Importance of Earth's Hydrosphere

 

  

   HYDROSPHERE

 

The movement of water around, over, and through the Earth is called the water cycle, a key process of the hydrosphere. In physical geography, the term hydrosphere (Greek hydro means “water”) describes the collective mass of water found on, under, and over a planet’s surface. The earth’s hydrosphere consists chiefly of the oceans, but technically includes clouds, rivers, lakes, inland seas and underground waters. Hydrosphere refers to that portion of the Earth that is composed of water. The hydrosphere represents one component of the Earth’s system, operating in the conjunction with the solid crust (lithosphere) and the air that envelops the planet (atmosphere). 

On Earth, water exists in three primary states of matter; liquid, solid and gas. The distance of the Earth from the sun, fortunately, is such that the amount of energy arriving at the surface of most of the planet is sufficient to elevate the ambient temperature levels above the freezing point of water, yet insufficient to cause all of the water to evaporate into the gaseous state. The capacity of water to store large quantities of heat energy heavily influences the nature of the global climate. The presence of the large bodies of water and the atmosphere restrict the range of temperature fluctuations on Earth.

These conditions have allowed the existence of the fourth component of Earth’s system, the biosphere. Water is constantly being cycled through its various manifestations and through the components of Earth's systems by means of the hydrologic cycle. . Driven by solar energy, water is evaporated from the ocean surface and distributed over the earth as water vapor. Precipitation returns the water, in liquid and solid forms, to other parts of the globe.

The Importance of the Hydrosphere

 It is so easy sometimes to take our hydrosphere for granted and we seldom take the time to really think about the role that this part of the planet plays in keeping us alive. Below are just some of the very important functions of water in the hydrosphere: 

Water is a part of living cells

Each cell in a living organism is made up of almost 75% water, and this allows the cell to function normally. In fact, most of the chemical reactions that occur in life, involve substances that are dissolved in water. Without water, cells would not be able to carry out their normal functions and life could not exist.

 Water provides a habitat

The hydrosphere provides an important place for many animals and plants to live. Many gases (e.g. CO2, O2), nutrients e.g. nitrate (NO3), nitrite (NO2) and ammonium (NH4+) ions, as well as other ions (e.g. Ca2+ and Mg2+) are dissolved in water. The presence of these substances is critical for life to exist in water.

 Regulating climate

One of water's unique characteristics is its high specific heat. This means that water takes a long time to heat up and also a long time to cool down. This is important in helping to regulate temperatures on earth so that they stay within a range that is acceptable for life to exist. Ocean currents also help to disperse heat.

 Human needs

Humans use water in a number of ways. Drinking water is obviously very important, but water is also used domestically (e.g. washing and cleaning) and in industry. Water can also be used to generate electricity through hydropower. There are a lot of things that human do in their daily lives and water is not absent in everything people do.