Explanation:

• Like land masses, ocean water varies in temperature from place to place both at the surface and at great depths. Unlike the solid earth, ocean water is mobile and variations in the temperature between different parts of the oceans can be expected. • Water flowing out from the Arctic and Antarctic as cold currents, such as the Labrador Current off northeast Canada, lends to reduce the surface-water temperature. Ports of eastern Canada even at 45°N, are thus icebound for almost half the year. • In the same way, coasts warmed by warm currents, such as the North Atlantic Drift, have their surface temperature raised. • Therefore, the Norwegian coast, even at latitudes 60° to 70°N. is ice-free throughout the year. Hence, statement II is correct and is the correct explanation of Statement I. • The highest water temperatures are found in enclosed seas in the tropics, e.g. the Red Sea which records a temperature of 85° to I00°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 vertically with increasing depth. It decreases rapidly for the first 200 fathoms, at the rate of 1°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 I°F. for every 100 fathoms. In the ocean deep 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 per cent of all ocean waters have a temperature between 35° and 40°F