All About The Water Cycle - How Does It Work?

The human body is composed of 70% water. An average human (weighing 132 lbs.) has 11 gallons of water in the body, and a negligible loss of 1.5 to 2 gallons of water can cause fatal dehydration. This reality alone indicates how vital water is to the human body. Now you can picture the number of works you do each day by the water in your body.

Even at an early age, people are known to dwell near water sources, since living far from them would likely cost them their lives. It's a necessary unit for life. Thus, water is the world's most valuable resource.

Key Facts:

About 71 percent of Earth's surface is covered with water, and about 96.5 percent of that water is in the oceans. Approximately 0.3 percent of freshwater is found in the surface water of rivers, lakes, streams, and swamps. Of all the water on Earth, more than 99 percent is unusable by humans and many other living things.
Water found at the Earth's surface can cycle quickly. However, Earth's water is in ice, seas, and underground reservoirs; it cycles gradually.
The water cycle is mind-boggling and involves state changes in water and its physical transformation within and between ecosystems.
Groundwater is found underground between soil particles and in rock cracks. Aquifers are groundwater reservoirs regularly tapped by wells.
All water in the world is subject to what is known as the water cycle, the hydrologic cycle, or the H2O cycle. The hydrological process (water cycle) underpins the existence of living beings, as they use it for drinking and survival.

**Water does matter**

Water is never static, as it is extremely valuable for living beings. We are made of water, surrounded by it, and consume and develop with it. Indeed, water is essential to life. In this way, you, like most land creatures, require a dependable supply of fresh water to survive.

The composition of seawater on Earth's surface is approximately 96 percent salt. This means there is little fresh water to sustain the ecosystem and life. Thus, insufficient water can have a profoundly negative impact on the ecosystem.

Humankind has made several advances to expand access to water. These include drilling wells to access groundwater, collecting rainwater, and using purification methods, such as salt removal, to obtain fresh water from the sea. Yet clean, safe drinking water is not generally accessible in many parts of the world today.

The vast majority of the water on Earth does not cycle—move from one place to another—quickly. Water in seas, underground, and in the form of ice tends to cycle gradually. Only surface water cycles quickly. The latter leads to acute water shortages and inadequate access to safe drinking water.

Overview of The Water Cycle

Water plays a wide role in many aspects of the Earth. Some are located at the shafts in ice caps, while others are situated in the snow and glaciers of the highest mountains.

Some are in lakes and streams, and others are underground. Some are vapors in the air. Yet, a large portion of the water on Earth is in the seas. Run and get a glass of water and put it on the table beside you. Investigate the water. Could you think about how old it is?

When the Brontosaurus strolled through lakes devouring plants, your glass of water was some dewdrops from those lakes. The same thing happened when the rulers, princesses, knights, and squires of a kingdom took a drink from their wells. Earth has a definite amount of water, and water continues to circulate. Indeed, water is always in motion.

The sun's energy drives the water cycle. It warms the sea surface and other surface waters, causing liquid water to evaporate and ice to sublime, transforming from a solid to a gas. These sun-driven processes move water into the atmosphere as water vapor.

The cycle describes how water is cycled (exchanged) through Earth's ocean, atmosphere, and land. Water always exists in all three places and in many forms: lakes and rivers, glaciers and ice sheets, oceans and seas, underground aquifers, and vapor in the air and clouds.

How Does a Water Molecule Journey?

The water cycle has neither a starting point nor an ending point. It evaporates from the Earth's surface, rises into the atmosphere, cools, and condenses into rain or snow in clouds, and falls back to the surface. When this manifestation occurs, the water cycle begins.

The water cycle, also known as the hydrologic cycle, defines the primary mechanisms of the Earth's hydrosphere. This includes all the water on, in, and around Earth.

The cycling of water in and out of the atmosphere is a crucial aspect of the Earth's weather patterns. The water cycle phases potentially encompass how water changes from liquid to solid, how it moves on the planet, and all the places it spends time along the way.

The sun's energy heats the ocean, which drives the water cycle. Some of it evaporates into the air; a relatively small amount of moisture is added as ice and snow transfer directly into vapor.

Increasing air currents take the vapor into the atmosphere, which transpires from plants and evaporates from the soil. The vapor rises into the air, where cooler temperatures cause it to condense into clouds.

