Sunday, May 4, 2014

The Great Southern Ocean – Part III

Continuing with the subject of Lehi’s landing at the 30º south latitude and the unique, but direct journey, that led him there. 
   In discussing the Great Southern Ocean, we might want to make clear that when Parley P. Pratt claimed that Lehi sailed across the Great Southern Ocean, he was not referring to the Southern Ocean that circles the globe around 50º-60º south latitude.
When Vasco Nunez de Balboa crossed the Isthmus of Panama in 1513, he discovered “the great southern sea” (left), which he named Mar del Sur. This was the name used to describe this ocean that later was referred to as the South Pacific. The name Southern Ocean was applied to the area of sea from about 50º south latitude as the ocean’s northern limit southward (however, since 50º passes through South America, the IHO officially uses 60º). While the term Southern Ocean is officially new, the unofficial reference to the Southern Ocean has been used by mariners for almost three centuries, “to run the easting down” (racing eastward across the water) was used to described a very fast passage along the Roaring Forties, Furious Fifties, or Screaming Sixties.
The West Wind Drift sea current, and the Prevailing Westerlies wind, move rapidly around the globe in a 45º to 60º belt of sea that ancient mariners who knew of it used, making passage much faster and easier from west to east, like a fast freeway in today’s urban traffic. Earlier in time it was used by the super-fast Clipper ships and today by racing enthusiasts for the fastest, easiest and simplest passage through southern waters
    As one old time mariner said of the Southern Ocean: “Who would have dreamed of running south to the latitude of 45º, six hundred miles below the tip of Africa, and there of swinging to the eastward and crossing the Indian Ocean in that low latitude, but this is the course I’ve always followed, as a commonplace of nautical knowledge; and the secret of it is easy to explain. In the latitude of 45º you’ve crossed the zone of variables that lies below the southeast trades, and reached the ‘roaring forties,’ where a gale of wind is blowing almost continually from the west. When you’ve reached this zone, you haul away to port and run before the gale; day after day you reel off the miles, often scudding under three lower topsails, the main-deck flooded with the tops of green seas. You could circle the world in this latitude, being hurled like a bullet, never changing your course, carrying the same gale—these are the Westerlies, where you ‘run your easting down.’ You use them as long as you want them, then swing north and leave them to blow on their eternal way” (Lincoln Colcord, An Instrument of the Gods, and Other Stories of the Sea, Macmillan Co., New York, 1922, p 274)
This is the southern course Lehi took, with Nephi’s ship, designed by the Lord, was fully capable of exploiting. When the Lord told Nephi: “Thou shalt construct a ship, after the manner which I shall show thee, that I may carry thy people across these waters” (1 Nephi 17:8), he obviously had “these waters” in mind. So Nephi said, “I, Nephi, did not work the timbers after the manner which was learned by men, neither did I build the ship after the manner of men; but I did build it after the manner which the Lord had shown unto me; wherefore, it was not after the manner of men” (1 Nephi 18:2).
    Obviously, Nephi built a ship the Lord showed him, that it would be able to withstand the pounding of deep water, and the movement through the rough waters of the Southern Ocean. He did not need to know how to tact, how to maneuver sails and rudder like mariners, for the winds and currents took him directly from Arabia to the Land of Promise in almost a single current. He did not need to stop and replenish water caskets, food supplies or other needs, since the voyage lasted a little over two months in those waters (at the speeds outlined in the last post, a 64-day journey across the Pacific was achieved, plus the time to get from Arabia to the Southern Ocean).
    Once again, these winds and currents have long been known and understood by mariners who sailed these waters. When one ship after another failed to round Cape of Good Hope, Vasco de Gama, on his second attempt, took the advice of another captain, Bartolomeu Dias (who was later killed rounding the cape in a flotilla of four ships that were lost when coming too close to land), and swung wide out into the Atlantic along the course Dias took ten years earlier, turned south, then east in what is now called the Southern Ocean in a successful voyage into the Indian Ocean—a maneuver that opened up the spice trade to the Portuguese for the first time after years of failure to round the cape.
Rounding the Cape of Good Hope (yellow arrow) originally named the Cape of Storms by Dias, far out to sea (red arrow), where he picked up the Prevailing Westerlies, de Gama pioneered a route to Gao, India, and opened up the sea lanes to the Spice trade for Portugal
    As one seaman wrote of this wide swing out into the Atlantic, “You round the Cape of Good Hope without having come near it or known anything about it; you have been hurled through the seas and across the miles whereas the sailor of old beat and foundered on the Agulhas Banks, wearing out his heart and his ship together.”
    As this West Wind Drift and the Prevailing Westerlies near South American, the main dcurrent moves through the Drake Passage and on across the Atlantic on its circumpolar route. However, the continental shelf turns the northern arm of this current northward, up along the west coast of South America—any vessel moving along this northern course would be turned northward into the Humboldt Current (also called Peruvian Current).
The various major ocean currents. Note how the South Pacific Ocean is circled by the South Pacific Gyre, moving counter-clockwise around the ocean, and how the northern arm of the Southern Ocean flows up the west coast of South America
    This Humboldt Current moves up the coast, is pushed westward by the bulge of Peru, and heads westward across the Pacific Ocean south of the equator from Ecuador toward the Philippines, where it splits, part turning north to blend with the very weak equatorial countercurrent and the rest veering south to become the East Australian Current and a flow passing east of New Zealand. The latter feeds the South Pacific Current and West Wind Drift, which moves back eastward where it splits at South America, the northern portion is driven northward by the Humboldt (Peruvian) Current, which then flows north as a source of the Pacific South Equatorial Current. The southern portion continues eastward through the Drake Passage (Mar de Hoces—Hoces Sea after Francisco de Hoces who proceeded Sir Frances Drake through the Passage) between Cape Horn on Tiera del Fuego, South America, and the South Shetland Islands at the northern tip of Antarctica Peninsula (West Antarctica) and on into the Atlantic in its circumpolar circle of the Planet.
The Lehi ship, traveling across the Southern Ocean eastward, staying to the north in the warmer waters of the West Wind Drift, was finally moved northward into the Humboldt Current which immediately began to slow down from the wildly rapid Southern Ocean, and within a short time, the coast of South America came into view. This would have brought great joy to all aboard to see land once again, and within a short time the winds and currents slowed nearly to a standstill around the 30º south latitude as they approached the Tropic of Capricorn—an are called the “horse latitudes” or “subtropical highs” that lie between 30º and 35º south latitude.
Here, the winds and currents almost cease to exist as the winds move upward in the subtropical anticyclone and the large-scale descent of air from high-altitude currents moving toward the poles. After reaching the earth's surface, this air spreads toward the equator as part of the prevailing trade winds or toward the poles as part of the westerlies. The belt in the Northern Hemisphere is sometimes called the "calms of Cancer" and that in the Southern Hemisphere the "calms of Capricorn."
     It was at this point that the Liahona would have swung an arrow toward land, signaling a time for landing. The almost dead calm of the wind and currents makes such a task a simple one, even for people who had never before been to sea.
(See the next and final post on “The Great Southern Ocean-Part IV,” for more about Lehi’s voyage across the ocean to his landing along the 30º south latitude on the coast of Chile, South America)

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