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The Water Cycle | The Dr. Binocs Show | Learn Videos For Kids

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The water cycle, also known as the hydrological cycle, is one of Earth's most fundamental processes. It describes the continuous movement and transformation of water through our planet's oceans, atmosphere, and land. This natural system, which has operated for billions of years, plays a critical role in supporting life, shaping landscapes, and regulating global climate patterns. Through a series of interconnected stages, water changes between solid, liquid, and gas states, creating a dynamic cycle that helps distribute this essential resource across the planet.

The following article by thedailyECO explores what the water cycle is, its different stages and revealing how this fundamental process shapes Earth's climate, sustains ecosystems, and influences global water resources.

Contents

1. What is the water or hydrological cycle?

2. Characteristics of the water cycle

3. The stages of the water cycle

4. What is the importance of the water cycle?

5. Human impacts on the water cycle

The water cycle is nature's way of moving and changing water around our planet. As water travels through oceans, land, and the air above us, it transforms between three states - ice, liquid water, and water vapor - through processes like freezing, melting, evaporation, and condensation.

This continuous cycle does more than just move water around. It plays an essential role in keeping Earth's systems running by transporting water where it needs to go, storing it in different places, and naturally purifying it. Throughout this process, the total amount of water on Earth remains constant, even as it changes form and location.

Looking at how water is distributed across our planet reveals some striking patterns. Our vast oceans dominate, holding 97% of Earth's water. The remaining water is divided between ice caps and glaciers (2%), underground water sources (1%), and a surprisingly small amount (just 0.01%) in lakes, rivers, and swamps combined.

Even more remarkable is how little of this water humans can actually use. Of all the water on Earth, only 0.003% is freshwater that we can easily access from rivers, lakes, and some underground sources. The rest is either too salty, frozen in ice caps, or buried too deep underground to reach.

Understanding this uneven distribution helps explain why water conservation is so crucial. While Earth appears to have abundant water when we look at our blue planet from space, the freshwater available for human use is remarkably limited - a precious resource we must protect.

Curious about the science behind water's movement across our planet? Dive deeper into the field of hydrology in our detailed guide.

Having explained the water cycle's basic structure and distribution, let's explore its key characteristics and how they shape Earth's systems:

The cycle's defining feature is its perpetual motion, driven by the constant interaction between weather and climate patterns. Local temperatures, air pressure, and wind determine how water moves through an area. This closed system means Earth has been recycling the same water since its formation.

As water journeys between different reservoirs, it creates a complex network of connections. Rivers flow to oceans, water evaporates into clouds, and rain seeps into underground aquifers. Along these pathways, water picks up and transports essential minerals and nutrients, enriching ecosystems wherever it goes.

The sun powers the cycle, driving evaporation, while gravity pulls water back to Earth as precipitation. This interplay of energy and force not only moves water, but also helps regulate Earth's temperature and influences weather patterns.

The timeframes of this recycling vary dramatically. While a raindrop might spend just days in the atmosphere before falling as rain, water can remain frozen in glaciers for thousands of years or stay trapped underground for centuries. This temporal variation helps ensure a steady water supply across seasons and years.

Through this continuous movement, the water cycle weaves together Earth's ecosystems. From nourishing soil for plant growth to sustaining animal life, water's journey creates vital connections between environments.

The water cycle consists of seven distinct yet interconnected stages, each driven by changes in temperature, altitude, and atmospheric pressure. While these stages are part of a continuous cycle, understanding each phase helps explain how water moves through Earth's systems.

1. Evaporation: water changes from liquid to vapor as the sun heats water bodies, primarily oceans, which contribute 86% of global evaporation. This process occurs at the water's surface, where liquid water molecules gain enough energy to escape into the air.

2. Transpiration: plants release water vapor through tiny pores in their leaves, while animals contribute through respiration and sweating. This biological water release, combined with evaporation, is called evapotranspiration.

3. Condensation: as water vapor rises into cooler atmospheric layers, it condenses into tiny water droplets, forming clouds and fog. Air currents move these formations across the globe, connecting water systems worldwide.

4. Precipitation: when water droplets or ice crystals in clouds become heavy enough, they fall to Earth. Depending on temperature and atmospheric conditions, precipitation occurs as rain, snow, sleet, or hail.

5. Infiltration: some precipitation seeps into the ground through soil and rock layers. This infiltrated water replenishes underground aquifers and groundwater systems, where it can remain stored for long periods.

6. Surface runoff: water that doesn't infiltrate flows across the land's surface through streams and rivers toward larger water bodies. This runoff shapes landscapes and carries minerals and nutrients along its path.

7. Storage: water collects in various reservoirs: oceans, lakes, glaciers, and underground aquifers. Some water remains in these storage areas for long periods, while some quickly returns to the cycle through evaporation.

Additionally, deep within Earth, magmatic processes release water that eventually mingles with surface and groundwater systems, adding another dimension to this complex cycle. Want to understand the true scale of Earth's water resources? Learn the surprising statistics about our planet's water coverage in our companion guide.

