What is an example of a wind-driven current?
The Southern Ocean contains a large, wind-driven current, the Antarctic Circumpolar Current, which carries approximately 170 × 106 m3 of water eastward around Antarctica within multiple filamented jets.
What causes winds to current?
In the Northern Hemisphere, for example, predictable winds called trade winds blow from east to west just above the equator. The winds pull surface water with them, creating currents. As these currents flow westward, the Coriolis effect—a force that results from the rotation of the Earth—deflects them.
Where is upwelling most common?
Upwelling is most common along the west coast of continents (eastern sides of ocean basins). In the Northern Hemisphere, upwelling occurs along west coasts (e.g., coasts of California, Northwest Africa) when winds blow from the north (causing Ekman transport of surface water away from the shore).
What kind of ocean current is called a drift give an example?
Answer:
| Current | Drift |
|---|---|
| 1. A massive, horizontal water flow of surface-ocean water as a broad stream in a definite direction is termed as ocean current. | 1. A large volume of slow-moving ocean water is known as a drift. |
| 2. Examples: Peru current and Labrador current | 2. Examples:North Atlantic drift and West Wind drift |
What type of ocean current is driven by wind?
In each case, the wind-driven circulation is divided into gyres that stretch across the entire ocean: subtropical gyres extend from the equatorial current system to the maximum westerlies in a wind field near 50° latitude, and subpolar gyres extend poleward of the maximum westerlies.
What are the causes of currents?
Ocean currents are driven by wind, water density differences, and tides….Oceanic currents are driven by three main factors:
- The rise and fall of the tides.
- Wind.
- Thermohaline circulation.
What are upwellings and Downwellings?
Downwelling is where surface water is forced downwards, where it may deliver oxygen to deeper water. Downwelling leads to reduced productivity, as it extends the depth of the nutrient-limited layer. Upwelling occurs where surface currents are diverging, or moving away from each other.
How is the ocean’s food chain influenced by upwelling?
Effects of Upwelling Because the deep water brought to the surface is often rich in nutrients, coastal upwelling supports the growth of seaweed and plankton. These, in turn, provide food for fish, marine mammals, and birds. Upwelling generates some of the world’s most fertile ecosystems.
What nutrients does upwelling bring to the surface?
Upwelling brings cold water from the deep ocean to the surface. This cold water is typically rich in nutrients such as nitrate and phosphate because of the dead and decaying matter that has sunk to the ocean floor. These nutrients are important for the primary producers of the oceanic food chain, the phytoplankton.
What are the effects of ocean currents on human life?
Ocean currents affect the shipping industry, commercial and recreational fishing, and recreational navigation for boats. Having updated information on currents is directly related to how safely people can dock or navigate along coasts. Ocean currents play a role in the distribution of pollution, such as oil spills.
What is drift current and stream?
Difference between Drifts, Current and Streams The forward movement of surface water of the oceans under the influence of prevailing winds is called drift whereas the ocean current involves the movement of Oceanic water in a definite direction with greater velocity.
What are the three items that cause the currents in the ocean?
Oceanic currents are driven by three main factors:
- The rise and fall of the tides. Tides create a current in the oceans, which are strongest near the shore, and in bays and estuaries along the coast.
- Wind. Winds drive currents that are at or near the ocean’s surface.
- Thermohaline circulation.
How does the Coriolis effect affect human life?
The weather impacting fast-moving objects, such as airplanes and rockets, is influenced by the Coriolis effect. The directions of prevailing winds are largely determined by the Coriolis effect, and pilots must take that into account when charting flight paths over long distances.
What are some examples of the Coriolis effect?
Thus, if a cannon were fired northward from a point on the Equator, the projectile would land to the east of its due north path. This variation would occur because the projectile was moving eastward faster at the Equator than was its target farther north.
How do upwellings work?
Winds blowing across the ocean surface push water away. Water then rises up from beneath the surface to replace the water that was pushed away. This process is known as “upwelling.” Upwelling occurs in the open ocean and along coastlines.
What happens to the productive food chain during an El Niño?
However, El Niños can also cause ecosystem and food chain effects that may be less obvious but are no less important or dramatic. One small change in a food chain can cause rippling and dramatic effects across interconnected food chains within a larger food web.