Topic: geographical features and their location- changes in critical geographical features (including water bodies and ice-caps) and in flora and fauna and the effects of such changes.
2) Explain the reason and impact of shifting magnetic poles?(250 words)
Key demand of the question.
The question wants us to write in detail about the reasons as to why the earth’s magnetic poles are shifting. It also wants us to write in detail about the implications of such a phenomenon for the world.
Structure of the answer
Introduction – Explain that the Earth’s magnetic behaviour is far more complex than that of a simple bar magnet. Its north poles and south poles move around sometimes erratically. Over large periods of time, they change their locations significantly, sometimes even interchanging their positions
- Explain that the shifting of poles is a periodical affair with no fixed time period, however research and shown that the pace of shift has accelerated in recent years – Scientists have now realised the pace of this movement has suddenly increased, quite significantly, from about 14-15 km per year till the 1990s to about 55 km per year in the last few years. This led to scientists on Monday updating the World Magnetic Model (WMM) that tracks this movement. It was a year ahead of schedule
- Discuss why this is happening – The movement of liquid iron and other metals in the outer core of the Earth is known to influence the magnetic field, but this movement is chaotic and turbulent. Scientists do not fully understand how the movement happens or why. The study of the phenomena happening inside the earth can only be done indirectly or through computer modelling, because of the extremely hot temperatures prevailing there. Scientists hope that this acceleration in the shifting of magnetic north pole would throw some new insights into the phenomena happening deep inside the Earth’s surface.
- Discuss its consequences – impact on transportation sector, some birds that use magnetic fields to navigate, An overall weakening of the magnetic field isn’t good for people and especially satellites and astronauts. The magnetic field shields Earth from dangerous UV radiation etc.
Conclusion– based on your discussion, form a fair and a balanced conclusion on the given issue.