The water cycle's significance extends far beyond simply moving water around our planet. As the foundation for life on Earth, this cycle connects and sustains every living system through several critical functions.

First, it serves as Earth's natural water distribution system, transporting water across continents and ecosystems without any external energy input. As water moves through the cycle, it undergoes natural purification, particularly during evaporation, which leaves behind contaminants and provides clean water essential for life.

The cycle's influence reaches into other fundamental Earth processes. It plays a crucial role in photosynthesis, where plants use water to produce oxygen and food, linking the water cycle directly to both oxygen and carbon cycles. This connection makes the water cycle essential for all oxygen-breathing organisms on Earth.

The water cycle also shapes our planet's physical features. Through erosion and mineral transport, it carves landscapes, forms soil, and moves nutrients across ecosystems. These processes create and maintain the diverse environments that support life, from rich agricultural lands to complex marine ecosystems.

Beyond supporting life directly, the water cycle helps regulate Earth's climate. Large water bodies store and release heat slowly, moderating temperature extremes. Cloud formation and precipitation patterns influence local and global climate conditions, which in turn shape ecosystem diversity and distribution. This temperature regulation is crucial for maintaining the stable conditions that allow life to thrive across our planet.

Last but not least, the cycle powers human civilization. It provides water for agriculture, enables hydroelectric power generation, and supplies industrial processes. The cycle's regular patterns have historically guided farming practices, while its stored energy drives renewable power systems.

Want to understand more about where water travels during its journey? Dive into our guide about Earth's amazing water bodies.

While the water cycle is naturally self-sustaining, human activities increasingly disrupt its delicate balance. These disruptions affect both water quality and availability across the globe.

Industrial emissions since the mid-18th century have significantly altered atmospheric conditions. Rising global temperatures increase evaporation rates, changing precipitation patterns and intensifying both floods and droughts. Additionally, when sulfur and nitrogen oxides from industrial processes combine with atmospheric moisture, they create acid rain, which damages ecosystems, infrastructure, and water quality.

Water management practices also significantly impact the cycle. The redirection of rivers and streams for agriculture, urban development, or industrial use changes natural water flow patterns. This often leads to water scarcity in some regions while creating excess in others, particularly affecting communities with limited resources. Groundwater overextraction further compounds these problems, as many aquifers are being depleted faster than they can naturally replenish.

Environmental degradation adds another layer of disruption. Soil deterioration from intensive agriculture and deforestation reduces the earth's capacity to absorb and retain water. Meanwhile, untreated wastewater from urban, industrial, and agricultural sources introduces pollutants into the cycle, affecting water quality far from the original contamination source.

These disruptions, though occurring locally, have global consequences. As water forms the foundation for all life processes, these alterations to the water cycle pose significant risks to ecosystems and human communities worldwide, highlighting the urgent need for more sustainable water management practices.

Concerned about the future of water resources? Learn about water stress and its effects on communities and ecosystems in our in-depth guide.

If you want to read similar articles to What Is the Water Cycle and Its Importance?, we recommend you visit our Meteorological phenomena category.

Camilloni, I., & Vera, C. (n.d.). The water cycle. Retrieved from http://www.bnm.me.gov.ar/giga1/documentos/EL002315.pdf

Drinking Water and Sewerage Commission. (2005). Water cycle. Retrieved from http://www.capa.gob.mx/cultura/pdfs/ciclo_agua.pdf

European Environment Agency. (2024). Water themes and data. Retrieved from https://www.eea.europa.eu/themes/water

National Aeronautics and Space Administration [NASA]. (2024). Earth Observatory: Water and climate. Retrieved from https://earthobservatory.nasa.gov/topics/water

National Center for Atmospheric Research. (2024). The water cycle. Retrieved from https://scied.ucar.edu/learning-zone/water-cycle

National Geographic. (2024). Resource library: Water cycle. Retrieved from https://education.nationalgeographic.org/resource/water-cycle/

National Oceanic and Atmospheric Administration [NOAA]. (2024). Water cycle education resources. Retrieved from https://www.noaa.gov/education/resource-collections/freshwater/water-cycle

United Nations Educational, Scientific and Cultural Organization [UNESCO]. (2024). Water security. Retrieved from https://en.unesco.org/themes/water-security

United Nations Water. (2024). Global water resources. Retrieved from https://www.unwater.org/

U.S. Geological Survey [USGS]. (2024). Water Science School. Retrieved from https://www.usgs.gov/special-topics/water-science-school

Woods Hole Oceanographic Institution. (2024). Ocean circulation and the water cycle. Retrieved from https://www.whoi.edu/know-your-ocean/ocean-topics/ocean-circulation/

World Meteorological Organization. (2024). Water resources monitoring. Retrieved from https://public.wmo.int/en/our-mandate/water

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Water Cycle Explained - Key Stages and Importance

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Discover the water cycle's stages and its crucial role on Earth. Learn how water moves through our planet, sustains life, and influences climate through this comprehensive guide.

