Our hydrosphere plays a very important rule in the substance and development life, because of it the earliest living organisms emerged. Also human life begins in water, without water we are nothing. First of everything do we know what is truly a hydrosphere and what do it meant?

Hydrosphere comes from a Greek word hydro means "water" describes the collective mass of water.

 It is all water at and near the earth’s surface that is not chemically bound in rocks. The total mass of the earth’s hydrosphere is about 1.4 × 10¹⁸ tonnes which about 0.023% of the total mass of the earth. The total volume of water at or near the earth surface is approximately 1,500,000,000 cubic kilometers, which almost the 99% contained the discontinuous oceanic water layer. The thickest hydrosphere is thought to exist around the Jovian moon Europa. The outer layer of this hydrosphere is entirely ice. A hydrosphere is the component of liquid water on Earth. A hydrosphere includes oceans, seas, lakes, ponds, rivers and streams. The hydrosphere consists of the bodies of water that cover 71 percent of Earth’s surface. The largest of these are the oceans, which contain over 97 percent of all water on Earth. It is always in motion; also it is called the “water sphere”. Water exist in three phases; solid, liquid, and gas or vapor. Water vapor is an odorless, colorless and tasteless. It freely mixes with the other gasses at the atmosphere. It easily changes from one phase to another with a certain temperature and pressure. This ability allows water to leave oceans as a gas and return again as a liquid, it is called the water cycle or horological cycle.

 

    

Liquid water is colorless, odorless, tasteless, has a freezing point of 0 degrees Celsius and a boiling point of 100 degrees Celsius at one atmosphere. Also water has different process the melting, sublimation, evaporation, freezing, condensation, deposition. Melting is the process which a solid changes to liquid, it requires absorption of 80 calories of heat for every gram of water. The sublimation is a term used to describe the change from solid to gas without passing the liquid phase, the reverse process where vapor changes to solid is deposition. The evaporation is a process of changing liquid water into vapor state. Freezing is the process which is changing liquid to solid. Condensation is the process of water vapor changing to the liquid state.

About 3% of the earth surface water is fresh water; the 

rest 97% is stored in ocean as saltwater.

Water is a rather unusual earth material because it can exist in all phases of matter. It could be found as a liquid in the ocean, as a solid like glaciers and in gas in the atmosphere.