Earths Atmosphere

Peyton Mathews

Mrs. Troester

English 8- Expository Essay

7 April 2017

Earth’s Atmosphere

            For years, people have been studying the Earth’s atmosphere. Today, there are five layers in the Earth’s atmosphere. How did people find out about the layers? By breaking the five parts of earth’s atmosphere into categories and explaining them. In this essay, the five parts will be grouped together; these three groups are the troposphere and the stratosphere, mesosphere and thermosphere, and the exosphere.

            To begin, the troposphere and the stratosphere are the closest layers to us. This means that if we went straight up into the air we would go through the troposphere and the mesosphere before any other one. We live in the troposphere. The troposphere is 75% atmospheric and 99% water vapor. It extends from earth’s surface to about 20 km. The stratosphere is the second layer up. It is right about the troposphere and right below the mesosphere. It is 50 km about earth’s surface.
            Next, the mesosphere and the thermosphere are the middle layers to us. It goes the mesosphere and then the thermosphere. The mesosphere is right about the stratosphere and the thermosphere is right above the mesosphere. The mesosphere is 85 km about earth’s surface, and the thermosphere is between 85 km and 500 km above earth.

            Last, the exosphere is the farthest and the highest from us. It is at least 500 km from the earth. The air in the exosphere is very thin and is made up of mostly helium and hydrogen. So we would not be able to breathe up there.

            These three groups are the troposphere and the stratosphere, mesosphere and thermosphere, and the exosphere. I hope you learned more about our Earth’s Atmosphere. I know I sure did.