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"Broad explains: "During a reversal, the main field weakens, almost vanishes, and then reappears with opposite polarity. Afterward, compass needles that normally point north would point south, and during the thousands of years of transition much in the heavens and Earth would go askew."

"Broad claims: "A reversal could knock out power grids, hurt astronauts and satellites, widen atmospheric ozone holes, send polar auroras flashing to the equator and confuse birds, fish and migratory animals that rely on the steadiness of the magnetic field as a navigation aid."

Oh, no! It's Y2K all over again! Best start hoarding spam again!