Among the other planets known, it is said that earth is the best planet to live in which can support and have intelligent life. It has the atmosphere, lithosphere and hydrosphere that are provided for man to have suitable life. It contains the composition and substances needed for man to exist. Earth is often called ‘Blue Planet’ because most of it is covered in water. In fact, about 71% of the earth is covered by water. Of this, almost 97% is formed in the oceans as saltwater, about 2.2% occurs as a solid in ice sheets, while the remaining amount (less than 1%) is available as freshwater (Free High School Science Tests Project).
Let us think on the roles done by the water in our lives. Oceans and seas occupy the greatest area on the earth’s surface. And it corresponds to a great benefit we humans can get on these bodies of water. Because of its vast coverage, it acts as a great heat reservoir, leveling the temperature extremes that would otherwise prevail over the earth and expand the desert areas. Oceans also can influence weather and changes on it can drive or moderate climate change.
There are so many other significant things the seas have brought to man. It provides habitat to many plants and animals. With this, the sea is a source of protein, primarily fish and other sea foods. Man can get about 60,000,000 tons of food from the ocean annually by fishing. If there is none of these we can get harvest from the seas, I think there would be famine. The sea is also a source of power, minerals and petroleum. There is this thing that energy is extracted from the tides of the ocean that could generate power. Tons of mineral materials can also be obtained from the sea. It is a treasure house of minerals. These minerals are useful and valuable such as magnesium, a light metal that is used in aircraft. And for all we know, the sea is the important source of ordinary salt needed by chemical industries. And about 2,000,000,000,000 barrels of oil resources can be obtained. Oceans also provide building products such as sand, gravel and lime. There are also jewelries like corals and pearls and fertilizers on seaweeds. Oceans and seas give us also the capability to travel in water through water transportations. And this has also enable exploration possible.
In the contrary, the much less volume of ground water provides its importance to human. Not like water resources from the oceans, it does not contain big amount of dissolved minerals making it suitable to meet the needs of man. Humans and animals depend upon water. And it is said that these biotic organisms are more likely faster to die on dehydration than starvation. Man needs about a gallon of water per day. They also use this for some chores or activities in their daily lives. Plants also need water for them to grow. Without water, there would be no plants that are one source of food for man. In addition, plants also exhale oxygen needed by man. It has also been written that ground water as an erosional agent is valuable because it has the ability to dissolve rocks. It could produce sinkholes creating subterranean coverns. It also acts as a storehouse that provides water to streams when rain does not fall at all.
The hydrosphere has helped man in many ways. We have life in it. It provides many functions to all creatures on earth. And I guess, we would not survive on this planet without dependence on water.
