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Water cycle primary homework help

Water cycle primary homework help

The Water Cycle (also known as the hydrologic cycle) is the journey water takes as it circulates from the land to the sky and back again.

Interactive Game
Can you put all the labels in the right places?

Why do we need the water cycle?

The Earth is covered by water, however, almost 97% is salt water found in the oceans. We can not drink salt water or use it for crops because of the salt content. We can remove salt from ocean water, but the process is very expensive.

How many processes make up the water cycle?

There are six important processes that make up the water cycle.

Condensation – the opposite of evaporation. Condensation occurs when a gas is changed into a liquid.

Infiltration – Infiltration is an important process where rain water soaks into the ground, through the soil and underlying rock layers.

Runoff – Much of the water that returns to Earth as precipitation runs off the surface of the land, and flows down hill into streams, rivers, ponds and lakes.

Evaporation – the process where a liquid, in this case water, changes from its liquid state to a gaseous state.

Precipitation – When the temperature and atmospheric pressure are right, the small droplets of water in clouds form larger droplets and precipitation occurs. The raindrops fall to Earth.

Transpiration – As plants absorb water from the soil, the water moves from the roots through the stems to the leaves. Once the water reaches the leaves, some of it evaporates from the leaves, adding to the amount of water vapor in the air. This process of evaporation through plant leaves is called transpiration.

Facts, activities, a quiz and teacher resources on the importance of clean water and its conservation.

Water for All contains classroom activities and case studies on a range of water-related issues and their impacts, using Oxfam colour photographs.

Play WaterAid’s game and see how you would help villagers build a water supply. Lots of other activites too.

The Water Cycle – Diagram to print out

Interactive Activity

The Oceans – Find out some amazing facts. Do you know why there are tides?

Water Science – Where is water produced? How pure is water? Anyone who has ever taken a drink of tap water needs to understand the science of water. Consider the chemistry of water before you pour your next glass.

Water – What is water? Why do we need it?

Water Cycle Climate

For help with a project on Rivers please visit our Geography page.

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Join Winnie the Pooh on his voyage down the River Thames. See the many picturesque villages and towns along the way from the source to the North Sea.

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Water cycle primary homework help

What is the Water Cycle?

The water cycle is a way that water moves all around the Earth. It never stops and doesn’t really have a beginning or an end. It’s like a big circle. We’ll describe it by starting with water that’s on land. For example, water that resides in the ocean or in a lake. Some water on the surface of the ocean will evaporate due to heat from the sun. When it evaporates it turns into vapor water and goes up into the atmosphere. This vapor water gets together with a lot of other vapor water and turns into clouds. Clouds move about the earth with the weather and once they are so full of water they drop the water to Earth in some form of precipitation. It could be rain, snow, sleet, or hail. When the water hits the earth it may fall right back into the ocean or feed a flower or be snow on the top of a mountain. Eventually this water will evaporate and start the whole cycle again.

How water goes from land to vapor in the atmosphere

There are three main ways that water on land turns into vapor:

Evaporation – This is the main process by which water goes from the ground to vapor in the atmosphere. Around 90 percent of the water vapor in the atmosphere got there through evaporation. Evaporation takes place only on the water’s surface. It takes energy in the form of heat. Hot water will evaporate more easily than cold water. The sun provides a lot of the energy for evaporation in the water cycle, primarily causing evaporation from the surface of the ocean.

Sublimation – This is when water moves directly to vapor from ice or snow without ever melting into water. Good conditions for sublimation to occur is when ice or snow is in very cold conditions, but it is windy and the sun is shining.

Transpiration – Transpiration is when plants release water on to their leaves that then evaporates into vapor. Plants will release a lot of water as they grow. Around 10 percent of the water vapor in the atmosphere is estimated to come from transpiration.

Water in the atmosphere

We see water in the atmosphere in the form of clouds. There is a small amount of water even in clear skies, but clouds are where water has started to condense. Condensation is the process of water vapor becoming liquid water. Condensation is a major step in the water cycle. The atmosphere helps to move water around the world. It takes water that evaporated from the ocean and moves it over land where clouds and storms form to water plants with rain.

Precipitation

Precipitation is when water falls from the atmosphere back to land. Once enough water gathers in a cloud droplets of water will form and fall to the earth. Depending on the temperature and weather this could be rain, snow, sleet, or even hail.

Water storage

A lot of the Earth’s water does not take part in the water cycle very often., Much of it is stored. The Earth stores water in a number of places. The ocean is the largest storage of water. Around 96 percent of the Earth’s water is stored in the ocean. We can’t drink the salty ocean water, so fortunately for us, freshwater is also stored in lakes, glaciers, snow caps, rivers, and below the ground in groundwater storage.