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.
The earth behaves like a huge magnet. It traps electrons negative charge and protons positive , concentrating them in two bands about 3, and 16, km above the globe - the Van Allen "radiation" belts. This outer region surrounding the earth, where charged particles spiral along the magnetic field lines, is called the magnetosphere. Jump to Navigation Skip to main content.
The different layers of the atmosphere The atmosphere can be divided into layers based on its temperature, as shown in the figure below. The Troposphere This is the lowest part of the atmosphere - the part we live in. The Stratosphere This extends upwards from the tropopause to about 50 km. Starting at ground level, it extends upward to about 10 km 6. We humans live in the troposphere, and nearly all weather occurs in this lowest layer. Air pressure drops, and temperatures get colder, as you climb higher in the troposphere.
The next layer up is called the stratosphere. The stratosphere extends from the top of the troposphere to about 50 km 31 miles above the ground. The infamous ozone layer is found within the stratosphere. Ozone molecules in this layer absorb high-energy ultraviolet UV light from the Sun, converting the UV energy into heat. Unlike the troposphere, the stratosphere actually gets warmer the higher you go!
That trend of rising temperatures with altitude means that air in the stratosphere lacks the turbulence and updrafts of the troposphere beneath. Commercial passenger jets fly in the lower stratosphere, partly because this less-turbulent layer provides a smoother ride. The jet stream flows near the border between the troposphere and the stratosphere. Above the stratosphere is the mesosphere.
It extends upward to a height of about 85 km 53 miles above our planet. Look up. Way up. After that, the atmosphere blends into space. Trace amounts of carbon dioxide, methane, water vapor, and neon are some of the other gases that make up the remaining 0. The atmosphere is divided into five different layers, based on temperature. The troposphere is thickest at the equator, and much thinner at the North and South Poles.
The majority of the mass of the entire atmosphere is contained in the troposphere—between approximately 75 and 80 percent. Temperatures in the troposphere decrease with altitude. It reaches from the top of the troposphere, which is called the tropopause, to an altitude of approximately 50 kilometers 30 miles.
Temperatures in the stratosphere increase with altitude. A high concentration of ozone, a molecule composed of three atoms of oxygen, makes up the ozone layer of the stratosphere. This ozone absorbs some of the incoming solar radiation, shielding life on Earth from potentially harmful ultraviolet UV light, and is responsible for the temperature increase in altitude.
The top of the stratosphere is called the stratopause. Temperatures decrease in the mesosphere with altitude. The thermosphere is located above the mesopause and reaches out to around kilometers miles.
Not much is known about the thermosphere except that temperatures increase with altitude. The uppermost layer, that blends with what is considered to be outer space, is the exosphere.
Also called a shooting star or falling star.
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