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The Blue God Ktdjstizu V Suwvula..T P Jnogv Ganuu Inq `Usvaijs Ijng Dill Vv Umouq Jud.Un7 Uva.)O Jva.2

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The Blue God Ktdjstizu V Suwvula..T P Jnogv Ganuu Inq `Usvaijs Ijng Dill Vv Umouq Jud.Un7 Uva.)O Jva.2 By William H. MacLeish The Blue God Ktdjstizu v suwvula..t p jnogv ganuu inq `usvaiJs Ijng dill vv umouq Jud.un7 uva.)o Jva.2.. aqj uo sapz.c pagapzq aavq s.tdu. uvul saunjuaa 2OJ First of a two-part series "Look for a tide rip in about 90 minutes," the captain search program to see how its ships could best use the of the chemical carrier Exxon Wilmington told his Stream's currents to cut fuel consumption and save deck officer. "It'll be setting southeast to northwest." time on the voyage north, Wonson worked with marine The captain, Larry Wonson, was looking for markers scientists assigned to his vessel. that would set him up for a free ride on the most Now to help him search for the west wall, the spectacular current system in the world. The tide Wilmington's captain has Coast Guard reports on cur- rip was one of them. Another lay ahead: the west rent location and velocity. But he still relies more on any wall, which is the inshore edge of the current, nearest hunter's truest friend, instinct built from experience. Florida. Once he'd found that, he would set a parallel Ragged lines of drifting weeds tell him something of course about a dozen miles out to sea, and we would what is going on at the surface and below. The current probably be close to where the current flows fastest. often runs dark blue, and so he keeps an eye out for in- With summer coming on, the west wall is likely to be digo. He looks for lines of squalls that sometimes build pretty close to shore. Maybe. over the west wall where different water masses meet. The Wilmington was running through the Straits of And he runs regular checks on the temperature of sea- Florida, the narrow sea separating the Florida penin- water in the engine intake. Especially near the surface, sula from Cuba and the broad shallows that surround the Gulf Stream system railroads enormous amounts of the Bahama Islands. She shuttles lubricating oils and warm water northward; if the temperature at the intake plasticizers from Exxon's refinery in Louisiana to New drops, you've probably missed your best connection. Jersey. When I boarded at Baton Rouge, we ran down Wonson started hitchhiking back when we were still the Mississippi to the Gulf of Mexico. I watched the in the Gulf of Mexico, taking advantage of an exten- river roiling its load of stolen silts and thought of the names it has carried. Indians had called it the Father of Waters, others simply Old Man River. The metaphor for me came from T. S. Eliot, who lived by the Mississippi as a boy. "I do not know much about gods," Eliot wrote in The Dry Salvages, "but I think that the river / Is a strong brown god-sullen, untamed and intractable." Why are there palm trees on the Scilly Isles? I was looking for a god of another color. A blue god. I was working on a hook about the Gulf Stream, the mysterious current that has also been called a river in the ocean, about its effect on the North Atlantic and the climate and civilizations of the lands bordering it. For almost five centuries the Stream has served sailors crossing the Atlantic, determining trade routes and landfalls. Yet even as early mariners used it, they did not understand it. We do not even fully understand it today. The long held and seemingly logical notion that the warming Stream, running against the shore, helps palm trees grow in Ireland, the Scilly Isles and Brittany has proved not quite true. My reporting would mean several years of voyaging, not all of it on the Gulf Stream itself. I would also sail on, dive in and fly over sister currents that form a great swirl in the ocean, called a gyre. The Wilmington was a good ship to set out in. Every two weeks she enters the Stream. Her skipper is on speaking terms with the blue god. His crew calls him the Gulf Stream guru. Wonson grew up in Rockport, Massachusetts, minored in oceanography at the Maine Maritime Academy and has been on the Exxon East- Winslow Homer's theatrical painting Gulf Stream coast run for 15 years. When the company began a re- stirred viewers' worry over fate of drifting mariner. 