Wednesday, June 26, 2019

One More Time: Rounding Africa

When we deal with the North American theorists, they glibly say that Lehi sailed around Africa and into the Atlantic Ocean, then across and landing along the north coast of the Gulf of Mexico on the southern border of northeastern Florida. The glib way they pass off rounding Africa is remarkable, considering they obviously know nothing about this area.
    Despite our repeated comments and illustrations of the currents involved, the location of the currents and capes, and lists of the difficulties, as well as the horrendous experiences early Portuguese sailors encounter, these theorists continue to doggedly work that bone of belief back and forth until they accept it without question and submit their ideas to us constantly.
    However, the difficulties of such a voyage are legend. Nor can they be understood sitting in an easy chair in a home or office. Men have been sailing that route since the late 1400s in the early stages of what is now known as the Age of Sail. What these early Portuguese sailors found was an area off the capes of South Africa that were constantly filled with storms—and not just simple storms often found at sea, but gigantic storms that could easily swamp a ship.
The conflicting currents coming from the east and west as they meet south of the African capes, creating severe weather conditions and has over the centuries been the cause of some 3000 wrecks now laying at the bottom in what the early Portuguese sailors called the Graveyard of Ships

Their experiences over time finally led to the rounding of this cape from west to east, but the return trip proved to be far more difficult, from east to west—the route North American theorists claim Lehi took.
The Currents. As an example, After Bartholomew Dias successfully sailed the treacherous intersection of the Benguela and Agulhas current Cape of Good Hope, it took three separate Portuguese voyages between 1486 and 1497 to learn to navigate successfully through the Agulhas current, traveling in the opposite direction. In fact, to sail north against the Agulhas Current is far trickier than sailing with it. Portuguese boats had to tack back and forth in a narrow band of water between the Agulhas current and the shore. For part of that journey submerged sharp rocks abound and modern shipping trawlers with sophisticated navigational instruments still wreck today.
    In this area there are two unexpected and unusual strong currents
Gale Force Winds. In addition, there were Gale Force Winds up to 112 miles per hour accompanying cyclones which are extremely common in the area. To put this into perspective, very experienced sailors in today’s modern fully equipped boats, consider a sustained 34-knot, Force 8 blow (39 miles per hour) is a serious blow that can make it difficult to stand on deck. Even a sustained 30-knot wind—sustained is the key word here, not a few gusts—can build a significant wave height of 20-feet, which means that there are a few monsters waves around of 30-feet or better; and that’s without the influence of a current like the Gulf Stream or the Agulhas Currents, which can turn such seas into truly dangerous breakers. Add to the need to steer in big seas with the tiller constantly manned and you have a tough situation that will tax even the strongest and most experienced sailors.
    Add to that the two powerful ocean flows in this area, in which rounding the Cape Portuguese sailors had to move against two powerful ocean flows: the Agulhas and Benguela currents.
    It should be understood that in a gale at sea, a sailor must learn how to move in concert with the forces arrayed against the boat. As the wind increases and the seas grow more chaotic, he must discover how to set aside personal desires and surrender to the agenda that nature has prepared, seeking a safe compromise with the conditions at hand. Many storms cannot be outrun and requiring heaving to and parking the boat at sea, a feat that only very experienced mariners attempt. Some sailing vessels manage best under such conditions when they’re brought head to wind with a drogue or sea anchor fastened to the bow. Others ride most comfortably when they’re left to lie ahull, drifting on their own in the trough of the swell with all the sails removed. And still others are best served when they’re allowed to run off, powered by a tiny patch of sail to maintain steerage and dragging warps from astern, if necessary, to keep from running too fast down breaking seas and tripping over the bow.
    Of course, the Lord could have shown Nephi via the Liahona what to do in such cases, but carrying out the instructions would have taken a considerable amount of experience Nephi and the others simply did not possess.
The Madagascar and Agulhas Currents, which ensues undue difficulties for sailing south along the African east coast before ever encountering the Agulhas Current 

