How Are Wind, Fog and Rain Formed?
Basics on the topic How Are Wind, Fog and Rain Formed?
Learn how wind, rain and fog are formed and what role the sun plays in creating these weather systems.
Transcript How Are Wind, Fog and Rain Formed?
This city is dark and lost. It captivates you and never let's you go. Even the weather is a mirror of this city. The icy wind, the dense fog and the heavy rain. But the big mystery is, how are wind, fog and rain formed? The icy wind makes an almost musical whistling sound. But where does the wind come from? The power of the sun plays an important role in creating wind. It heats the air. The heated air particles expand and become lighter, causing them to rise. Layers in the atmosphere, cool them again and they sink back down. The movement of the heated air particles rising, along with the cool air particles sinking, creates wind. Let's see what Wilma is doing! If the wind dies down, fog can move in silently over the streets. But how is fog formed? Have you ever walked through fog? If you have, then you know you can't see far. Fog is like a cloud on the ground. Like a cloud, the fog consists of many small drops of water, or ice crystals. Fog forms more often near bodies of water. If it is hot during the day, the water evaporates through the warmth of the sun. Water changes from a liquid to a gas during evaporation, and becomes water vapour. For example, you may have seen a puddle of rain that disappears, or evaporates, after the sun comes out. If it is cold at night, the water vapour condenses. As the warm air cools down again, the water vapour becomes water droplets. Do you know which season is often warm during the day and is very cold at night? Autumn, therefore we may see a lot of fog during this season. A rain coat protects you from the rain, so you don't get wet. But how is rain formed? Condensation plays a role in creating rain. The heated water rises as water vapour and then cools down again to form water droplets. These water droplets move back and forth in the cloud. When the small drops come together, large drops are created, which makes it difficult for them to move. When they become too heavy, they fall down to the earth as raindrops. Today we learned how wind, fog and rain are formed. We also learned that the sun plays an important role. So the big weather mystery is solved. But there is still one big question left: why is everything black and white here?
How Are Wind, Fog and Rain Formed? exercise
-
Which image shows the sun heating the air?
HintsWhich image shows heat coming from the sun?
When the sun heats the air, it rises up.
SolutionThis image shows the sun heating the air. This causes the air particles to rise.
-
Can you match each of the following weather descriptions with the appropriate weather type?
HintsThink about what kind of weather is usually associated with each description.
For example, what type of weather is typically associated with a clear, sunny sky?
Look at the list of weather types and try to match them with the descriptions based on your understanding of different weather conditions.
SolutionThe matches for the weather descriptions and weather types are:
- Clear sky, bright and sunny: sunny
- Dark clouds, heavy rain: rainy
- Thick mist, can't see far: foggy
- Strong wind, things moving around: windy
- White flakes falling, ground covered: snowy
- Grey clouds, possible rain: cloudy
-
What is a cloud on the ground?
HintsLike a cloud, the fog consists of many small drops of water, or ice crystals.
Fog forms when warm air cools down, causing water vapour in the air to turn into tiny water droplets, creating a cloud near the ground.
This often happens near water bodies and during cooler nights.
SolutionFog is described as a "cloud on the ground".
It forms more often near bodies of water, and is more common during seasons like autumn when there are warm days and cold nights.
-
How is wind formed?
HintsWhen air particles are heated, they expand.
The cool air particles sink because they are heavy.
SolutionWhen air gets heated it expands, making its particles spread out.
As the air expands, it becomes lighter because it takes up more space.
This lighter, heated air rises upward in the atmosphere.
The cool air particles sink, this creates wind.
-
What happens during evaporation?
HintsWater changes state from a liquid when it evaporates.
When the sun heats the water, it rises up as a gas.
SolutionDuring evaporation, water changes from a liquid to a gas.
-
How are raindrops formed?
HintsCondensation plays a role in creating rain by making heated water rise as water vapour.
The water droplets combine to form larger drops which become too heavy.
SolutionThe correct order is:
- Raindrops are formed when water from the ground rises up into the sky because of the sun's heat.
- In the sky, this water turns into tiny drops which join together to make bigger drops.
- When these drops get heavy, they fall down as rain.