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Modeling Earth's Atmosphere

Author(s): Nancy P. Moreno, PhD, Barbara Z. Tharp, MS, and Judith Dresden, MS.

The Science of the Atmosphere

The air surrounding the Earth is known as the atmosphere. Earth’s gravity holds gas molecules in the atmosphere relatively close to the planet’s surface. 

Properties of Earth's Atmosphere

The atmosphere consists of layers of gases surrounding the Earth. It is mostly nitrogen (78%) and oxygen (20%). Life on Earth would not be possible without the atmosphere, which protects the surface from extremes of temperature and harmful radiation, and also provides essential water, carbon dioxide, oxygen, and nitrogen.

Each layer of the atmosphere has different characteristics.

  • Troposphere: The first layer of Earth’s atmosphere contains clouds, rain, lightning, low-flying aircraft and hot-air balloons. Much of the pollution produced by burning wood and fossil fuels remains within the troposphere, and this is where greenhouse gases are found.
  • Stratosphere: The second layer of Earth’s atmosphere contains storm clouds, wind and jet airplanes. The stratosphere contains ozone molecules that provide protection from dangerous radiation by absorbing UV light from the sun. For this reason, the stratosphere is warmer than the troposphere due to absorption of UV light by ozone in this layer.
  • Mesosphere: The third layer of Earth’s atmosphere is very cold, and contains feathery ice clouds and weather balloons. 
  • Thermosphere: The fourth layer of Earth’s atmosphere contains spacecraft, satellites and meteors. Because it absorbs some forms of radiation, parts of the thermosphere are very hot.
  • Exosphere (space outside of Earth’s atmosphere): Contains the rest of the solar system and universe.

Funded by the following grant(s)

National Institute of Environmental Health Sciences, NIH

National Institute of Environmental Health Sciences, NIH

My Health My World: National Dissemination
Grant Number: 5R25ES009259
The Environment as a Context for Opportunities in Schools
Grant Number: 5R25ES010698, R25ES06932

Houston Endowment Inc.

Foundations for the Future: Capitalizing on Technology to Promote Equity, Access and Quality in Elementary Science Education