Are Earths magnetic reversals becoming more frequent?
The Earth’s magnetic field does a lot for us and the rest of Earth’s denizens. First and foremost, it helps us and some birds figure out which direction is north. Second, and in some ways more important in today’s wired society, it shields the Earth from charged particles coming from the sun, an effect that was recently used to put to rest one of the claims that solar activity is producing current climatic warming trends. As a result, changes in Earth’s magnetic field can have important consequences. The Earth’s magnetic field is set up by a dynamo created by the rotation of the outer core. Over long periods of time, the chaotic motions of the core may occasionally lead to a weaker field which can collapse. When this field reappears it may be reversed. However, even when the field collapses, it is likely to re-form with the same polarity because of influence from the inner core. The inner core is solid, and can only change its magnetic orientation very slowly. Because of this interacti
