Air

This is the stable version, checked on 22 November 2022. 3 pending changes await review.

Blanketing the Earth is a thick layer of air that protects us from radiation from the Sun, falling meteors and toxic gases. This blanket, known as the atmosphere, has three layers. Without it, our Earth would be like any other planet – extremely hot or cold, pockmarked and lifeless. Three cheers for the atmosphere!

All about the Atmosphere Easy Science for Kids - Image of the Atmosphere

All about the Atmosphere Easy Science for Kids – Image of the Atmosphere

Fun Facts About the Atmosphere for Kids

There are five layers within the atmosphere. The troposphere, the stratosphere, mesosphere, ionosphere and exosphere are the layers of the atmosphere. There is not a layer called the dinosphere.

The troposphere lies closest to the Earth and is about 11 miles thick. This layer contains most of the air and oxygen in the atmosphere. Our weather is formed in the troposphere. Water evaporates from land to become rain or snow. Winds bring warm or cool weather.

The stratosphere lies above the troposphere and goes up about 30 miles high. The ozone layer is in the stratosphere. The ozone protects us from harmful rays from the Sun.

The mesosphere is the next layer, reaching 50 miles from the Earth. This layer of the atmosphere is very cold – about -180 degrees Fahrenheit. Brrrr! Here is where most meteors burn up. Without this layer, our Earth would be pocked like the Moon and other planets.

The ionosphere extends 430 miles above the Earth and is considered outer space. It is very thin and very cold. An electrical layer created by ions is found here which is used to transmit radio waves. This electrical layer also causes the Northern Lights.

High above the Earth is the exosphere, the final layer of our atmosphere. This layer extends into space. Solar winds compress it and push it down. When the winds are still, this layer can extend more than 6,000 miles into space.

The Atmosphere Vocabulary

Radiation: harmful rays

Toxic: poisonous

Pockmarked: covered with holes or bumps

Lifeless: without life

Evaporate: the process by which liquids become gases when exposed to heat

Air is one of the four classical elementsair, water, earth, and fire.

Air is mostly gas.

Air is all around us, but we can't see it. So what is air, exactly? It's a mixture of different gases. The air in Earth’s atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen. Air also has small amounts of lots of other gases, too, such as carbon dioxide, neon, and hydrogen.

This is what the air is made of.

Air pollution can ruin your outdoor plans.

edit

Air pollution is measured with the Air Quality Index, or AQI. The lower the AQI, the cleaner the air is. However, if you are outside when the AQI is over 100, it's about the same as breathing in exhaust from a car all day! Things that cause poor air quality are forest fires and cities with lots of car traffic. If the AQI is higher than 100 you shouldn't spend too much time outside.

Air can move fast and far.

edit

Even on a very still day, the air around us is always moving. But when a big wind comes, that air can really go! The fastest gust of wind ever recorded on Earth was 253 miles per hour. And as the wind picks up seeds and dust and other particles, it can carry them miles away from their original home!

There is life in the air.

edit

Lots of living things make their homes in soil and water. But did you know that living organisms can also be found hanging out in the air? These tiny microbial organisms are called bioaerosols. Although these microbes can't fly, they can travel long distances through the air—via wind, rain, or even a sneeze!

Air is a protective cushion.

edit

On Earth, we’re pretty lucky to have an atmosphere filled with air. The air in our atmosphere acts as insulation, keeping the Earth from getting too cold or too hot. Ozone, another type of gas in the air, also protects us from too much sunlight. Air in the atmosphere can also protect us from meteoroids. When meteoroids contact our atmosphere, they rub against the air and oftentimes are burned into small pieces before reaching Earth.

Air changes as you go up, up, up.

edit

Air seems light, but there is a lot of it pushing down on Earth’s surface. This is called air pressure. You experience high air pressure at sea level because the whole atmosphere is pushing down on you. The air pressure is low on top of a mountain because there is less atmosphere pushing down on you. That difference in air pressure can cause your ears to pop when you’re taking off in an airplane or driving up a hill.

Carbon dioxide in the air can be both good and bad.

edit

When humans and animals breathe, we give off an odorless gas called carbon dioxide, or CO2. Plants use this gas, along with sunlight, to make food—and oxygen too! This process is called photosynthesis. However, large amounts of CO2 are produced when cars and power plants burn coal, oil, and gasoline. This is bad because CO2is the most important contributor to human-caused global warming.

Air is important for living things.

edit

People need to breathe, and so do lots of other animals—and plants! Breathing is part of a process called respiration. During respiration, a living thing takes in oxygen from the air and gives out carbon dioxide. This process gives animals and plants the energy to eat, grow, and live life!

Air also holds water.

edit

When it's a hot, muggy summer day, you’ve probably heard the word “humid.” But what does that mean, exactly? Relative humidity is the amount of water that the air can hold before it rains. Humidity is usually measured in percentages, so the highest level of relative humidity—right before it rains—is 100 percent.

Air isn't just gas.

edit

While air is mostly gas, it also holds lots of tiny particles. These particles in the air are called aerosols. Some aerosols—like dust and pollen—are picked up naturally when the wind blows. But the air can also carry soot, smoke, and other particles from car exhaust and power plants. These are major contributors to air pollution.

 
A fan is used to move air.

Air means Earth's atmosphere. It is the clear gas we live in and breathe in. It has no color or smell.

Air is the mixture of 78.03% Nitrogen, 20.99% Oxygen, 0.94% Argon, 0.03% Carbon Dioxide, 0.01% Hydrogen, 0.00123% Neon, 0.0004% Helium, 0.00005% Krypton, 0.000006% Xenon.

We need the oxygen in the air to live. In our bodies, the lungs give oxygen to the blood, and give back carbon dioxide to the air.

The wind is moving air. Air can be polluted from gas, smoke, and ash. This pollution is one of the causes of global warming. Plants and animals also need air to live.


See also

edit