The Water Cycle and The Three Different Types of Rainfall and Precipitation
Rain and Water
In some countries, it rains all the time and plays a major role in the growing of grass and crops. Did you ever wonder why Ireland is such a green country? This is because it rains a lot in Ireland, giving the grass plenty of water which makes it thrive. Rain is essential for life, without water and rain, we would not survive. We need rain for the growing of crops and grass and all the lakes and rivers need it. Rain is truly beautiful and it would nice to study it in more detail and how it works. In this hub, I will be explaining everything you need to know about the water cycle, about the different types of rainfall and clouds. As well as that, you will be given some wonderful, panoramic pictures to view to make this hub a truly indispensable resource.
The Water Cycle
How does water move from the rivers and streams all the way up to the sky and form as clouds? How does water move from sea to sky? These questions can be answered using the water cycle or hydrological cycle as it is more scientifically called. This cycle is the cycle that makes water move from sea to sky and sky to river. Without this we would have no streams, lakes or no rain, not even sea. Without this cycle it would not be possible for humans or animals to survive at all. Here it is.
- The cycle begins at sea. Water from the sea is warmed by the sun. This causes the seawater to evaporate. The seawater turns to water vapour and steam. The vapour rises as hot air tends to be light.
- As the water vapour rises, it is cooled. This cooling causes the water vapour to condense as cool air tends to be heavier and cannot store water droplets.
- When the vapour condenses, it forms cloud. The cloud receives more and more vapour until it cannot store any more. The cloud is saturated and so, begins to precipitate.
- Depending on temperature, precipitation has many forms. It can include rain, hailstones, sleet or snow. The most likely form is rain.
- The rain or precipitation flows into rivers and streams and these rivers and streams bring the water back to the sea where the cycle begins again.
Below is a diagram explaining the water cycle in more detail. Study it carefully and follow the route of the water.
There are three main types of rainfall which occur very frequently in the world and depend on a variety of factors. Here are the three main types of rainfall:
- Relief Rainfall
- Convectional Rainfall
- Frontal Rainfall
Did you ever wonder why there may be thundery, heavy showers on a hot, July day? Or did you ever wonder why it always rains when you live on the foot of a mountain near the sea? The three different types of rainfall I have explained below will answer all your questions.
Relief rainfall occurs very frequently near mountains beside the sea.
- Moisture-laden wind blows in from the sea. Because the wind meets a high mountain, it is forced to rise upwards. As it rises upwards, it is cooled and cloud is formed.
- The cloud becomes saturated with water vapour and it begins to precipitate on the side of the mountain facing the sea. This side of the mountain is known as the windward side.
- The cloud precipitates the most on the windward side of the mountain. By the time the cloud meets the other side, which is called the leeward side, the cloud has already lost most of its moisture so it rains very little there.
- This makes leeward sides of a mountain very sheltered from rain and they hardly ever get much rain.
- There is a more moist climate on windward sides of slopes whilst there is a more dry, sheltered climate on the leeward side.
This rainfall is very common in Hawaii, Sierra Nevada and the Andes.
You may be outside on a picnic on a hot summers day. You are enjoying yourself and you are soaking in the rays of sunshine. Suddenly, the sky gets darker and a dark, grey cumulus cloud is coming your way. Without warning, the heavens open and it begins to rain, with an almost thundery feel. Convectional rain occurs frequently on hot days usually giving cumulus cloud and thundery showers.
- The sun heats the Earth's ground. This causes the air to warm and become very hot.
- The air rises upwards. The air is then cooled and condenses to form cumulus cloud.
- When the cumulus cloud is saturated, it begins to precipitate giving heavy and thundery showers.
That is why you get thundery showers on a hot day, because the sun warms the air and it rises, cools and begins to rain.
Air mass is the same word for 'front'. That is another word to add to your weather vocabulary!
This occurs when a warm, tropical air mass comes in contact with a cold, polar air mass and is very common in Britain and Ireland.
- A warm, tropical air mass comes in contact with a cold, polar air mass. Because the air in the warm front is well, warm then it rises over the cold front.
- The air is cooled and condenses to form stratus cloud.
- When the stratus cloud becomes saturated, it begins to precipitate.