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1. The magnetism of the earth.
2. The study of the earth's magnetism.

ge′o·mag·net′ic (-nĕt′ĭk) adj.
ge′o·mag·net′i·cal·ly adv.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(General Physics) from a geomagnetic point of view
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
The most common ones are the widespread use of the grid-connected static power converters [2], [3], the influence of the high-voltage DC transmission [4] and the geomagnetically induced current (GIC) [5], [6].
Researchers studied 14 years of global ionospheric data and discovered that the EEJ strengthens geomagnetically induced currents.
(5.) Kappenman, J., "Low-Frequency Protection Concepts for the Electric Power Grid: Geomagnetically Induced Current (GIC) and E3 HEMP Mitigation," Meta-R-322, Metatech, January 2010.
This EMF can reach several kilovolts in long-distance electric power transmission lines (PTL) of 400-500 km, and the quasi direct current, which is also called geomagnetically induced current (GIC), circulates in electric networks [9].
Because it takes about 1 h for the solar wind to travel from the Lagrange L1 point to the magnetospheric nose, such monitoring can give about 1 h of warning time for preparing to the radiation belt enhancement, geomagnetically induced current, and other possible adverse effects of magnetic storms.
In addition, these geomagnetically induced currents or GIC hot zones are also affecting pipelines and even power lines by creating interference with the flow of electricity at the surface, and possibly the migration of gas or oil or water in the subsurface across geologic time.
Geomagnetically he is closer to the auroral zone than the United Kingdom and is much better placed to ob serve this phenomenon.
Dr Pierre Cilliers participated in an Antarctic expedition in December 2007 and an expedition to Marion Island in April 2010 to promote international research on Space Weather and is currently the SANSA PI for a project on Geomagnetically induced currents.
For example, they can temporarily divert power flow from the most severely affected parts of the grid to protect the entire grid against geomagnetically induced currents.
When a geomagnetically induced current shut down Quebec's power grid in March 1989, 5 million people had no electricity for nine hours--the result of a fast-moving chain of events that disabled nearly the entire province's power system in just 92 seconds.
Large power transformers at substations, which are grounded to the Earth, would be affected by geomagnetically induced current as a result of such a storm and fail.