Is the magnetic field around the earth decaying and what would the consequences be?

Answer 1

The Earth's magnetic field is in a constant state of flux (pun?), and it periodically reverses. Some scientists have reported a weakening of the field and this is a cause for concern, since it deflects incoming radiation from the solar wind. When it does occur, it takes several tens of thousands of years to complete, and in the meanwhile, lesser dipoles (not located at the axial poles) become the main dipoles. The consequences are that increased radiation will cause mutations in the biosphere (except for that in deep underwater environments), resulting in massive death at the new "north" dipole. Contrary to what a previous answerer said, this has nothing to do with gases emitted by man (CFCs), which were depleting the ozone layer.

Answer 2

Earth's magnetic field (and the surface magnetic field) is approximately a magnetic dipole, with one pole near the north pole and the other near the geographic south pole. An imaginary line joining the magnetic poles would be inclined by approximately 11.3° from the planet's axis of rotation. The cause of the field is probably explained by dynamo theory. The magnetic field extends several tens of thousands of kilometres into space as the magnetosphere.

The Earth's field is changing in size and position. The two poles wander independently of each other and are not at directly opposite positions on the globe. Currently the magnetic south pole is farther from the geographic south pole than the magnetic north pole is from the geographic north pole.

The field is similar to that of a bar magnet, but this similarity is superficial. The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated spins of electrons and nuclei within iron atoms. The Earth's core, however, is hotter than 1043 K, the Curie point temperature at which the orientations of spins within iron become randomized. Such randomization causes the substance to lose its magnetic field. Therefore the Earth's magnetic field is caused not by magnetised iron deposits, but mostly by electric currents in the liquid outer core (as it spins, electrons tend to stay behind, thus producing a small current).

Another feature that distinguishes the Earth magnetically from a bar magnet is its magnetosphere. At large distances from the planet, this dominates the surface magnetic field. Electric currents induced in the ionosphere also generate magnetic fields. Such a field is always generated near where the atmosphere is closest to the Sun, causing daily alterations which can deflect surface magnetic fields by as much as one degree.

The strength of the field at the Earth's surface ranges from less than 30 microteslas (0.3 gauss) in an area including most of South America and South Africa to over 60 microteslas (0.6 gauss) around the magnetic poles in northern Canada and south of Australia, and in part of Siberia.

Based upon the study of lava flows of basalt throughout the world, it has been proposed that the Earth's magnetic field reverses at intervals, ranging from tens of thousands to many millions of years, with an average interval of approximately 250,000 years. The last such event, called the Brunhes-Matuyama reversal, is theorized to have occurred some 780,000 years ago.

The earth's magnetic field strength was measured by Carl Friedrich Gauss in 1835 and has been repeatedly measured since then, showing an exponential decay with a half-life of about 1400 years.[citation needed] This indicates a relative decay of about 7 % over the last 150 years.

Animals including birds and turtles can detect the Earth's magnetic field, and use the field to navigate during migration.

Answer 3

Yeh! Try converting the earths' magnet into an electromagnet

Answer 4

yes defenitely....
all those gasses we're reliesing into the air is defenitely causing it to decay. if it continues to decay at larger amounts the weather around the world could alter. it could be catastrophic! larger, stronger storms that could destroy anything in there paths.