The Phases of the Water Cycle

The water cycle describes the continuous movement of water on, above, and below the Earth's surface. It is also referred to as the Hydrological Cycle. The cycle describes the properties of water that cause it to move in various ways across the planet.

Water undergoes three distinct stages in the water cycle. It can be a liquid (such as water), a gas (such as water vapor), or a solid (such as ice). These three states are interchangeable: water can freeze into ice, evaporate into water vapor, and vapor can condense into water. Conversely, ice can melt into water.

The water cycle consists of several phases in which water transitions through each state.

Evaporation

Evaporation is the process by which liquid water (ocean, lake, or river) changes to a gas (water vapor). Water vapor surrounds us as an important part of the air we breathe. Water vapor is also an important greenhouse gas.

Greenhouse gases such as water vapor and carbon dioxide insulate the Earth, keeping it warm enough to support life as we know it.

The evaporation process of the water cycle is driven by the sun. As the sun interacts with liquid water on the ocean's surface, it becomes invisible gas (water vapor). Evaporation is also influenced by wind, temperature, and the density of the water body.

How important is it?

Evaporation is a vital part of the water cycle. The heat from the sun, or solar energy, drives evaporation and absorbs moisture from gardens and the largest seas and lakes. The water level will decline as it is exposed to the sun's heat.

Factors that Affect Evaporation

Some liquids evaporate more rapidly than others. Many factors influence the evaporation rate.

If the air is already congested or saturated with different substances, there won't be enough noticeable room for the liquid to evaporate rapidly. When the humidity is 100 percent, the air is saturated with water. No more water can evaporate.
Air pressure likewise influences evaporation. When air pressure is high at the surface of a waterway, the water there won't evaporate efficiently. The pressure pushing down on the water makes it difficult for the water to escape into the air as vapor. Storms are regularly high-pressure systems that avoid evaporation.
Temperature influences how rapidly evaporation happens. Boiling water will evaporate rapidly as steam.

Do plants sweat?

Sort of. People perspire (sweat), and plants transpire. Transpiration is the process by which plants lose water from their leaves. Transpiration provides evaporation, somewhat of a return of water vapor to the air.

Plant transpiration is undetectable because water evaporates from leaf surfaces. You don't simply go out and see the leaves "sweating." Just because you can't see the water doesn't mean it isn't being put into the air.

Amid a growing season, a leaf will ordinarily take in more water than its own weight. A section of cornland emits around 3,000-4,000 gallons (11,400-15,100 liters) of water daily, and a vast oak tree can consume 40,000 gallons (151,000 liters) yearly.

Transpiration

Transpiration is another important part of the water cycle, releasing water vapor from plants and soil. It normally occurs daily, releasing water vapor from the leaf's openings. This process is important in the water cycle because plants absorb moisture from the soil and release it into the atmosphere as water vapor.

Plants release water vapor through microscopic pores called stomata. The opening of the stomata is strongly influenced by light. So, it is often associated with the sun and the process of evaporation.

Evapotranspiration is the combined component of evaporation and transpiration. It is sometimes used to evaluate the movement of water in the atmosphere.

Sublimation

Sublimation describes the process by which snow and ice change directly into water vapor without first melting into liquid water. In certain climates, snow often disappears.

One way to view the sublimation results is to hang a wet shirt outside on a day with temperatures below freezing. Eventually, the ice in the shirt will disappear.

As this picture illustrates, the most effective way to visualize sublimation is not with water but with carbon dioxide. "Dry ice" is solid, frozen carbon dioxide, which sublimates or turns to gas at the temperature of -78.5 °C (-109.3°F). The fog in the picture is a mixture of cold carbon dioxide gas and cold, humid air created as the dry ice sublimates.

Sublimation occurs more readily when weather conditions are dry, such as low relative humidity and dry winds. It also occurs more often at higher altitudes, where air pressure is lower than at lower elevations.

Energy, such as strong sunlight, is also needed. Low temperatures, strong winds, intense sunlight, and very low air pressure are needed for sublimation.

Condensation

When water vapor in the air cools and changes back into liquid, forming mists or clouds, condensation occurs.

You can see a similar kind of thing at home. Set a glass of cold water on a hot day and observe what happens. Water forms outside the glass. That water didn't go some way or another; it spilled through the glass! It originated from the air.

