Atlantic Ocean - Wikipedia
The Atlantic Ocean is the second largest of the world's oceans, with an area of about .. Ocean currents influence climate by transporting warm and cold waters to . Ocean Agulhas Current meet to produce an intertidal zone on which shellfish, . hovered around 2 °C (36 °F) which made farming favorable at high latitudes. Areas where warm air rises and cools are centers of low atmospheric pressure. In general, the surface along which a cold air mass meets a warm air mass Tropical cyclones are dangerous because of their high winds, the storm of existing low and high pressure systems, as well as the Coriolis force. This review attempts to provide some sense of our current knowledge of water . The mechanism of thirst is quite well understood today and the reason and milk , and are used in warm weather for cooling and in cold weather for warming. . In general, provision of water is beneficial in those with a water deficit, but little.
In the southeast, the Atlantic merges into the Indian Ocean. Mid-Atlantic Ridge The MAR divides the Atlantic longitudinally into two halves, in each of which a series of basins are delimited by secondary, transverse ridges.
The MAR is a barrier for bottom water, but at these two transform faults deep water currents can pass from one side to the other. While nine of these have collectively been nominated a World Heritage Site for their geological value, four of them are considered of "Outstanding Universal Value" based on their cultural and natural criteria: Continental shelves in the Atlantic are wide off Newfoundland, southern-most South America, and north-eastern Europe. In the western Atlantic carbonate platforms dominate large areas, for example the Blake Plateau and Bermuda Rise.
The Atlantic is surrounded by passive margins except at a few locations where active margins form deep trenches: There are numerous submarine canyons off north-eastern North America, western Europe, and north-western Africa. Some of these canyons extend along the continental rises and farther into the abyssal plains as deep-sea channels.
This involved little guesswork because the idea of sonar is straight forward with pulses being sent from the vessel, which bounce off the ocean floor, then return to the vessel. Based on temperature Ocean currents are classified based on temperature: Cold currents bring cold water into warm water areas [from high latitudes to low latitudes].
These currents are usually found on the west coast of the continents currents flow in clockwise direction in northern hemisphere and in anti-clockwise direction in southern hemisphere in the low and middle latitudes true in both hemispheres and on the east coast in the higher latitudes in the Northern Hemisphere; Warm currents bring warm water into cold water areas[low to high latitudes] and are usually observed on the east coast of continents in the low and middle latitudes true in both hemispheres.
In the northern hemisphere they are found on the west coasts of continents in high latitudes. General Characteristics of Ocean Currents Characteristics of Ocean Currents arise due to the interplay of the above-mentioned factors.
Water, Hydration and Health
The general movement of the currents in the northern hemisphere is clockwise and in the southern hemisphere, anti-clockwise. A notable exception to this trend is seen in the northern part of the Indian Ocean where the current movement changes its direction in response to the seasonal change in the direction of monsoon winds. The warm currents move towards the cold seas and cool currents towards the warm seas.
In the lower latitudes, the warm currents flow on the eastern shores and cold on the western shores [food for imagination]. The situation is reversed in the higher latitudes. The warm currents move along the western shores and the cold currents along the eastern shores. The shape and position of coasts play an important role in guiding the direction of currents. The currents flow not only at the surface but also below the sea surface due to salinity and temperature difference.
For instance, heavy surface water of the Mediterranean Sea sinks and flows westward past Gibraltar as a sub-surface current. Effects of Ocean Currents Ocean currents have a number of direct and indirect influences on human activities. Desert formation Cold ocean currents have a direct effect on desert formation in west coast regions of the tropical and subtropical continents. There is fog and most of the areas are arid due to desiccating effect loss of moisture. Rains Warm ocean currents bring rain to coastal areas and even interiors.
Summer Rainfall in British Type climate. Warm currents flow parallel to the east coasts of the continents in tropical and subtropical latitudes. This results in warm and rainy climates. These areas lie in the western margins of the subtropical anti-cyclones.
Water, Hydration and Health
Moderating effect They are responsible for moderate temperatures at coasts. Canary cold current brings cooling effect to Spain, Portugal etc. The mixing of warm and cold currents help to replenish the oxygen and favor the growth of planktons, the primary food for fish population.
The best fishing grounds of the world exist mainly in these mixing zones. Drizzle Mixing of cold and warm ocean currents create foggy weather where precipitation occurs in the form of drizzle [Newfoundland]. Climate Warm and rainy climates in tropical and subtropical latitudes [Florida, Natal etc. Tropical cyclones They pile up warm waters in tropics and this warm water is the major force behind tropical cyclones.
Ships usually follow routes which are aided by ocean currents and winds. If a ship wants to travel from Mexico to Philippines, it can use the route along the North Equatorial Drift which flows from east to west. When it wants to travel from Philippines to Mexico, it can follow the route along the doldrums when there is counter equatorial current [we will study this in next post] flowing from west to east. Explain the factors responsible for the origin of ocean currents.
The aridity of the hot deserts is mainly due to the effects of off-shore Trade Winds, hence they are also called Trade Wind Deserts.
They include the biggest Sahara Desert 3. The next biggest desert is the Great Australian Desert. The hot deserts lie along the Horse Latitudes or the Sub-Tropical High Pressure Belts where the air is descending, a condition least favorable for precipitation of any kind to take place.