Water Cycle

What is Water Cycle?

Water Cycle, also known as hydrologic cycle is the process that collects, purifies and circulates the earth’s finite water supply. During the process, water changes its form multiple times, but the mass remains constant.
When it precipitates, the rainwater runs along the ground surface and flows into water bodies or directly into the sea. A part of the rainwater percolates into the land and recharges the groundwater aquifers through infiltration. Some water directly evaporates into the air while some of it is absorbed by the plants and returned to the atmosphere through the leaves, both as water vapours. This process is called Evapotranspiration. Water vapour rises in the air as they have lighter molecules and hence form clouds. With less temperature at higher altitudes, the water vapours condense into tiny water droplets and fall back on the earth’s surface as precipitation. Some of this water gets trapped in glaciers and other water bodies, and through the above-mentioned processes, the endless water cycle continues.

Recently, the water cycle has been intensified because of the phenomenon of global warming. It is being accelerated, and as a result, extreme water-related hazards can occur. This is because the warmer weather due to climate change is increasing evaporation. With the increase in evaporation many water bodies and seas are drying up and more water vapours are circulating in the atmosphere. They will eventually precipitate back to the earth but will end up causing unwanted storms and floods. The only way to tackle this problem is to take better care of the environment.

During this process of water cycling, water changes its state from one phase to another, but the overall number of water particles remains constant throughout. In other words, even if it were feasible to gather and boil 100 gms of water, it would still retain a mass of 100 gms as steam after the process. In the same way, if 100 gms of steam is collected and condensed, the resulting water will still weigh 100 gms as well.

In addition to evaporation, melting, and freezing, water can change its state through the processes of sublimation, condensation, and deposition. Applied energy is required for each of these transformations.

Stages of Water cycle

The movement of water is the result of a variety of mechanisms. Each of the steps of the water cycle is listed in the next section.

1. Evaporation is a process in which water evaporates.

Earth’s primary source of energy is the sun, which is responsible for the vast majority of the evaporation that occurs on the planet. Evaporation occurs when water molecules on the surface of water bodies become stimulated and ascend into the air, which is the most common cause of the phenomenon. Water vapor clouds form as a result of the accumulation of molecules with the highest kinetic energy.. In most cases, evaporation takes place when water is over its boiling point. When evaporation happens through the leaves of plants, another process known as evapotranspiration occurs. Water is released into the atmosphere as a result of this process in massive quantities.

2. Sublimation is the second method of transformation.

It is possible for snow or ice to sublimate, resulting in the formation of water vapor instead of water. When there are dry winds and little humidity, this type of cloud formation is common. On mountain tops, where the air pressure is extremely low, sublimation can be witnessed. It takes less energy to sublimate snow into water vapor because of the low air pressure, which makes the process faster and more efficient. An additional example of sublimation is the phase in which fog rises from dry ice, which is called the bellowing phase. The ice sheets that cover the planet’s poles are the principal source of sublimation on the planet’s surface.

3. Condensation is a process that occurs when two or more substances come together.

Because of the low temperatures seen at high altitudes, the water vapor that has accumulated in the atmosphere ultimately cools down. Once transformed into small droplets of water and ice, these vapors eventually condense as clouds.

4. Precipitation is a fourth factor to consider.

When the temperature rises above 0 degrees Celsius, the vapors condense and form water droplets. Without dust or other impurities, it, on the other hand, cannot condense. So the surface of the particle is covered with water vapor, which attracts the particle. The water drops from the clouds to the land below when a sufficient number of droplets combine. Precipitation is the name given to this process (or rainfall). The water droplets freeze and fall as snow or hail in especially cold weather or when air pressure is extremely low.

5. Infiltration

Infiltration is the process through which rainwater seeps into the ground and is absorbed. Based on the type of material into which the water has penetrated, the level of absorption differs from one material to another. For example, boulders will hold on to water far less effectively than soil will. Either streams or rivers can carry groundwater downstream. The water may also sink further, forming aquifers, in some cases.

6. Runoff

It follows gravity if rainfall does not collect in underground storage aquifers, frequently running down the sides of mountains and hills and eventually into rivers. A technique known as runoff is used to describe this action. As temperatures drop, the volume of snow that falls outpaces the rate at which it evaporates or sublimates, resulting in ice cap formation in colder places. Poles are home to some of the world’s largest ice caps.

Everything described above occurs in a cyclical fashion, with neither a distinct beginning nor an identifiable finish.

The Water Cycle and Its Implications.

• In terms of climate change, the water cycle has a significant effect. Temperatures will rise as a result of the greenhouse effect, to name one example. It is estimated that the temperature on Earth would rise by several degrees Celsius if the water cycle did not exist.
• It is also a component of the other biogeochemical cycles, including the carbon dioxide cycle.
• On Earth, the water cycle has an impact on all of the living processes.
• Also known as “air purification,” the water cycle helps to keep the air clean. During the process of precipitation, for example, water vapors must attach themselves to dust particles in order to function properly. Apart from dust, raindrops laden with pollutants and water-soluble gasses that fall from the clouds in polluted cities also pick up water-soluble gasses and contaminants. Biological agents such as bacteria, as well as industrial soot particles and smoke, have been observed to be picked up by raindrops on occasion.

Conclusion

The intensity of climate variability and change is influenced by the amount of water available. During extreme weather events, such as drought and flooding, it is a critical component. When it comes to addressing the requirements of humans and ecosystems, its availability and timely delivery are crucial.

Water is used by humans for a variety of purposes, including drinking, industrial applications, irrigating farmland, hydroelectric power, trash disposal, and recreation. It is critical that water supplies be conserved, both for human consumption and for the health of the ecosystem. Water supplies are being depleted in many locations as a result of population expansion, pollution, and urbanization, among other factors. Climate variability and change, which have an impact on the hydrologic cycle, have exacerbated these strains even more.