Evolution of Hydrosphere

EVOLUTION OF HYDROSPHERE

Hydrosphere refers to the total water available on earth. Oceans, seas, rivers, lakes, and glaciers are part of the hydrosphere. The water on our planet is presented in three forms solid, liquid, and gas. The evolution of the hydrosphere has the following stages-

STAGE 1- AGE OF DEGASSING

The degassing accumulates water vapors and gases into the atmosphere. It is believed that these gases and water vapors are released from within the interior of the earth through volcanic eruptions, hot springs, and geysers.

STAGE 2- AGE OF CONDENSATION AND PRECIPITATION

As the earth cooled, the water vapor starts to condense, and carbon dioxide mixed with rainwater further reduces the temperature causing more precipitation in the form of rain, snow, hail, etc.

STAGE 3- AGE OF RAINWATER HARVESTING

The rainwater collected in depressions gives rise to the present form of the world’s oceans. It takes 500 million years to form oceans and they are 4000 million years old.

Continents and oceans are considered “relief features of the first order”. About 71% of the total surface area of the earth is dominated by oceans. The oceans contain 97% of the total volume of water. Water dominates the southern hemisphere. Thus, the southern hemisphere is known as the “Water Hemisphere”. The ocean of the world can further be divided into two parts i.e., the aqua sphere and cryosphere. The word aqua sphere refers to the liquid form of water and the word cryosphere refers to the solid form of water (Ice), respectively.

WORLD OCEAN

Oceans

Area (106km2)

Average depth (m)

The area of the earth’s surface (%)

PACIFIC OCEAN

181.34

3,940

35.5

ATLANTIC OCEAN

94.31

3,844

18.4

INDIAN OCEAN

74.11

3,840

14.5

ARCTIC OCEAN

12.25

1,117

2.4