Download Atmosphere Notes - Northside Middle School

Atmosphere Notes
The atmosphere is a great weather machine in which a never ending flow of
energy from the sun causes global cycling of air and water. Our atmosphere
creates our climate and without it, we would not be able to survive.
The gases that makeup the Atmosphere.
Atmospheric Composition The gasses in the
air are well-mixed, meaning they do not vary
widely with location or time at the surface.
Water vapor (H2O) is a variable gas. You
will see it depends on temperature and
the availability of liquid water. A volume
of air can have between 0% and 4% water
vapor, and this varies both in time and
space
Vertical Layers of the Atmosphere
The Earth’s atmosphere has 4
distinct layers that are identified by
the way temperature changes with
height. These layers are:
- Troposphere
- Stratosphere
- Mesosphere
-Thermosphere
•
Troposphere - This is the layer closest to the Earth’s surface. It is the layer we all live
in.
• Almost all the weather phenomenon we know of occurs in this layer.
• Temperature on average decreases with height . Air in the troposphere is
heated from the ground up.
Stratosphere - The Stratosphere is the second layer of the atmosphere.
• The ozone layer is located in the Stratosphere.
• Airplanes fly in this layer.
• Temperature increases with height
• Very little mixing occurs between the troposphere and stratosphere. There is a
layer called the tropopause that separates the stratosphere and troposphere.
Mesosphere - The mesosphere is the next layer above the stratosphere.
• The mesosphere (literally middle sphere) is the third highest layer in our
atmosphere.
• Temperature decreases with height in the mesosphere.
• The top of the mesosphere is the coldest part of Earth's atmosphere. The
temperature there is around -90° C (-130° F)
Thermosphere - The thermosphere is the last layer.
• Most meteors from space burn up in this layer.
• Temperature increases with height in the thermosphere. The highest
temperatures for the atmosphere occur in the thermosphere, but it doesn’t feel
hot because the atmosphere is so thin up there that the heat has nothing to
“warm up”. When the sun is active, the thermosphere can heat up to 1,500°C
or higher.
• The Earth's thermosphere also includes the region of the atmosphere called
the ionosphere. The ionosphere is a region of the atmosphere that is filled with
charged particles. These are the aurora borealis.