Ocean is the world’s largest source of oxygen and the habitat for a variety of marine life. It regulates the global climate and provides a means of trade and transport. In addition, its ecosystems provide millions of people with a sustainable source of food and income. But the Ocean also faces a number of threats from human activities.
The word ocean is most often used to refer to the world’s salty seas, but it can also describe any large body of water, including lakes, rivers, streams and ponds. The ocean contains a huge amount of water, about 70% of Earth’s surface. It covers more than 2.7 billion square kilometers (1.1 billion square miles).
Water moves in a variety of ways in the oceans. It is drifted by winds, and influenced by the rotation of the Earth on its axis and by its tilt in relation to the sun. Temperature and salinity variations, which affect density, can induce or block water movement as well.
Ocean currents are largely created by friction between layers of the water. These frictional forces are caused by varying temperatures, density and the Coriolis effect. The rotation of the Earth also effects ocean currents, with wind pushing the waters in a clockwise direction in the Southern Hemisphere and counterclockwise in the Northern.
When the water’s temperature is warmer, it has more energy and is able to hold more dissolved gases, especially oxygen. This enables it to move faster. When the water’s temperature is cooler, it has less energy and is able to move more slowly.
In tropical waters, the difference between the warm surface and the colder depths creates distinct boundaries known as thermoclines, haloclines or chemoclines. These boundaries can cause dramatic changes in the water’s color and chemistry. In polar regions, the differences between surface and deep water are usually much less pronounced.
As a liquid, water is nearly incompressible, so it flows at different speeds over the surface and at various depths. Its surface speed decreases with increasing distance from the coast, while its vertical movements, which are influenced by upwelling and downwelling, vary at different rates depending on location.
In addition to its physical properties, the ocean is full of nutrients and minerals. The salt in sea water is antiviral and antibacterial, and its high iodine content promotes good health. It is also rich in magnesium, which helps the body to absorb calcium and phosphorus and enhances wound healing.
Swimming in the Ocean is a great way to exercise and improve your cardiovascular system, as it stimulates circulation by forcing your heart to work harder against the resistance of the water. It also delivers oxygen-rich blood to your muscles, organs and tissues, allowing them to function better and recover more quickly. As a result, your whole body will feel healthier after exercising in the Ocean.