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State where liquid turns to gas.

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State where gas turns to liquid.

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Rain, sleet, hail, or snow

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Lakes, rivers, streams, oceans

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What is the Water Cycle

Water cycle, also known as the hydrologic cycle, involves a series of stages that show the continuous movement and interchange of water between its three phases - solid, liquid, and gas, in the earth's atmosphere. The sun acts as the primary source of energy that powersthewater cycle on earth. Bernard Palissy discovered the modern theory of the water cycle in 1580 CE.

Water Cycle

Steps of the Water Cycle: How does it Work
1. Change from Liquid to Gaseous Phase - Evaporation and Transpiration
The heat of the sun causes water from the surface of water bodies such as oceans, streams, and lakes to evaporate into water vapor in the atmosphere. Plants also contribute to the water cycle when water gets evaporated from the aerial parts of the plant, such as leaves and stems by the process of transpiration.
2. Change from Solid to Gaseous Phase - Sublimation
Due to dry winds, low humidity, and low air pressure, snow present on the mountains change directly into water vapor, bypassing the liquid phase by a process known as sublimation.
3. Change from Gaseous to Liquid Phase - Condensation
The invisible water vapor formed through evaporation, transpiration, and sublimation rises through the atmosphere, while cool air rushes to take its place. This is the process of condensation that allows water vapor to transform back into liquid, which is then stored in the form of clouds.

Sometimes, a sudden drop in atmospheric temperature helps the water vapors to condense into tiny droplets of water that remain suspended in the air. These suspended water droplets get mixed with bits of dust in the air, resulting in fog.
4. Change from Gaseous to Liquid and Solid Phase - Precipitation and Deposition
Wind movements cause the water-laden cloudsto collide and fall back on the earth's surface through precipitation, simply known as rain. The water that evaporated in the first stage thus returns into different water bodies on the earth's surface, including the ocean, rivers, ponds, and lakes. In regions with extremely cold climate with sub-zero temperatures, the water vapor changes directly into frost and snow bypassing the liquid phase, causing snowfall in high altitudes by a process known as the deposition.
5. Return of the water back into the underground reserve - Runoff, Infiltration, Percolation, and Collection
The water that falls back on the earth's surface moves between the layers of soil and rocks and is accumulated as the underground water reserves known as aquifers. This process is further assisted by earthquakes, which help the underground water to reach the mantle of the earth. Some amount of precipitated water flows down the sides of mountains and hills to reach the water bodies, which again evaporates into the atmosphere. During volcanic eruptions, the underground water returns to the surface of the earth, where it mixes with the surface water bodies in order to continue the cycle.

Video: Water Cycle Explained

Why is the Water Cycle Important

The most crucial and direct impacts of the above process on earth include:

Making fresh water available to plants and animals, including humans, by purifying the groundwater on earth. During the water cycle, the water evaporates, leaving behind all the sediments and other dust particles. Similarly, for the sustenance of marine life, the saline range of all salt water bodies is kept within a certain permissible limit through infiltration.

Allowing even distribution of water on all surfaces of the earth. Water is temporarily stored as clouds in the atmosphere, whereas surface water bodies such as rivers and oceans, together with underground water, form the major permanent water reserves.

Causing a cooling effect on earth due to evaporation of water from surface water bodies, which help to form clouds that eventually precipitate down in the form of rain. This way water cycle affects the weather and climate of the earth.

Ensuring some other biogeochemical cycles, including those concerning oxygen and phosphorus, to continue in nature.

Cleaning the atmosphere by taking-away dust particles, shoot, and bacteria, thus acting as a means to purify the air we breathe.

Human Impact on Water Cycle

Human activities adversely affect the water cycle in the two following ways:

a) Deforestation: Plants play an important role in the water cycle by preventing soil erosion and thus helps to increase the groundwater level of the earth. Also, plants contribute by absorbing water from the soil, which is then released back to the atmosphere during transpiration. Deforestation adversely affects both the above processes, thus breaking the flow of the water cycle.

b) Pollution: Burning of fossil fuels acts as the major source of air pollution releasing toxic gases into the atmosphere, leading to the formation of smog and acid rain. Water from farmlands run off to the nearest water bodies carrying chemicals such as insecticides and pesticides along with them, thus causing water pollution. The presence of excessive contaminants in the atmosphere and water bodies decreases the evaporation and condensation on earth, thus adversely affecting the water cycle.

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References

Article was last reviewed on Tuesday, September 15, 2020

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Water Cycle - Definition & Steps Explained With Simple Diagram

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Water cycle, also known as the hydrologic cycle, involves a series of stages that show the continuous movement and interchange of water between its three phases - solid, liquid, and gas, in the earth's atmosphere. The sun acts as the primary source of energy that powersthewater cycle on earth.