Technically Speaking

This computer simulation shows the Earth’s interior as its magnetic field reverses, perhaps because of changes in the flow of molten iron in the core.

Scientist have known for some time that the Earth’s magnetic field has been getting weaker over the last few hundred years. It has been declining at an alarming rate. When I first heard about this phenomenon, scientist were predicting that the field would disappear within a few hundred years and this would leave earth as an unbearable planet for life. The magnetic field is our first line of defense from the sun’s intense radiation. It deflects a great amount of the radiation back into space, without it we (the animal life of the planet) would either die off or mutate into organisms that can cope with the radiation.

Scientist have found that there is evidence that the magnetic field has been weak before. The evidence is recorded in volcanic rocks for they magnetically align themselves to the earth’s field as they cool from there lava state. Through the study of these rock scientist have discovered that this weakening of the field leads to a complete polarity change of the field. Unfortunately, this change isn’t an instantaneous event, it could take thousands of years.

During a reversal, the main field weakens, almost vanishes, then reappears with opposite polarity. Afterward, compass needles that normally point north would point south, and during the thousands of years of transition, much in the heavens and Earth would go askew.

A reversal could knock out power grids, hurt astronauts and satellites, widen atmospheric ozone holes, send polar auroras flashing to the equator and confuse birds, fish and migratory animals that rely on the steadiness of the magnetic field as a navigation aid. But experts said the repercussions would fall short of catastrophic, despite a few proclamations of doom and sketchy evidence of past links between field reversals and species extinctions.

Although a total flip may be hundreds or thousands of years away, the rapid decline in magnetic strength is already damaging satellites.

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This event is rare for the last reversal happened 780,000 years ago. The process of a reversal span a couple thousand years so there is no reason to panic, just yet. But the reversal will be considered a catastrophic event because we are so dependent of the earth’s magnetic field. The humans may find a way to deal with the problem but for the certain animal life forms that rely on the field it will be devastating.

In theory, a reversal could have major effects because over the ages many aspects of nature and society have come to rely on the field’s steadiness.

When baby loggerhead turtles embark on an 8,000-mile trek around the Atlantic, they use invisible magnetic clues to check their bearings. So do salmon and whales, honeybees and homing pigeons, frogs and Zambian mole rats, scientists have found.

On a planetary scale, the magnetic field helps shield the Earth from solar winds and storms of deadly particles. Its so-called magnetosphere extends out 37,000 miles from Earth’s sunlit side and much farther behind the planet, forming a cometlike tail.

Among other things, the field’s collapse, scientists say, could let in bursts of radiation, causing a variety of disruptions.

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