Layers of the Earth’s Atmosphere
The atmosphere of the earth is the layer of gases (commonly called air) that surrounds the earth and creates an inhabitable environment, maintains temperature, causes weather, and protects its inhabitants from solar radiation.
How Many Layers Does the Earth’s Atmosphere Have and What are They Called
Scientists divide the atmosphere into 5 different layers based on factors like air pressure and density. The names of these layers, in order of lowest to highest, are:
Temperature: 62°F (17°C) around the lowest point to -60°F (-51°C) near the top
The troposphere is the lowest layer of the atmosphere, and it is where we live. It extends up to 8 to 14.5 km (5 to 8 miles) above the surface. It is the densest layer, containing more than half the volume of total air. Most of the atmospheric water vapor and dust is found here. This means that all the weather that we experience occurs at this level, as clouds are formed here. In the troposphere, the temperature falls as we go higher up, and is the lowest at the tropopause that acts as the boundary between this layer and the next. this is where Earth’s jet stream (a narrow, fast, winding air current) is found as well.
Temperature: -60°F (-51°C) near the tropopause to 5°F (-15°C) near the next layer
Lies just above the troposphere, extending up to 50 km (31 miles) high. It is the part of the atmosphere which contains the ozone layer, which is very important for our survival as it blocks the harmful UV rays of the Sun from reaching us. Unlike the troposphere, here the temperature increases as we go higher. Also, jet aircraft and weather balloons fly in this layer as there is less turbulence. The stratopause acts as the boundary between the stratosphere and mesosphere.
Temperature: Ranges from 32°F (0°C) to -130°F (-90°C), the lowest temperature found on Earth
The mesosphere extends from just above the stratosphere to 85 km (53 miles) high. It is the coldest layer of the atmosphere, with the temperature dropping to its lowest at the boundary between the mesosphere and thermosphere, called the mesopause. Not much is known about this layer except that meteoroids burn up here, which prevents them from reaching the Earth’s surface.
Temperature: 932°F (500°C) to 3,632°F (2,000°C) – depends on how hot the sun is
The thermosphere extends from the mesopause to about 600 km (372 miles) high. It is the hottest layer of the atmosphere, but the air density is so low that the high temperature cannot be felt at all. Most of the thermosphere is actually considered part of outer space due to this low air density. This is where the Aurora Borealis and Aurora Australis occur. They are caused by collisions between charged particles from space and the air molecules in the thermosphere and can be seen as spectacular displays of light in the sky near the north and south poles respectively.
Temperature: Up to 2,700°F (1,500°C)
The exosphere extends from the thermosphere to about 10000 km (6200 miles) and is the upper limit of the atmosphere. It is the least dense layer of the atmosphere, comprised of mostly helium and hydrogen.
Ans. The thermosphere is where satellites and space stations, like the International Space Station, orbit the Earth.
Ans. Airplanes and other commercial aircrafts fly in the troposphere.
Ans. The Kármán line, at 100 km (62 miles) above the surface, is often said to be the point at which outer space starts.
Ans. The ionosphere is a layer of charged particles (ions) that stretches from 48 km above the surface to around 965 km. It stretches over the mesosphere, most of the thermosphere, and some parts of the stratosphere. It is important for radio communications and is responsible for auroras. Its size varies with daytime and nighttime.
Article was last reviewed on Monday, May 18, 2020