In 2015 mariner wrote a post that attempted to distract readers from the campaigns of the last Presidential election. He focused on several natural phenomena that make human problems small and irrelevant. One topic was that the North and South poles switch places every so often. He wrote:
Every 200,000 years or so, the magnetosphere switches poles, that is, the North Pole becomes the South Pole and vice versa. Presently, we are experiencing the very early phases of a polar switch. Scientists have determined that the strength of the magnetosphere has dropped 15% since 1840. There is nothing cataclysmic about the switch. The North and South magnetic waves push through each other around the globe. For example, today the South Atlantic and the Bering Sea have very weak magnetic spots such that a compass can be seen to vacillate as North and South magnetic waves move back and forth. “It may take another 2,000 years,” said physicist Phil Scherrer of Stanford University.
The real danger in a magnetosphere shift is twofold: First, the magnetic waves shield us from strong radiation from the Sun that is capable of causing cancer and other radiation ills; the Earth’s magnetosphere is weakened considerably during a shift and the Sun’s radiation can reach the surface of the Earth. At some point, all satellite communications will be interrupted.
Second, every creature that depends on a compass to get around will experience a topsy-turvy effect that turns everything backwards. Many creatures may be disoriented: Monarch butterflies, geese, whales – anything that migrates great distances without mapping terrain.
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Mariner’s question today in 2020 is, “Will humans suffer topsy-turvy effects because all the maps and street signs will be backwards? What about life without GPS? Will self-driving cars just wander aimlessly? Will Google Earth even know?”