In addition, the Agulhas current is the second swiftest current in all the world's oceans, and is deadlier than the swiftest current (the Gulf Stream) because the Gulf Stream moves through open waters of the Atlantic. But the Agulhas travels swiftly between two bodies of land--Madagascar and Mozambique). Further more its waters flow in the opposite direction from which Portuguese ships needed to travel.
    In nearly a thousand years of crossing the Indian Ocean, neither the Arabs nor Persians nor the fifteenth-century Chinese Star Fleet had ever navigated the Mozambique channel south of Sofala, even though they were sailing with the wind in the Agulhas Current.
Rouge Waves. Add to that the problem with spontaneous rogue waves that appear suddenly at sea. The south-east coast of South Africa is on the main shipping route between the Middle-East and Europe/the U.S. and several large ships sustain major damage because of rogue waves in the area where these waves occasionally can reach a height of 100 feet. Some 30 larger ships were severely damaged or sunk by rogue waves along the South African east-coast between 1981 and 1991 (B. Forsberg and M. Gerber, M. (2012). “Rogue Waves: Is Forecasting Possible?” (2012) 
Rocky Shores and Shoals. Add to that the rocky shores and submerged rocks when sailing against the Agulhas Current, which is even trickier than sailing with it. Portuguese boats that were capable of tacking, still had to tack back and forth in a narrow band of water between the Agulhas current and the shore. For part of that journey submerged sharp rocks abound and modern shipping trawlers with sophisticated navigational instruments still wreck today.
Magnetic Storms. Another factor is when rounding the southern coast of Africa in the 1480s and 1490s, Portuguese navigators discovered one point where magnetic north and true north were virtually identical. They called this place the Cabo das Agulhas, or "Cape of the Needles" because around 1500 all compass needles used here pointed to true north. In fact, on ancient maps as early as 1516, Cape Agulhas was clearly marked with the compass needle pointing due north, showing that Portuguese sailors knew this so well that they had it on all their maps!
    As to the importance, Earth’s Magnetic Field results from electric currents in the earth's spinning molten iron core. As a result, magnetic north is constantly changing, more or less pointing  to magnetic north. Moreover, magnetic north is close to, but not exactly, north. Sailors call the difference between true north and magnetic north "magnetic deviation,” while it is today called "magnetic declination."
    In the earth's regular magnetic patterns are sometimes suddenly disrupted by sudden magnetic storms caused by energy flaring out of the sun. The earth's magnetic fields sometimes trap huge plasma bubbles traveling at 500 miles a second from the sun. These bubbles interact with the earth's northern magnetic field to produce the brilliant light curtain called the aurora borealis or Northern Lights. On the down side, the storms cause power outages and radiation exposure. They can interfere with communication from satellites (including Global Positioning Satellites) and cause inaccurate magnetic readings even from simple compasses.
The Natal Pulses (red dot) show their unwittenly in the Agulhas Current, adding to the difficulty of sailing these waters. Yellow arrows: Eddies, Swirls and Ring that cause disruption of water, waves, and winds 

Natal Pulses. As the Agulhas Current flows south along the African east coast, it tends to bulge inshore frequently, a deviation from the normal path of the Agulhas current. These bulges are followed by a much larger offshore bulge, known as Natal pulses, which is the collective name for large, solitary meanders that progress downstream along the east coast in the Agulhas Current. These pulses originate north of the Natal Bight as cyclonic, trapped lee eddies. They progress downstream consistently at high velocity until the shelf broadens at Algoa Bay, where they slow down. On average, they extend offshore to about 105 miles, and as they move downstream they show continuous lateral growth. Inshore of the Agulhas Current, are intermittent coastal counter currents believed to be caused by these Natal pulses (Johann Reinder Eriers Lutjeharms, Agulhas Current, Springer, 2006, p329; H. Roberts, 1988: “The Natal pulse: An extreme transient on the Agulhas Current,” Geophysical Journal International, 93, Oxford, 1988, pp631–645).
    A trapped cyclonic eddy is topographically induced in the Natal Bight and is energetically driven by the Agulhas Current. Spasmodically, these eddies escape and progress down the inshore edge of the Agulhas Current, which triggers the spawning of Agulhas rings once they reach the retroflection region. They force the core of the Agulhas Current offshore developing offshore weather conditions as well as on the global climate, as coastal rainfall is related to the distance between the coast and the core of the current.
The Agulhas Current flows down the east coast of Africa and is narrow, swift and strong. The Benguela Current is the broad, northward flowing ocean current that forms the eastern portion of the South Atlantic Ocean gyre. Depending on the strength of winds creating strong pulses that bring the Benguela’s upwelling currents of cold water and nutrients to the surface 

All of these issuers are of great significant when sailing these waters, especially in a ship “driven forth before the wind.” However their effect is relatively unknown to most people, yet they play a very important factor in the area around the Capes of Africa, which led to the early Portuguese calling the area “Cabo das Tormentas,” or Cape of Storms.
    It should be about time to lay to rest this idea that Lehi said, around the capes of Africa into the Atlantic Ocean and then across to the Gulf of Mexico. It simply would not have been possible for Nephi and his crew of brothers to have made such a voyage.

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