Correct Option
The correct option is 1, 2, 3 and 4.
Explanation
The temperature of ocean water is not uniform across the globe. It varies horizontally and vertically due to differences in insolation, heat transfer, and physical movement of water masses. Several geographical and meteorological factors influence this distribution.
Statement-wise Analysis
- 1. Latitude (Correct): The temperature of surface water decreases from the equator towards the poles. This is because the amount of insolation (incoming solar radiation) decreases as the sun's rays become more oblique at higher latitudes.
- 2. Unequal distribution of land and water (Correct): The oceans in the Northern Hemisphere receive more heat due to their contact with extensive landmasses, compared to the oceans in the Southern Hemisphere. Consequently, isotherms often deviate based on the proximity to land.
- 3. Prevailing wind (Correct): Winds influence the horizontal distribution of temperature.
- Offshore winds drive warm surface water away from the coast, resulting in the upwelling of cold water from below (lowering temperature).
- Onshore winds pile up warm water near the coast (raising temperature).
- 4. Ocean currents (Correct): Ocean currents are the primary mechanism for redistributing heat. Warm ocean currents raise the temperature in cold areas, while cold currents lower the temperature in warm coastal areas (e.g., the Gulf Stream raises the temperature of the North-Western European coast).
Key Takeaway
Key Takeaway: The surface temperature of ocean water is primarily determined by latitude (insolation), land-sea contrast, prevailing winds (upwelling/downwelling), and ocean currents (heat transport).