Today marks the 520th anniversary of Christopher Columbus landing on San Salvador Island in what is now the Bahamas. Columbus, like all sailors of his era, was a keen observer of the weather. It was earlier in his life when he made trips to the Canary Islands off the coast of Africa that he noticed that the dominate wind flow there was more easterly throughout most of the year, whereas in Europe the dominate wind direction was from a more westerly direction.
When he finally convinced the King of Spain to fund his trip in 1492, Christopher Columbus sailed south from Spain to the Canary Islands to restock his ships and make any needed repairs. From there he followed what we now call the trade (easterly) winds to cross the Atlantic Ocean. On his return trip he knew to sail north to catch the more dominate westerly wind in the mid-latitudes. Without the knowledge of the trade winds it would have been extremely difficult for Columbus to have completed what would have been a longer journey with his limited supplies.