Like land masses, oceans water varies in temperature from place to place both at the surface and at great depths. Since water warms up and cools down much more slowly than the land, the annual range of temperature in any part of the ocean is very much smaller. It is less than 10 degree F, for most of the open seas. Generally, the mean annual temperature of the surface ocean water decreases from about 70 degree F. in equatorial areas to 55 degree F. at latitudes 45 degree N and S, and drops almost to freezing-point at the poles. The reduction of temperature with latitude is however never constant, because of the interference by warm and cold currents, winds and air masses. Unlike the solid earth, ocean water is mobile and variations in temperature between different parts of the oceans can be expected. Water flowing out from the Arctic and Antarctica as cold currents, such as the Labrador Current off north-east Canada, tends to reduce the surface-water temperature. Ports of eastern Canada even at 45 degree N. are thus icebound for almost half the currents, such as the North Atlantic Drift, have their surface temperature raised. The Norwegian coast, even at latitudes 60 degree to 70 degree N. is ice free throughout the year!
The highest water temperatures are found in enclosed seas on the tropics, e.g. the Red sea which records a temperature of 85 degree to 100 degree F. The Arctic and Antarctic waters are so cold that their surface is permanently frozen as pack-ice down to a depth of several feet. In the warmer summer, parts of the ice break off as icebergs that both dilute the water and lower the surface temperature of surrounding ice-free seas.
The temperature of the oceans also varies varity cally with increasing depth. It decreases rapidly for the first 200 fathoms, at the rate of 1 degree F. for every 10 fathoms, and then more slowly until a depth of 500 fathoms is reached. Beyond this, the drop is scarcely noticeable, less than 1 degree F. for every 100 fathoms. In the ocean deeps below 2,000 fathoms (12,000 feet), the water is uniformly cold, just a little above freezing-point. It is interesting to note that even in the deepest ocean trenches, more than 6 miles below the surface, the water never freezes. It is estimated that over 80% of all ocean waters have a temperature between 35 degree and 40 degree F.
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The highest water temperatures are found in enclosed seas on the tropics, e.g. the Red sea which records a temperature of 85 degree to 100 degree F. The Arctic and Antarctic waters are so cold that their surface is permanently frozen as pack-ice down to a depth of several feet. In the warmer summer, parts of the ice break off as icebergs that both dilute the water and lower the surface temperature of surrounding ice-free seas.
The temperature of the oceans also varies varity cally with increasing depth. It decreases rapidly for the first 200 fathoms, at the rate of 1 degree F. for every 10 fathoms, and then more slowly until a depth of 500 fathoms is reached. Beyond this, the drop is scarcely noticeable, less than 1 degree F. for every 100 fathoms. In the ocean deeps below 2,000 fathoms (12,000 feet), the water is uniformly cold, just a little above freezing-point. It is interesting to note that even in the deepest ocean trenches, more than 6 miles below the surface, the water never freezes. It is estimated that over 80% of all ocean waters have a temperature between 35 degree and 40 degree F.
For more updates subscribe via email and stay tuned.
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