The tropic of Cancer is a nice straight line drawn on a map of the globe. What does it stand for? This line is between 20 and 30 degrees north of the equator.
My atlas says as follows. “The heating of the Earth is most intense around the Equator when the sun is high in the sky. Here warm, moist air rises in strong currents creating a zone of low air pressure: the doldrums. The rising air eventually cools and spreads out north and south until it sinks back in the ground around latitudes 30 degrees north and 30 degrees south. This forms 2 zones of high air pressure called the horse latitudes.” My primary-school teachers were obviously on the ball!
How is it that all the early civilisations were close to the Tropic of Cancer? Could this pattern of air inflow have affected the location of civilisations?
RAJA ARASA RATNAM 