Water vapor in the warm air transforms into liquid when it comes into contact with the cold glass.

Condensation is the process by which a gas changes into a liquid. In the water cycle, atmospheric water vapor condenses into liquid water. This process occurs in the atmosphere or at ground level.

Clouds form as water vapor condenses or becomes more concentrated (dense). Then, water vapor condenses around tiny particles called cloud condensation nuclei (CCN). CCN can be specks of dust, salt, or pollutants.

Like evaporation, condensation is also driven by the sun. As the water vapor cools, it reaches its maximum saturation point. Air pressure also significantly affects the dew point in an area.

How important is it?

Condensation is essential to the water cycle because it forms clouds. These clouds may deliver precipitation, which will be addressed later —the basic process by which water returns to Earth's surface within the water cycle. Thus, the condensation phase is the exact opposite of evaporation.

Clouds form when water vapor condenses around small particles, such as dust or smoke, which are noticeable throughout. The particles might be noticeable depending on the number of drops. Even on a clear, cloudless day, water vapor is constantly present in the atmosphere, though its amount varies.

We know it is visible on extremely humid days; it frequently feels like we have to swim through the air. Fog is a form of condensation that occurs close to the ground.

Causes of Condensation

Like evaporation, condensation happens as a major aspect of the water cycle. Ultimately, water molecules that evaporate move upward into the cooler air at higher elevations in the climate.

Water vapor in warm, moist air condenses, forming larger droplets that eventually coalesce into clouds.

The reason is the temperature adjustment. The cooler air can't keep water particles isolated, so they join again to form droplets. Condensation is happening regardless of whether clouds are visible.

As more water vapor condenses, clouds typically begin to form. Precipitation occurs, and the water cycle begins anew.

Precipitation

Precipitation occurs when so much water condenses that the air can no longer hold it. The clouds become substantial, and water falls back to Earth as rain, hail, sleet, snow, or freezing rain. Hence, precipitation is one of many ways water is cycled from the atmosphere to the Earth or the ocean.

Clouds are necessary for precipitation because raindrops are clouds with sufficiently condensed water to start falling. The cloud particles lack sufficient mass to fall. However, as condensation continues to add water to those particles, gravity, in the long run, pulls them toward the Earth as precipitation.

Around 505,000 km3 (121,000 cu mi) of water falls as precipitation yearly, 398,000 km3 (95,000 cu mi) over the oceans. The rain on land contains 107,000 km3 (26,000 cu mi) of water every year, and snow contains just 1,000 km3 (240 cu mi)

How important is it?

Precipitation is expected to replenish Earth's water supply. Without precipitation, this planet would likely be a vast desert—the number and extent of precipitation occurrences influence both water levels and water quality within an inlet.

It supplies freshwater to an estuary, an essential source of dissolved oxygen and nutrients. Droughts reduce the freshwater contribution to estuaries and lower the water levels of inland lakes. Lake levels impact water waste and flow patterns in freshwater estuaries.

How is Precipitation Measured?

Precipitation is generally described in millimeters or inches of liquid precipitation. This number is typically included over a specific timeframe, such as daily inches.

Factors that Affect Precipitation

Massive precipitation occurs near the equator and decreases with latitude expansion, such as towards the polar regions. A primary source of moisture for precipitation is evaporation from the seas. Hence, precipitation tends to be heavier close to coastlines.

Since lifting air masses are the reason for all precipitation, the amount and recurrence of rain are generally greater on the windward side of the mountain. As downslope air movement reduces humidity, the lee sides of barriers commonly experience light precipitation. Precipitation is higher at higher elevations.

Prevailing Winds: winds move moist air over land
Presence of mountains: mountain ranges can change the path of prevailing winds and impact where precipitation falls
Seasonal sea and land breezes that change direction with the seasons are known as monsoons.

Interception

Interception occurs when water movement is interrupted along various paths during overland transport. This process occurs when water is absorbed by vegetation and trees, infiltrates the ground, or is stored in puddles and landforms such as furrows and streamlets.

These waters can infiltrate the soil or return to the atmosphere through evapotranspiration or evaporation.

The most important role of this process in the water cycle is to reduce rainfall. It causes a significant amount of rainfall to be returned directly to the atmosphere, making it unavailable for infiltration. Also, interception influences the spatial distribution of infiltration. Thus, interception in the hydrological cycle is crucial.

