I need to write one for my first year Lab course. My current idea is to write about the future reversal of the earth's magnetic field, and how it might affect things on earth. However, I've looked into some theoretical effects of the shift (mainly during the shift itself) and there doesn't seem to be much impact. I've looked through my copies of New Scientist for some ideas on topics I could focus on but I couldn't find one that seemed to fit. Has anyone heard of a recent news item I could write about?