description of the Earth's Magnetic Field. Uniqueness and Other Mathematical Problems. Geomagnetic Secular Variation. The External Magnetic Field. Foundations of Paleomagnetism: Rock Magnetism. Magnetic Mineralogy. Paleomagnetic Directions and Poles. Paleointensity Methods. Age Determinations. The Recent Geomagnetic Field: Paleomagnetic Observations: Archeomagnetic Results. Analysis of Recent Lake Sediments. Geomagnetic Excursions. The Geomagnetic Power Spectrum. Reversals of the Earth's Magnetic Field: Evidence for Field Reversal. Marine Magnetic Anomalies. Analysis of Reversal Sequences. Polarity Transitions. The Time-Averaged Paleomagnetic Field: Geocentric Axial Dipole Hypothesis. Second-Order Terms. Variation in the Earth's Dipole Moment. Paleosecular Variation from Lavas (PSVL). Processes and Properties of the Earth's Deep Interior: Basic Principles: Seismic Properties of the Earth's Interior. Chemical and Physical Properties. Thermodynamic Properties of the Earth's Deep Interior. Thermal History Models. Non-dynamo Models for the Earth's Magnetic Field. Fluid Mechanics Fundamentals. Energy Sources. Introduction to Dynamo Theory: The Dynamo Problem. The Magnetic Induction Equation. The a and w Effects of Dynamo Theory. Waves in Dynamo Theory. Symmetries in Dynamo Theory. Theories for Geomagnetic Secular Variations and magnetic Field Reversals. Dynamo Theory: Vector Spherical Harmonics. Kinematic Dynamos. Cowling's Theorem and Other Constraints. Turbulence in the Core. Dynamo Waves. Dynamics of the Geodynamo. The Magnetic Fields of the Sun, Moon, and Planets: Origin of the Solar System. The Sun. The Moon. Meteorites. Magnetic Fields of the Planets. Geomagnetic Relevance. Examples of Synthesis: Fluid Velocities in the Core. Core-Mantle Coupling: Length of Day. Paleomagnetism and Dynamo Theory. Variations at the Core-Mantle Boundary and the Earth's Surface. Appendices. References. Subject Index.