Infiltration

Anywhere in the world, there are waterfalls. This is as rain and snow infiltrate into the subsurface soil and rock. How much infiltrates depends greatly on many factors. The infiltration of precipitation falling on the Greenland ice cap might be very small.

Infiltration is the downward movement of water from the land surface into the soil or porous rock. Some water that infiltrates will remain in the shallow soil layer, gradually moving vertically and horizontally through the soil and subsurface material.

Eventually, it might enter a stream by seepage into the stream bank. Some of the water may infiltrate deeper, recharging groundwater aquifers.

If the aquifers are shallow or sufficiently porous to allow water to move freely, people can drill wells into them and use the water for their purposes. Water may travel long distances or remain in groundwater storage before returning to the surface or seeping into other water bodies, such as streams and oceans.

In places where the water table (the top of the saturated zone) is close to the land surface and water can move through the aquifer rapidly, aquifers can be replenished artificially.

Collection

When water falls back to Earth as precipitation, it may return to the seas, lakes, or rivers, or be carried ashore by the wind. When it winds up ashore, it will either splash into the earth or turn out to be a piece of the "groundwater" that plants and creatures use to drink, or it might keep running over the dirt and gather in the seas, lakes, or streams where the cycle starts from the very beginning once more.

The Water Cycle and the Climate

The water cycle has an intense impact on Earth's climate and ecosystems. The climate refers to the total set of weather conditions in an area, evaluated over time. Humidity and temperature are two key factors that contribute to climate, primarily through the water cycle.

Humidity is considered the amount of water vapor in the air. When water vapor is not evenly distributed by the water cycle, some regions experience higher humidity than others. This occurrence adds to the completely different climates.

A region's temperature also relies on the water cycle. Through the water cycle, heat is exchanged, and temperatures change. For instance, when water evaporates, it absorbs energy and cools the local environment. Consequently, water releases energy and warms the local environment when it condenses.

How do Humans Affect the WATER CYCLE?

Water is one of the most valuable resources on Earth. With water making up at least 80 percent of living matter, the more we develop our land and expand infrastructure, the greater humankind's impact on the water cycle.

As the population grows, so do the higher living standards. People have manipulated the water supply and contaminated our limited water, and the consequences will become increasingly severe as water shortages worsen.

Additionally, the increased use of toxic chemicals in the agriculture, automotive, and manufacturing industries, as well as runoff from chemical fertilizers and pesticides, are the main factors polluting surface water and ground soil, making continued production growth impossible.

Here are a few of the general issues that disrupt the water cycle:

Urbanization: This occurs when the natural water cycle is disrupted in urban areas by buildings, concrete, and other impervious surfaces that prevent water from reaching the ground and infiltrating the soil. Keeping trees, plants, and grass healthy also begins to decline as low soil moisture impedes their healthy growth.

Deforestation occurs when all or specific trees are cleared from forest land. Deforestation occurs when builders convert this land to non-forest use. Removing trees from forests that have been growing for years reduces evapotranspiration —the sum of evaporation and plants' transpiration from land and ocean surfaces to the atmosphere.

Irrigation: As the human population has increased, demand for land has risen. People need more food to make food —and, of course, water. Irrigation is the artificial watering of land that does not receive sufficient rainfall. Irrigation is widely used in most countries.

The problem with irrigation is that it removes water from its natural source and often causes leaching and runoff where it is used. This nutrient removal leads farmers to use more fertilizers to maintain the productivity of their grasslands, while waterways become contaminated.

Other Human Activities that Change the Water Cycle Include:

Agriculture
Industry
Alteration of the chemical composition of the atmosphere
Construction of dams
Afforestation
Removal of groundwater from wells
Water abstraction from a river
Effects on climate

The water cycle is an infinite process of water circulation worldwide and throughout life. Little water has been added or lost through the ages. The water cycle prevails in all places and at all times, and humankind relies so much on this precious resource that sustains life.

Water Cycle and Climate Change: The Four Big Questions Answered

For billions of years, the Earth has been home to countless species, witnessing their birth, evolution, and extinction. Varying from microorganisms to birds, plants, and mammals is the core of their biodiversity.

Only 2.5 million years ago did humans begin to inhabit the planet. Since then, they have dominated both the Earth and other organisms. This is because they are the only species with a highly developed brain, which enables their ability to speak and engage in abstract reasoning.

