Word Entries containing the term:
The minimum energy of a cosmic-ray particle which can reach the top of the atmosphere at a specified or at a particular geomagnetic latitude.
The dipole or a pair of equal and opposite electric charges or magnetic poles that are separated by a short distance which are created by the earth's magnetic field.
An instrument that can be suspended from the side of a moving ship to measure and to calculate the direction and speed of ocean currents while the ship is under way by measuring the voltage produced by the earth's magnetic field in the moving conductive seawater.
The components of the geomagnetic field at the surface of the earth.
1. The imaginary great circle on the earth's surface formed by the intersection of a plane passing through the earth's center perpendicular to the axis connecting the north and south magnetic poles.
2. That terrestrial great circle which is 90° from the geomagnetic poles.
The magnetic field observed in and around the earth.
The intensity of the magnetic field at the earth's surface is approximately 0.32 gauss at the equator and 0.62 gauss at the north pole.
A gauss equivalent to 1 maxwell per square centimeter and a maxwell is equivalent to the flux that produces one abvolt in a one-turn circuit when the flux is reduced to zero at a uniform rate in one second; while a flux is the electric or magnetic field lines of force that traverse a given cross-sectional area.
geomagnetic noise, geomagnetic interference
1. Any interference in radio communications caused by terrestrial magnetism or the earth's magnetic field.
2. Unwanted radio frequencies caused by fluctuations in the geomagnetic field of the earth.
1. Either of two antipodal (opposite) points marking the intersection of the earth's surface with the extended axis of a powerful magnet bar which is assumed to be located at the center of the earth and indicating the source of the actual magnetic field of the earth.
2. One of two regions of the earth with very high magnetic field strength, taken to be the points at which a line, drawn between the poles of a magnetic dipole generating the earth's magnetic field and extending out in both directions, would cross the earth's surface.
The north pole of a magnet; such as, a compass needle, is attracted to the geomagnetic north pole because the earth's north pole is actually a magnetic south pole (and its geomagnetic south pole is a magnetic north pole).
geomagnetic reversal, geomagnetic field reversal
Alternation of the earth's magnetic polarity or a reversal of the polarity of the earth's magnetic field which has occurred in the past as shown by the remanent magnetization found in igneous and sedimentary rocks.
The earth's internal magnetic field reverses, on average, about every 300,000 to 1 million years.
This reversal is very sudden on a geologic time scale, apparently taking about 5,000 years.
The time between reversals is highly variable, sometimes less than 40,000 years and at other times as long as 35 million years and no regularities or period times have been discovered so far.
A long interval of one polarity may be followed by a short interval of an opposite polarity.
geomagnetic secular variation, secular variation
The changes in the earth's magnetic field occurring over hundreds of years and caused by internal changes in the earth or a variation of any field or parameter which occurs over hundreds of years.
A world-wide disruption of the earth's magnetic field, distinct from regular diurnal variations; caused by ionic disturbances from solar events.
1. Temporal or short-time changes in the geomagnetic field, both long-term (secular) and short-term (transient).
2. Any change that happens to the geomagnetic field, either short or long term.