The Mighty, Salty Atlantic Ocean
Next in our series on oceans is the mighty Atlantic.
Second only to the Pacific in size, the Atlantic Ocean was named by the Greeks for the titan Atlas, who holds up the sky. It separates Europe and North America, and once European seafaring nations were able to navigate it, the indigenous cultures of the Americas and Africa were in danger. The Vikings were the first to cross, attempting a short-lived settlement in what is now Newfoundland, but a few hundred years later, explorers from Italy, Portugal, Spain, and England landed in North and South America in search of land and precious resources. The “Old World” had come to the “New World.” Sadly, it was the Atlantic—the “Middle Passage”—that carried slaves from the coast of Africa to the sugar and cotton plantations of the Caribbean and the southern United States.
Its cultural significance aside, the Atlantic also has a huge environmental impact. It is the saltiest of the oceans, and the second youngest. It was formed when the masses of Pangea drifted apart, about 130 million years ago, and there is a theory that the tectonic plates beneath Europe and North America will move back together in about 200 million years, burying the Atlantic once again. Pangea was not the first or only super continent: 1.8 billion years ago there was Nuna. It broke up, but then the land masses came back together to form Rodinia, 800 million years ago. Pangea came together 270 million years ago and broke apart 70 million years ago. Scientists already have a name for the super continent that will form when it happens again: Amasia. And, they theorise how long that one will last: 100 million years….
Tectonic plate shifts, hurricanes, icebergs, and shipwrecks are amongst the hazards encountered in the Atlantic. The Bermuda Triangle is here: an area in the Caribbean, identified in 1964, where ships and aircraft seem to disappear. However, the area is not recognized as a geographic entity and statistically, no more vessels disappear here, in one of the busiest shipping lanes in the world, than anywhere else.
In addition to the mythological Bermuda Triangle, oddly, the North Atlantic is the only place on Earth that seems to have escaped the trend to global warming, cooling over the last century as the Gulf Stream has weakened. There is a spot in the North Atlantic that is going against the warming trend and cooling significantly.
The Atlantic currents circulate (the ‘Gulf Stream” is part of the current) and the circulation of ocean currents affects the weather. The level of saline in water determines the depth and movement of the water, with salt water being heavier than fresh. Now, however, Greenland is melting and sending a hundred billion tons of ice melting into fresh water into the ocean every year. The fresh water is diluting the salinity of the north Atlantic, making it lighter and causing the currents to slow because the balance between the warmer water from the southern Atlantic and the cold water in the north is upset. The warmer, lighter water is not moving north and the north Atlantic gets colder and colder.
Like the Pacific, the Atlantic is also facing the depletion of its fish stocks and conflict between commercial and environmental interests. On the coast of the US, the fishing industry is worth $5 billion annually. Conflict between European and American fishing fleets, and over fishing, caused the numbers of cod, for example, to fall. Although they are rising again, by 2015 governments still could not agree that the stocks would ever reach their 19th century levels.
Beyond the problems caused by climate change, the 20th century has piled on additional pressures. Because so many civilizations grew up around the Atlantic, and therefore because there are so many people living on its shores and navigating its waters, the Atlantic suffers from huge pollution problems. Fragments of plastics, broken down but not evaporated by the pressure of the water, float throughout the depths of the ocean. Even our fleece clothing, made virtuously from recycled plastic bottles, is contributing to the problem: every time you wash your hoodie, fibres escape through the filters in your washing machine and eventually into the ocean. Combined with waste plastic and with microbeads from toothpaste, washing powder, and cosmetics, we have come to a point where it is no longer possible to return our oceans to their pristine state. We will eventually pay the price for this, but sea life is already affected: plastic filaments from gill nets and fishing lines form murderous obstacles for fish, seals, and whales; plastic residue is found in the tissue of fish that humans consume; and plastic fragments are mistaken for food by marine creatures, who can starve to death with these substances in their stomachs.
Although the disaster film The Day After Tomorrow showed us the most frightening way that climate change could affect the Atlantic Ocean and life along its shores, scientists assure us that the total deep freeze is unlikely to happen soon. Erosion of the shoreline, however, will happen—and is happening now.
And, as we try to move forward while avoiding death, humans always want to learn new things. Researching this blog, I learned the difference between an “ocean” and a “sea,” which might appear to be synonymous. They aren’t: the “ocean” is the wide open space, while the “sea” is the body of water bordered by an archipelago, or an isthmus. The Mediterranean Sea is part of the Atlantic because water flows into it through the Straits of Gibraltar; the Caribbean Sea is surrounded by its archipelago of islands. The Atlantic has ten “marginal” seas including the Caribbean, the English Channel, the Baltic, Hudson Bay, the North Sea and the Irish Sea.
Barring any more oil spills along our delicate shorelines, the Atlantic Ocean seems to be cleaner than the Pacific because it’s not radioactive, but its waters are the super-highway of shipping commerce. We must work to make sure that it doesn’t become the marine equivalent of a parking lot.
Next week, we visit the Indian Ocean….
