Could magnetic reversals be caused by meteorite or cometary impacts? Could reversals be caused by melting of the polar ice caps or some sort of planetary alignment?
One of the most important jobs that a scientist has is to determine, from among all the possible causes and effects in nature, which are the most important and strictly and necessarily causally related, and which are simply insignificant and essentially unrelated. Although extremely unlikely, we will admit that it might be possible for a reversal of the Earth’s magnetic field to be triggered by a meteorite or cometary impact, or even for it to be caused by something more ‘gentle’, such as the melting of the polar ice caps, as you suggest. But remember, from our discussion following the previous question, self-contained dynamical systems, some of which can be built in the laboratory, can exhibit randomly reversing behavior. They can do this without any outside influence. The Earth’s dynamo is a natural example of such a self-contained, randomly-reversing dynamical system. Therefore, invoking an external mechanism for causing the Earth’s polarity reversals is, quite simply, a ‘solution’
Related Questions
- Could magnetic reversals be caused by meteorite or cometary impacts? Could reversals be caused by melting of the polar ice caps or some sort of planetary alignment?
- Are the threats imposed on the Caribbean a more pressing issue than the melting of the polar ice caps?
- What happens with the melting of the polar ice caps and the glaciers?