The % of earth covered by oceans is about
The percentage of total quantity of water in the world that is saline is about
The percentage of total quantity of fresh water in the world available in the liquid form is about .
About 71 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water. Also, % of total water available in liquid form out of total quantity of freshwater is 30% and rest is in form of ice and glaciers.
A catchment has an area of 150 ha and a runoff/ rainfall ratio of 0.40. If due to a 10 cm rainfall over the catchment a stream flow at the catchment outlet lasts for 10 hours, the average stream flow in the period is
The average stream flow
A catchment of area 120 km2 has three distinct zones as below
The annual runoff from the catchment, in cms, is
Annual run off
If the average annual rainfall and evaporation over land masses and oceans of the earth are considered it would be found that
Whenever precipitation occurs, a part of rainfall is infiltrated into the soil and other part is surface runoff meeting in the rivers.
Moreover, not all the water evaporated from the sea is transported towards land and most of it fall back as precipitation in oceans itself.
Therefore, it is found that about 9% more, water evaporates from the ocean than what falls back them as precipitation.
In the hydrological cycle the average residence time of water in the global
What is ‘Hydrological Cycle’?
Most of the earth’s water sources such as rivers, fakes, oceans, ground water, etc, get their supplies
from rain, while the rain water in itself is derived from the evaporation from these sources.
Water is intact lost to the atmosphere as vapour from the earth, which is then precipitated back in the form of rain, snow, hail, dew, sleet or frost, etc. This evaporation and precipitation continues forever and thereby, a balance is maintained between the two. This process is known as hydrologic cycle.
The hydrologic cycle states that