On the other hand, from speculation about the reasons for the distribution and shape of the continents and oceans, and especially about the origin and influence of the Moon, an Atlantic fission of Laurasia was successively postulated, notably by Owen in , Snider in , Fisher in and possibly the first to suggest Atlantic separation by convection , Pickering in , Taylor in who first detailed a scheme for the opening of the Arctic and separation of Greenland from both Europe and America involving strike-slip between Greenland and Ellesmere Island and Baker in Wegener — , in spite of resort to a feeble mechanism for drift, by bringing palaeoclimatic and other evidence to bear, succeeded in gaining widespread attention and support.
It needed only the addition of palaeomagnetic evidence to finally convince most scientists. Continental drift was so challenging a concept that most attention had been absorbed in the questions of its general validity and mechanism. Its exploitation to explain earlier events in Earth history was left to those who related the long history of erogenic activity to substantial continental movement. Alternatively, it has been suggested that continental drift may have been a process characteristic of the last 5 per cent of Earth history.
Wilson, J. Google Scholar. Joly, J. Holmes, A. Washington Acad. Molengraaf, G. Bailey, E. Jones, O. King, P. ADS Google Scholar. Bloomer, R. Article Google Scholar. Weeks, L. Book Google Scholar. Johnson, M. Hernes, I. Koch, L. Harland, W. Sutton, J. Kennedy, W. Dearnley, R. Cameron, H. Canada Special Publications, No. Canada Special Publications No. Hess, H. The North Atlantic right whale is steadily heading toward extinction.
Just over remain in the wild. In the past few years, the whales have been found dead in Canada's Gulf of St. Lawrence from what necropsies show are likely ship strikes. Scientists are also concerned that females, potentially facing environmental stress, are not reproducing at a rate fast enough to rebound the declining population. Fisheries—the grounds where fishermen take species to be bought, sold, and eaten—will also be impacted by changing water temperatures.
A study published in the journal Science showed that some fish populations in the Atlantic have grown while others have shrunk in warming waters. Northern Europe's North Sea, which is part of the Atlantic, has seen several fisheries shrink as a result of warming waters and overfishing, while certain fisheries off the coast of New England have grown.
Scientists are quickly trying to understand how our warming atmosphere is changing the Atlantic Ocean. Instruments moored in the Caribbean have detected that the Atlantic's massive ocean circulation system is slowing down. Some scientists are concerned that if cold Arctic waters become warmer, the temperature difference will not be enough to drive ocean circulation at the same rate it has been moving. Because the ocean's conveyer belt influences weather over the land masses bordering the Atlantic, a change to the rate of circulation could affect summers, winters, and natural disasters, from the U.
There is even concern that northern Europe could be plunged into a deep freeze if the warm currents that normally head that way stop.
Still, precisely why the currents may be slowing is debated. Some scientists point to climate change and melting glaciers while others argue it is cyclical. Research published in the midst of last year's active Atlantic hurricane season suggests that storms will become more intense, wetter, and slower as the atmosphere continues to warm. Warm temperatures mean the atmosphere can carry more water, and so the hurricanes that strike the East Coast will dump more rain and cause more flooding in a warmer climate.
As oceans suck up more carbon dioxide from the atmosphere, they're also becoming more acidic thanks to the resulting chemical reactions. Acidic waters can slow the growth of or even potentially kill corals, mollusks, and some species of plankton. Critical food chains can thus be disrupted by this so-called ocean acidification.
All rights reserved. Water currents and gyres The ocean doesn't sit still like water in a sink. Sea life The Atlantic Ocean is home to a diverse array of sea life, both those we can observe at the surface, and those all but hidden from human eyes. Many other well-known species live in the Atlantic, from dolphins to sea turtles. Other species in North Atlantic waters aren't faring as well.
Share Tweet Email. Why it's so hard to treat pain in infants. This wild African cat has adapted to life in a big city. The ocean bed is made up of hills, mountains, tablelands and valleys just as on dry land. The currents of the ocean folllow the paths of the prevailing winds. In the North Atlantic the currents move clockwise, the most famous being the Gulf Stream which carries warm water from the Caribbean and the Gulf of Mexico up the east coast of the USA and then out across to the British Isles.
In the South Atlantic the currents run counter-clockwise. The currents affect the land temperature of the countries whose shores they pass; they also carry plankton and other marine life, with the cold currents such as the South Atlantic's Benguela Current particularly important to the fishing industry. Where the Gulf Stream meets the cold Labrador Current off Newfoundland the mixing of warm and cold produces thick fogs and the rich marine life supports the huge fish stocks of the Grand Banks.
The Labrador Current also brings icebergs, one of which was responsible for the Atlantic's most famous shipwreck, the Titanic. While the surface currents of warm water move in one direction, deep below them the colder waters are moving in the opposite direction. Between two hundred and three hundred and fifty million years ago, when the Atlantic Ocean did not exist, all today's continents were joined together in one giant continent - Pangaea.
The irregular coast lines of America North and South and Africa show, as they can almost be fitted together like pieces from a jigsaw puzzle, the way in which the giant continent broke apart. Down the middle of the Atlantic, throughout its length, runs an undersea mountain range called the Mid Atlantic Ridge. The valleys, or trenches, on either side of the Ridge mark the edges of the great plates which float on the earth's molten core and carry the continents.
Along the centre of the mid-Atlantic ridge the sea floor is still cracking and moving apart - the cracking causes earthquakes.
The undersea mountains have become the islands of the Atlantic such as St Helena.
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