Rain is water droplets that are formed due to condensation from the water vapour present in the atmosphere that falls down on earth due to the impact of gravity. Rain is the primary part and outcome of the water cycle. The course of rain is associated with the precipitation of the water drops on earth. This phenomenon begins with the stages of the water cycle that in turn lead to the rainfall on earth and the cycle continues further on. Rainfall occurs when the clouds up in the sky become too heavy to float in the sky and then they precipitate onto the ground as rain.
Rain is nothing but the water droplets that fall on the earth in form of liquid. These were generally condensed from the water vapour present in the atmosphere. Rain can fall on earth as long as the temperature is above the freezing level that is 32°F. It is primarily one of the, if not, the most important part of the entire course of the water cycle.
Figure 1: Rain
Rainfall supports the life forms on earth as it continues to deposit fresh water on earth. Hence, it is highly crucial for sustenance on earth. Multiple uses are drawn out from rainfall most importantly it is helpful in the production of electricity. It falls on earth and then seeps into the soil enriching it with moisture and other nutrients.
The course of rainfall begins with evaporation contributing to the water cycle. The air rises through evaporation and condensation up in the air that leads to the formation of clouds. These clouds are constituted of water droplets that gradually grow. Eventually, the clouds become too heavy to linger up in the sky and they fall on the ground as rain.
Figure 2: Rain formation
The course of rainfall begins as the sun heats the air that eventually leads to the rising of warm air up in the atmosphere. The air eventually cools down, condensation occurs and clouds will form that constitute a vast number of water droplets. The water in the cloud becomes quite heavy for the air currents to hold them up and eventually they fall to the ground.
Clouds found in the sky are formed in certain ways. Some of the procedures are mentioned below −
Mostly clouds are formed when the air around the surface of earth warms up and rises in the atmosphere. The heat generated by the incoming sunlight heats the ground, which in turn heats the air above, and eventually creates clouds.
Clouds are classified into various sections based on their shapes and sizes. Some of these clouds are termed lenticular and stratus clouds. These clouds come into existence when the blowing wind around the edges of mountain ranges is forced to attain high altitudes in the atmosphere.
Almost all of the clouds are created as the air is forced to reach up around the low-pressure regions. It causes the formation of cirrocumulus, altostratus, stratus clouds and other types of clouds.
The stages of the water cycle are accompanied by various other natural events. This cycle is also influenced by several human activities. The water cycle is also termed the hydrological cycle and it leads to a constant circulation of water. This event occurs through the following stages:
Figure 3: Water Cycle
In the course of evaporation, water evaporates and the heat from sunlight alters the state of water from liquid to gaseous state.
Water is also absorbed into the atmosphere of the earth from trees and plants
Melting occurs in the next stage where the snow and ice found in the arctic region are converted into the liquid state
Dust and other particle found in the atmosphere also catalyze the procedure of formation of clouds through movement.
In the final stage when the water droplets become too heavy up in the sky they precipitate down on the earth as rain, drizzle, or snowfall. These precipitated droplets get evaporated back in the presence of sunlight continuing the course of water cycle.
Rain is quite important for all the life forms existing on earth. It appears as liquid precipitation that falls from the sky. This rainfall then nourishes the ambience, soil, and the flora and fauna of a region. Some importances are mentioned below.
It helps in the growth of plants.
It helps in sustaining the water level on the ground.
Rain is quite useful in multiple human activities, like farming, the generation of electricity, etc.
It contributes to the freshwater for the water cycle.
It cools the atmosphere.
Rainfall breathes a new life on earth. It is quite necessary for the living organisms existing on planet earth. Rainfall is a direct outcome of the water cycle. It benefits the ambience with nourishment, and temperature moderation. It is considered a major type of precipitation along with snowfall, sleet, and hail. Rainfall is the result of the water cycle, the course of action that leads to precipitation.
Q1. What is infiltration in the water cycle?
Ans. Infiltration is associated with the state that assists the course of rainfall on earth that seeps into soil filing up the ground soil basin. The soil then stores the water under the ground. It is a crucial stage in the water cycle.
Q2. What is the importance of the sun in the water cycle?
Ans. The heat generated by the sun causes the water droplets to evaporate and turn them into water vapour that rises in the atmosphere leading to rainfall on earth. It is the basic requirement for the water cycle.
Q3. What is condensation?
Ans. The water that rises in the air due to the presence of water vapour condenses up in the air as it goes up where the temperature gets cold, and clouds are formed. This stage is called condensation.