|THE LAYERS OF THE ATMOSPHERE
METEOROLOGIST JEFF HABY
The atmosphere is divided up into 4 primary layers. Below are the highlights on each layer.
Troposphere: From the surface to about 10 km aloft is the troposphere. Much of the weather
that takes places in the atmosphere occurs in this layer. On average, the temperature
decreases with height in this layer because the sun warms the surface and then that heat
is distributed upwards. It gets colder in the layer the further above the warmth of the surface.
One of the characteristics of the troposphere is how much the air mixes, thus it is
sometimes referred to as a mixing layer. Mixing occurs so easily since this layer has warm
air under cold air. Convective thermals from the surface mix the air in the layer similar
to what you would see in a lava lamp.
Stratosphere: Above the troposphere from about 10 to 50 km above the surface is the stratosphere.
This layer is very stable since the temperature increases with height in this layer. Unlike the
troposphere, the air does not mix much in this layer. The ozone layer is within the
stratosphere and this is a reason for the warming of this layer. Ozone absorbs solar
radiation and thus warms up the air. The stratosphere is one big inversion, or cap. Cold
air under warm air is a stable situation. Thunderstorms can not penetrate very far into the
stratosphere since the air is extremely stable. The air density is so low in the stratosphere
anyone that there can not be much moisture in this layer.
Mesosphere: Above the stratosphere from about 50 to 80 km above the surface is the mesosphere.
In this layer the air density is very low and the temperatures get extremely cold with
height. Temperatures get colder than -100 F toward the top of the layer. Like the troposphere, the
temperature decreases with height. The air density is so low though that no significant weather
takes place in this layer.
Thermosphere: The thermosphere extends from about 80 km above the surface and gradually
merges into outer space. In this layer the air density is so low that measuring
temperature begins to have little meaning.
Below is a diagram showing the layers of the atmosphere