Oceans cover two-thirds of the world's surface and are home to a diverse range of plants and animals. Clear water, white, sandy beaches and coral reefs teeming with colorful fish all characterize tropical oceans. Temperate oceans are more blue-green and famous for their bountiful supply of fish. Location and surface temperature of the water distinguish these two areas.
Tropical oceans lie between the Tropic of Capricorn and the Tropic of Cancer and include the central parts of the Pacific Ocean and the Atlantic Ocean, as well as the Indian Ocean. Average temperatures exceed 68 degrees Fahrenheit -- 20 degrees Celsius -- and remain constant throughout the year.
In the Northern Hemisphere, temperate oceans are located between the Tropic of Cancer and the Arctic Circle. In the Southern Hemisphere, temperate seas lie between the Tropic of Capricorn and the Southern Ocean. Temperatures range from 50 to 68 degrees Fahrenheit -- 10 to 20 degrees Celsius -- and fluctuate with the seasons.
Tropical waters are crystal clear, while temperate waters are a murky blue-green color. Plankton gives the water a bluish-green appearance. The more murky the water, the more plankton it contains. Plankton are tiny organisms that float near the ocean surface. They obtain their energy through photosynthesis and are eaten by many creatures low on the food chain.
The majority of fish served in restaurants or bought at markets to be cooked at home are caught in temperate seas. The high plankton concentration allows large schools of fish to thrive. The high concentration of fish sustains birds and mammals, as well as humans. These include Atlantic herring, abalone, cod, hake, halibut, haddock, mackerel, monkfish, swordfish, salmon, blue mussels, northern lobsters and king crabs.
The Ocean and Weather
The tropical oceans play a critical role in regulating the Earth's weather patterns. The sun shines squarely on the waters around the equator all year. Warm surface water is evaporated, forming a mass of warm, humid air. This air cools as it travels north and south, condensing into clouds. The clouds grow heavy and precipitation, or rain, occurs. The rain is vital for rain forests in tropical climates and agriculture in more temperate climates.