How many layers in the atmosphere

This extends upwards from the tropopause to about 50 km. It contains much of the ozone in the atmosphere. The increase in temperature with height occurs because of absorption of ultraviolet UV radiation from the sun by this ozone. Temperatures in the stratosphere are highest over the summer pole, and lowest over the winter pole. By absorbing dangerous UV radiation, the ozone in the stratosphere protects us from skin cancer and other health damage.

However chemicals called CFCs or freons, and halons which were once used in refrigerators, spray cans and fire extinguishers have reduced the amount of ozone in the stratosphere, particularly at polar latitudes, leading to the so-called "Antarctic ozone hole".

Now humans have stopped making most of the harmful CFCs we expect the ozone hole will eventually recover over the 21 st century, but this is a slow process. The region above the stratosphere is called the mesosphere. The thermosphere lies above the mesopause, and is a region in which temperatures again increase with height.

This temperature increase is caused by the absorption of energetic ultraviolet and X-Ray radiation from the sun. The region of the atmosphere above about 80 km is also caused the "ionosphere", since the energetic solar radiation knocks electrons off molecules and atoms, turning them into "ions" with a positive charge.

The temperature of the thermosphere varies between night and day and between the seasons, as do the numbers of ions and electrons which are present.

The ionosphere reflects and absorbs radio waves, allowing us to receive shortwave radio broadcasts in New Zealand from other parts of the world. The region above about km is called the exosphere. It contains mainly oxygen and hydrogen atoms, but there are so few of them that they rarely collide - they follow "ballistic" trajectories under the influence of gravity, and some of them escape right out into space. It extends upward to a height of about 85 km 53 miles above our planet. Most meteors burn up in the mesosphere.

Unlike the stratosphere, temperatures once again grow colder as you rise up through the mesosphere. The layer of very rare air above the mesosphere is called the thermosphere.

High-energy X-rays and UV radiation from the Sun are absorbed in the thermosphere, raising its temperature to hundreds or at times thousands of degrees. However, the air in this layer is so thin that it would feel freezing cold to us! In many ways, the thermosphere is more like outer space than a part of the atmosphere.

Many satellites actually orbit Earth within the thermosphere! Variations in the amount of energy coming from the Sun exert a powerful influence on both the height of the top of this layer and the temperature within it. Because of this, the top of the thermosphere can be found anywhere between and 1, km to miles above the ground. If a media asset is downloadable, a download button appears in the corner of the media viewer.

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You cannot download interactives. An atmosphere is the layers of gases surrounding a planet or other celestial body. These gases are found in layers troposphere, stratosphere, mesosphere, thermosphere, and exosphere defined by unique features such as temperature and pressure. The atmosphere protects life on earth by shielding it from incoming ultraviolet UV radiation, keeping the planet warm through insulation, and preventing extremes between day and night temperatures.

The sun heats layers of the atmosphere causing it to convect driving air movement and weather patterns around the world. Teach your students about the Earth's atmosphere with the resources in this collection. We live at the bottom of an invisible ocean called the atmosphere, a layer of gases surrounding our planet. Nitrogen and oxygen account for 99 percent of the gases in dry air, with argon, carbon dioxide, helium, neon, and other gases making up minute portions.

Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. The aurora borealis and aurora australis are sometimes seen here. The International Space Station orbits in the thermosphere. Most Earth satellites orbit in the exosphere. The Edge of Outer Space. Called INCUS, it aims to directly address why convective storms, heavy precipitation, and clouds occur exactly when and where they form.