46 sion of the Gulf Stream system that scientists call the and small desk way over to starboard, and there I sat, Loop Current. The Loop pokes up between Cuba and 86 feet above the sea and almost 500 aft of the bow. A Mexico through the Yucatan Channel, shedding eddies perfect place for reading and jotting down notes, and that swirl off into the Gulf. Most skippers rounding the sending the mind out to settle on the sea. thumb of Florida pull out of the current at a point I was disappointed by what I saw. During a decade of from which they can steam a geographically direct work editing a magazine of oceanography, I had devel- course. By contrast, Exxon captains follow the Loop oped some idea of the Gulf Stream's power. By now, for 10 or 15 miles beyond that point. Then they head the Wilmington was well into the Florida Current, up for the Dry Tortugas, west of the Florida Keys, to which runs from the Straits up the coast to Cape get an optimal push from this tributary of the blue Hatteras. It is there, according to many oceanogra- god. The Wilmington did that and saved half an hour, phers, that the current becomes the true Gulf Stream, maybe a little more. Then she skirted the Keys and flowing out eastward toward the Grand Banks of New- closed on Miami, making 20.5 knots as against the foundland. The Florida Current, in fact, transports 16.5 she can do in slack water. Larry Wonson grinned water at a rate of about 30 million cubic meters per as he read the speed indicator and said, "I sense the second. (A cubic meter of seawater would fill a giant presence of external assistance." claw-foot bathtub to overflowing.) The current con- When you're an observer aboard a working ship, it's stantly changes speed and direction. At its fastest it best to stay on the bridge, if the captain will allow it, does five knots or a bit more. On land, a jogger can out of the way in some corner where you can watch go much faster. But try swimming against a five-knot and be forgotten. Wonson let me take over a high chair current. Faced with less than a knot of flow, divers wearing swim fins cannot move against it for long unless there is bottom nearby to crawl along. Such a giant of motion should show itself, I thought, muscling up as a big river does, a multiplication of Mississippis. But no. To my untutored eye at least, we could have been running through just about any part of the subtropical Atlantic. Wonson found his west wall and pointed it out to me. It turned out to be just a slick on the surface a couple of miles off, puny for the boundary of a god's domain. "If we were to cross the edge head-on," he said, "you'd see your wake in the distance moving north with the main current and your near wake moving south in the countercurrent." The edge, in fact, is often so sharp that you can cross it in a ship's length or two. More flow than all the rivers in the world Up near the Grand Banks, the Stream is somewhat cooler and runs slower, but the volume of water it transports increases to at least 150 million cubic meters per second, something like 100 times the flow of water in all the rivers in all the countries of the world. A great-grandfather of waters, indeed, yet a flow often masked by fogs created by its passage under the cold air coming off the Canadian Maritime Provinces. Storms can make the Stream dramatically visible. A northeaster blowing down against the current combs it into nasty steep waves that make sailors miserable. The Wilmington ran into such a storm on a recent trip. Nothing of consequence got bent, but the crew took a beating, and the ship lost a lot of time. On this passage, though, the sea simply dozed. Swells on their "He was not eaten by sharks," Homer asserted, "and way to the sands of Florida slipped across the bow in was rescued by a passing ship not in the picture." close order, following on in a rhythm slow as sleep. In 47 The Stream and its mysteries such a duck pond, it was difficult to believe that there was a giant below, carrying me along as the demon beneath the keel carried the Ancient Mariner. It was even more difficult during the first days of European exploration . Ships then were blocky and slow. They could run before the wind or reach across it, but could beat toward it only obliquely and only with great difficulty. Against a wind and current, they were all but helpless. If the blue god caught them, escape could be difficult. There was little they could do but wait for a breeze from the right quarter . Chris- topher Columbus made the first reported crossing of the North Atlantic, running before the trade winds along the southern arc of the Gulf Stream's gyre (see map on pp.
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