What is the water cycle

Water is a very changeable element, and can be found in multiple ways. Water is constantly changing, going through three states: solid, liquid and gas. Water is limited, but thanks to the water cycle it can survive without ever completely disappearing. In this lesson from a TEACHER we are going to discover you What is the water cycle especially designed for children. In this way, we will try to help you understand why water never disappears. Let's start!

Water can be found in different states: solid, liquid and gaseous, but... What is the water cycle? It is important to know that water can change from one state to another, this phenomenon occurs naturally on our planet Earth and these constant changes are known as the water cycle.

Thanks to this cycle, Water moves and changes states. Water is present in the atmosphere, on the earth's surface and inside the soil; in all three places it can be found in its different states of matter.

We already told you what the water cycle is, let's discover together how this process begins in nature.

Changes in states of matter occur when thermal energy, better known as heat, is added. Let's see it with an example: when we load a pot with water and place it on the kitchen heater, if we leave it for a while we will be able to observe that the water It begins to boil and after a while steam begins to emerge, at that moment we can visualize how the water is changing state, from liquid to gaseous in the form of steam.

On planet Earth, our heat source comes from the sun. The axis of the Earth and the rotational movements of our planet in relation to the sun mean that there are two poles, one to the north and one to the south where the heat of the sun does not reach. At the poles we can find the most important reserves of solid fresh water on the planet in the form of glaciers. Since the sun is not able to heat the Earth's poles, the water there remains frozen.

On the other hand, in the rest of planet Earth, the sun works as a kitchen heater, causing the temperature to increase.

This is how the water cycle begins: the sun heats the oceans, rivers, lakes, and water courses found on the Earth's surface, causing them to evaporate. Air currents allow this vapor to rise into the atmosphere, where temperatures are minors, this causes water in the form of vapor to condense in the atmosphere, forming the well-known clouds. Clouds move around the globe due to the action of winds and air currents, when the water that stored is enough or when they collide with each other, precipitation, better known as rain or snow, is generated. On the tops of the mountains, where the temperature is cold, we can find glaciers or accumulated snow, but when they arrive In warmer seasons like spring, water in a solid state melts, circulating downwards as cold water. thaw. Both precipitation and meltwater allow water to return to the Earth's surface: to the ground, rivers and oceans. When water circulates down the earth's surface, some of it is absorbed by the soil and forms groundwater and another part runs off the surface until it reaches other water courses such as rivers, this circulation is called runoff. Water from rivers is transported by currents to the oceans. The water that circulates underground at some point springs to the surface forming lakes, or emerges through openings in the earth as freshwater springs, part of the water underground that is closest to the surface is used by plants and trees that absorb it through their roots and is returned to the atmosphere through perspiration. Another part of the groundwater forms the aquifers at great depth. Water remains in constant motion, going from one state to another.

In order to give you information about the water cycle, we must first know all the forms it can take. Water is not the same at all stages of the cycle, and can be found in three different states, which are as follows:

• Liquid: The state that we all relate to water, its shape when it is at room temperature. Liquid water is what we drink, with which we bathe, with which we get wet when it rains and which makes up rivers and seas. In this state, water occupies 75% of the planet.
• Solid: The solid state of water is ice and snow. When it starts to get hot it turns into liquid, which is what we observe when the ice melts. Water becomes solid when its temperature is less than 0º.
• Gaseous: It is water vapor. We find them, for example, in the clouds in the sky or forming fog. May form moisture in its vapor state.

Image: Online resume

In the cycle, water changes shape on numerous occasions, so to understand the water cycle you must take into account the methods that cause water to change from one form to another.

• Fusion: It is the transition from solid to liquid. When the ice or snow melts, this change of state occurs.
• Evaporation: The transition from liquid to gas. When water reaches high temperatures it evaporates, turning into water vapor.
• Condensation: Passage from gas to liquid. It is what happens when water vapor in the clouds turns into water, and falls as rain.
• Solidification: It is the transition from liquid to solid. If water cools a lot, reaching temperatures below 0º, it turns into ice, becoming a solid.

Once we understand both the states of water and the phenomena that cause it to change between forms, we can now talk about the water cycle. The water cycle consists of four phases, Which are the following:

• The Sun evaporates the water from the sea. The Sun's rays reach the Earth, and thanks to this, rivers, seas and swamps are heated.
• The water evaporates. The heat of the Sun causes the water in rivers, seas and swamps to evaporate. This also affects ice, which first melts, turning into a liquid and then evaporates, turning into a gas.
• Condensation of clouds. We have already explained that condensation is the transition from gaseous to liquid, well, the evaporated water condenses, forming clouds. Therefore, clouds are suspended water droplets that can transform into rain, hail or snow.
• Precipitation. Precipitation is the water that falls from the clouds, that is, rain. The water that has been evaporated, and that has formed the clouds, is now returned as rain to the earth. To the same place? No, since the wind causes these clouds to change their position, and therefore the water does not fall from where it rose to the sky. The water can fall into the seas, or into rivers, which will return the water to the sea. And with this the water cycle ends, which repeats itself eternally.

Therefore the water, although it is limited, does not disappear, since the water that evaporates returns to the Earth in the form of rain, and when it is evaporated again it appears again in the form of rain and so successively. That is why it is possible that you can drink the water you drink again in the future.

The set of actions that is repeated over and over again is the water cycle. We could say that water is recycled through this process, cleaning and renewing itself with each use that nature gives it.

In this other lesson from a TEACHER we discover you How is rain formed offering you a diagram of all the steps the water goes through.

Image: Hydrantia