Table of contents | |
What is Atmosphere? | |
Weather | |
Season | |
What Changes the Weather? | |
Water | |
Evaporation | |
Condensation | |
Humid Weather | |
Water Cycle |
Air, water, and weather are interconnected elements that play crucial roles in Earth's systems.
The atmosphere is like a protective blanket of air around the Earth. It keeps us warm, gives us air to breathe, and shields us from harmful things in space.
The primary components of air are nitrogen (about 78%), oxygen (about 21%), and trace amounts of other gases such as carbon dioxide, argon, and others. It also contains water vapor, dust particles, and various pollutants.
Weather is the day-to-day condition of the atmosphere. It includes elements such as temperature, humidity, precipitation, wind speed and direction, cloud cover, and atmospheric pressure. It reflects the short-term variations in the atmosphere, typically observed over hours to days.
Different types of weather
Seasons are different times of the year when the weather and environment change in predictable ways. They happen because the Earth is tilted as it moves around the sun.
Let's see how seasons change
There are four main seasons: spring, summer, autumn (fall), and winter.
They are caused mainly by the sun. Because of the rotation of the earth, and the revolution of the earth around the sun, different areas on the earth get heated differently. An area that faces the sun directly is heated more than the area that is at the back and does not receive sun rays directly.
Revolution of Earth: Cause of Different Seasons
When the sun shines brightly, it heats the ground. The air above the ground also becomes hot. Hot air is lighter than cold air. The hot air, therefore, rises. Cold air from the surrounding areas rushes to take its place. This causes the wind to blow. The heat of the sun changes water into water vapour. The water vapour upon cooling forms clouds. When the clouds become very heavy, they fall back on earth as rain.
If you have gone to the seaside you will know that during the day, the wind blows from the sea to the land. At night, the wind blows from the land to the sea. Let us see why this happens.
Sea Breeze
Land Breeze
Around 71% of the earth’s surface is covered with water. Water is found in rivers, seas, ponds, lakes and oceans. It is also present in the form of ice and glaciers. Water is also found underground. It is also present in the air. Water changes from one state to another due to heating and cooling.
The sun heats the water on the surface of the earth and changes it into water vapour. The process of change of water into water vapour is called evaporation.It is the process by which a liquid, such as water, changes into a gas or vapor.
Evaporation depends on many other things.
The process of changing water vapour into water due to cooling is called condensation.
Water condenses and returns to the ground in several ways.
If you take a look at the plants and flowers in cold mornings, you will see tiny drops of water on them. This is dew. It is formed when the temperature is low and water vapor condenses on cool objects in the form of droplets.
Frost is formed in very cold places where the temperature at ground level is lower than 0 degree and the dew turns into ice. It causes damage to crops.
Fog and mist are formed when small droplets of water suspend in the air. Fog is denser than mist. When the visibility is less than 1 km we call it ‘fog’, but when the visibility is greater than 1 km we call it ‘mist’.
In the hot weather, you sweat a lot. When this sweat evaporates it makes you feel cool. When you sit under the fan, your sweat evaporates faster and you feel cooler. But if there is already a lot of water vapor in the air, the sweat cannot evaporate quickly. Such weather is called humid weather.
During the rainy season, the weather is often humid. Humidity refers to the amount of moisture or water vapor present in the air. The combination of rainfall and increased temperatures during the rainy season contributes to higher humidity levels.
Why do you feel very uncomfortable on a hot day during the rainy season?
Because during rainy season, it is very humid. Your sweat cannot evaporate quickly even under a fan, and you feel hot and uncomfortable.
The water present on the earth keeps on moving between lakes, rivers, oceans and the atmosphere. It is known as water cycle.
Water Cycle
So, the water cycle is a continuous process where water moves between the Earth's surface, the atmosphere, and back again.
53 videos|44 docs|59 tests
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1. What is the atmosphere and how does it affect weather? |
2. How do seasons impact weather patterns? |
3. What is the water cycle and how does it impact weather? |
4. How does evaporation contribute to changes in weather? |
5. What role does condensation play in the water cycle and weather patterns? |
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