Where Might You Find A Gyre

Many ocean gyres are found in what are called the horse latitudes, between 30 and 35 degrees north and south. These areas are known to have calm waters and little precipitation or winds.

Five permanent subtropical gyres can be found in the major ocean basins—two each in the Atlantic and Pacific Oceans and one in the Indian Ocean—turning clockwise in the Northern Hemisphere and counterclockwise in the Southern. Smaller counterclockwise gyres centered at around 60 degrees north latitude are created by the prevailing winds around permanent sub-Arctic low-pressure systems. Another subpolar gyre, the only one centered on a landmass, circles Antarctica driven by the near-constant westerly winds that blow over the Southern Ocean, unimpeded by land.

One of the most important roles of ocean currents is in governing Earth’s weather and climate. Western boundary currents such as the Gulf Stream carry large amounts of heat from tropical waters to the north. This flow is part of the thermohaline circulation, or ocean conveyor and helps distributes heat around the planet. This in turn governs wind patterns, air temperature and precipitation both locally and globally.

Wind is the primary force that creates and moves surface currents; Earths rotation plays an important role in steering the waters motion. Persistent subtropical high pressure systems centered at about 30 degrees north and south latitude create patterns of strong winds known as the trades and the westerlies. Friction between the air and the water sets the sea surface in motion. As this topmost layer of water moves, it pulls on the water directly beneath it, which in turn pulls on the layer of water beneath that to create the beginnings of an ocean current.

Once the fast-moving currents leave the confining influence of land, they become unstable and, like a fire hose with no one holding it, begin to meander and bend. If a current becomes so tightly bent that it doubles back on itself, that section of flow may “pinch off” and separate from the main body of the current like an oxbow bend in a river. These swirling features can take the shape of warm-core (masses of warm water turning in colder ocean waters) or cold-core (masses of cold water in warm) eddies and can travel for months across hundreds or thousands of miles of open ocean.

Simon Thorrold is an ocean ecologist at Woods Hole Oceanographic Institution. He uses techniques that span isotope geochemistry, next generation DNA sequencing, and satellite tagging to study the ecology of a wide variety of ocean species. He recently discovered that blue sharks use warm water ocean tunnels, or eddies, to dive to the ocean twilight zone, where they forage in nutrient-rich waters hundreds of meters down. Born in New Zealand, Simon received his B.S. from the University of Auckland, and Ph.D. from James Cook University, North Queensland, Australia. With much of his work in the South Pacific and Caribbean, Simon has been on many cruises, logging 1,000 hours of scuba diving and 800 hours in tropical environs. He has been a scientist at Woods Hole Oceanographic Institution since 2001.

Global winds drag on the water’s surface, causing it to move and build up in the direction that the wind is blowing. And just as the Coriolis effect deflects winds to the right in the Northern Hemisphere and to the left in the Southern Hemisphere, it also results in the deflection of major surface ocean currents to the right in the Northern Hemisphere (in a clockwise spiral) and to the left in the Southern Hemisphere (in a counter-clockwise spiral). These major spirals of ocean-circling currents are called “gyres” and occur north and south of the equator. They do not occur at the equator, where the Coriolis effect is not present (Ross, 1995).

One particularly powerful western boundary current is the Gulf Stream. The Gulf Stream, paired with the eastern boundary Canary Current, flanks the North Atlantic gyre. The Gulf Stream, also called the North Atlantic Drift, originates in the Gulf of Mexico, exits through the Strait of Florida, and follows the eastern coastline of the United States and Newfoundland. It travels at speeds of 25 to 75 miles per day at about one to three knots (1.15-3.45 miles per hour or 1.85-5.55 kilometers per hour). It influences the climate of the east coast of Florida, keeping temperatures warmer in the winter and cooler than the other southeastern states in the summer. Since it also extends toward Europe, it warms western European countries as well.

A gyre is a vortex of gas or liquid. In terms of oceanography (since that is where this question has been asked) it refers to any large system of rotating ocean currents.

FAQ

Where are the 5 major gyres located?

Where Are the 5 Major Ocean Gyres? There are five identified permanent oceanic gyre currents: the North Atlantic, the South Atlantic, the North Pacific, the South Pacific, and the Indian Ocean.

What is a gyre quizlet?

Gyre. Large circular moving loops of water that are driven by the major wind belts of the world.

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