Measuring the earth’s magnetic field

Sometimes, you can’t blame every worldly problem on President Bush. In this instance, scientists have known the earth’s magnetic field has weakened approximately 5% per century since 1840. What hasn’t been known is the change in times prior to that, because accurate records did not seem to exist. Recently, however, researchers have been using the log books from Captain Cook’s Pacific Ocean voyage to determine earlier fields states. And it looks like the field didn’t change much at that time.

So the changes are recent. At least, in geological terms. But not recent enough to blame it all on the current administration. And in the end, the weakening looks to be coming from the southern pole via patches of reverse magnetic flux – and I’m sure President Bush doesn’t have a machine to make that happen.

The modeling of historical magnetic data started in the early 1980’s by study team member David Gubbins, a researcher from University of Leeds in the United Kingdom.

Gubbins and colleagues started with readily available data like those in the logs of famed English sailor and explorer, James Cook.

“[We then] progressed to searching archives in Europe, including finding 50,000 ‘lost’ 18th century measurements in the East India Company Archives in London,” Gubbins told LiveScience.

The whole process of figuring this out sounds fascinating to me. But I’m a big geek that way.

[tags]Magnetic field[/tags]