Humans have learned to utilize the resources in their environment. As a result, they have industrialized, revolutionized, and modernized their operations. But every upgrade in their life becomes a downgrade in their abode.

Since the Industrial Revolution, the carbon footprint has increased. Due to industrial modernization and population growth, carbon emissions have increased, leading to air pollution and higher temperatures. If these discharges don't reduce, the gas will rise into the atmosphere, making the ozone layer thinner. Eventually, this will lead to climate change.

Climate change occurs when temperatures rise due to the burning of fossil fuels, as described by global warming. This affects weather changes, plant photosynthesis, and the water cycle. Additionally, this is caused by human activities, including the burning of plastics and emissions from cars, cigarettes, and other machinery.

As a result, biodiversity could be compromised, and the Earth's condition could become lethal.

To know more about how climate change affects the natural cycle of water, here are some questions answered:

1. Why does Climate Change increase rainfall?

Studies have concluded that 60% of the snow and rain comes from ocean moisture. Meanwhile, 40% of it came from the continents. These two sources are said to contribute to the precipitation occurring in the water cycle. An example of this is China. It gets most of its snow and rain from the waters evaporated over Eurasia.

As the temperature increases, the rate of water evaporation also increases. Like boiling water in a pot, the more intense the temperature, the faster the water evaporates.

Additionally, this phenomenon influences the intensity of rainfall and snowfall worldwide. When the world is too warm, the atmosphere could hold more moisture. Thus, it would then release the right amount of moisture it gathered when the time comes.

2. So, more precipitation falls in heavy events. Then, how is climate change contributing to more droughts?

As evaporation increases due to intense heat, the soil dries out. This results in a violent downpour, causing the topmost layer of soil to run off. The worst part is that it could cause disastrous flooding and even landslides.

As this happens, the soil will become unhealthy. This is because the soil would be dry for most seasons, causing drought or being washed away by rain.

Additionally, climate change could alter weather patterns. For example, areas that typically receive steady rainfall may experience either intense, unpredictable precipitation or little to no rainfall at all.

Moreover, glaciers and snowpacks are slowly melting due to rising temperatures, causing sea levels to rise.

3. Regarding extreme weather, what does climate change have to do with hurricanes and typhoons?

Storms, hurricanes, and typhoons intensify rapidly because they absorb more energy from warmer oceans. Since they are formed from these waters, they have a strong center of circulation, and they derive their energy from the heat of the ocean.

As a result, they bring stronger winds, more extreme rainfall, and higher storm surges along the coast. This causes damage and even loss of coastal life.

Over the last 50 years, the damage caused by disasters has increased by about 10%. This is expected to intensify in the future due to climate change. If human activities continue, the phenomenon is likely to occur sooner.

4. What does that have to do with wildfires?

Now that the precipitation is unpredictable, drought will always be around the corner. As a result, wildfires would likely occur, drying out the land, killing plant life, and rendering the area a tinderbox.

Since 1970, wildfire frequency in the western U.S. has increased by 40%. Places such as Colorado, New Mexico, Arizona, and California have experienced devastating wildfires, resulting in millions of dollars in government and community expenses due to the damage. Moreover, hundreds of plants, animals, and human lives have been lost.

It is expected that disasters will occur. It is a natural phenomenon occurring here on the planet. However, due to unregulated human activities, particularly the burning of fossil fuels, atmospheric temperatures have increased, resulting in a devastating impact on the water cycle.

Climate change is real and happening. It is now in the hands of humans: the fate of the planet. If the word about this change were spread, it would be possible to stop the damage and save the Earth.

Some scientists have already discovered cleaner energy alternatives to reduce carbon emissions. If this were implemented, the burden on the oceans, coastal communities, and areas prone to drought would be reduced, as disasters affecting them would be less devastating.

Therefore, as much as possible, people should strive to change their lifestyles and adopt cleaner ways to prevent further damage to the Earth. Moreover, they must strive to educate others and help them recognize the changes occurring now. If people open their eyes and minds to reality, saving the planet will be possible.

Learn more about the water cycle by clicking on the links below:

Water Cycle Facts

The Water Cycle

Fun Water Cycle Facts for Kids

A Summary of the Hydrologic Cycle

Earth's Water Cycle

The Water Cycle

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