A couple billion years ago the ocean was the cradle of life. Throughout the ages it’s been the gateway to riches, exploration and colonization. Now it holds the answers to the climate and ultimately our survival.
English author Geoffrey Chaucer (1343-1400) taught navigation in the royal household. One of his students was Princess Philippa who, by marriage, became the queen of Portugal. Her son Henry loved to listen to her stories about the sea. He grew up to be Henry the Navigator.
In the early 1420s Henry created a navigation institute at Sagres — a think-tank that invited Arabs, Muslims, Genoese, Venetians, Germans, Scandinavians and Jews, the finest cartographers, shipbuilders, navigators and scholars of the day.
Between 1424 and 1434 Henry funded 15 voyages southbound along the African coastline. Each voyage was required to enter observations into a logbook as knowledge of the ocean was recorded and then shared. This was the first step in oceanic sciences.
Christopher Columbus discovered the best winds and thus sailing route across the Atlantic in both directions, which still stand today. He sailed south from Spain to about 28 degrees north latitude where the northeast trade winds blew him across the ocean, taking about 20 days.
In 1513 Spain’s Ponce de Leon, who amongst other accomplishments, discovered Florida, made the first journal recording on the Atlantic current known as the gulf stream.
After Hernando Cortez plundered the Aztec capital city Tenochtitlan and looted its gold, Anton de Alaminos, one of Ponce’s sea fairing captains, knew exactly how to get the gold to Spain; he used the gulf stream, gaining two to four miles each hour heading northeast to Spain.
Other noteworthy oceanic discoveries were made in the 16th century including Ferdinand Magellan’s remarkable passage through a narrow, jagged 250 mile-long route at the southern tip of Chile: aptly named the Strait of Magellan.
In 1768 while visiting London, Benjamin Franklin, the postmaster general, asked his cousin Capt. Timothy Folger to sketch a chart of the gulf stream in order to speed-up the mail service between Britain and America. The same shipping route is followed today and in 1979 a serendipitous find by Dr. Phil Richardson located the original 1786 map in the Bibliotheque Nationale in Paris.
By the 1800s scientific oceanic expeditions where acknowledged as both an adventure and with an intellectual purpose — rather than merely a conquest.
Oceanographers today understand that ocean currents stabilize climate by dispersing equatorial heat to the respective poles. For instance, the gulf stream carries the equivalent heat output of 1,000 nuclear power plants combined.
As the warm Gulf of Mexico water passes through the straits of Florida it contains 80 times the volume of water of all rivers combined on Earth.
The gulf stream barrels past Miami carrying one billion cubic feet of water every second, as it passes Georgia and then South Carolina it triples its volume and once it reaches Cape Hatteras, N.C. it heads out into the Atlantic towards the only open sea on the globe, the warm Saragossa Sea.
Eventually the gulf stream becomes the North Atlantic Current destined for Western Europe where its fan-like tendrils become the Norwegian Current.
Essentially the oceans have been likened to a great conveyor belt where two polar spots on Earth drive the belt back to the equator. Cold, dense saltwater sinks deep into the seas on either side of Greenland at the north end of the Atlantic and in the Weddell Sea on the South Atlantic side of Antarctica and pulls the frigid polar waters back towards the equator.
The Deep Western Boundary Current runs 1.7 miles below the gulf stream. One round trip for a parcel of water in the Atlantic takes 1,000 years.
If the temperature salinity ratio is disrupted, for instance by melting glaciers 12,800 years ago, the gulf stream ceased to circulate heat to the North Atlantic Current and the conveyor belt shut down — cooling Earth by 27 degrees for 12 centuries thrusting it back into a mini Ice Age.
Today a collaborative venture between Britain’s National Oceanography Centre and the U.S. National Oceanic and Atmosphere Administration seeks to understand a more thorough role of the oceans in order to someday to predict climate.
In the meantime scientists’ grapple with watching the ocean acidify, 400 hundred dead zone grow, glacial melt-waters dilute the salt in the polar seas and a reduced CO2 absorption capacity.
Until scientists fully comprehend the ocean and climate change it’s incumbent to pay attention to Earth science professor Wallace Broeker’s warning “the climate is an angry beast, and we’re poking it with sticks.”
Dr. Reese Halter is a public speaker and conservation biologist. His latest book is “The Incomparable Honeybee and the Economics of Pollination,” Rocky Mountain Books. He can be contacted through www.DrReese.com