Olsen notes that “the favorable wind and ocean currents (Gyres) extend only as far a Malay, making a trip to the Americas much more impractical than a trip to the Malay Peninsula.”
A gyre in oceanography is any system of rotating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis Effect—the planetary vorticity (spin, rotation) along with horizontal and vertical friction, which determine the circulation patterns from the wind curl (torgue—rotating an object around an axis). The term gyre can be used to refer to any type of vortex in the air or the sea, even one that is man-made, but it is most commonly used in oceanography, to refer to the major ocean systems.
There are five major gyres in the world: North Atlantic, South Atlantic, Indian Ocean North Pacific and South Pacific. The gyre to which Olsen refers is the Indian Ocean Gyre which, being in the southern hemisphere, rotates counter-clockwise, making it impossible to reach the Indonesian islands from the west, since this current moves across the southern Indian Ocean from west to east, then northward along the coast of Australia (called the Australian Current and the Trade Winds that blow northwest from Australia), then back west across the northern Indian Ocean in a complete circle. This gyre, contrary to what Olsen claims is the movement that brings shipping south from the Arabian Coast, across the Arabian Sea, south through the Indian Ocean, then curving east into the Prevailing Westerlies and the West Wind Drift of the Southern Ocean, a current that leads directly to the west coast of South America.
In addition, there is what is called the Indian Monsoon Gyre, which is a weak current that also circles in a counter-clockwise direction. This is the gyre that Olsen uses, however, this gyre is affected by the Trade Winds that blow northwest off the Australian Coast toward the western Arabian Sea. These trade winds are from the east to southeasterly which affect tropical and subtropical regions, including the northern areas of Australia. During the monsoon season in northern Australia, the easterly trade winds are replaced by moist northwesterly (monsoonal) winds from the Indian Ocean and southern Asian ocean waters. In both hemispheres, these trade winds blow from the east to the west and towards the equator. Sometimes the trade winds will just be called "easterly" to avoid having to specify the hemisphere (meaning they come out of the east). Based on assembled data on ship drifts, winds and Ekman drift, and geostrophic currents derived from altimetry and hydrography to evaluate the observed climatological seasonal cycle of the monsoon currents, we find that these currents are the seasonally reversing, open-ocean currents that flow between the Arabian Sea and the Bay of Bengal, the two winds of the north Indian Ocean. The Summer Monsoon Current flows eastward during the summer monsoon (May–September), and the Winter Monsoon Current flows westward during the winter monsoon (November–February), and extend over the entire basin, from the Somali coast to the eastern Bay of Bengal. They do not, however, come into being, or decay, over this entire region at a given time. Different parts of the currents form at different times, and it is only in their mature phase that the currents exist as trans-basin flows.
The winds and currents along the Bay of Bengal in the Monsoon Gyre Olsen indicates, is blocked from further eastern movement by the Andaman and the Nicobar Islands that extend between Burma and Sumatra. Thus, there is no gyre that moves to Malay as claimed.(See the next post, “Problems With Malay Theory Part IV,” to see how Olsen reaches his Land of Promise across the Indian Ocean)
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