Atmosphere

The atmosphere is a layer of gases surrounding the Earth. It is held in place by the force of gravity and is composed of several different gases, with the two most abundant being nitrogen and oxygen. The atmosphere plays a critical role in supporting life on Earth by providing the air we breathe, moderating the Earth's temperature, and protecting us from the harmful effects of the sun's radiation.

Composition of the Atmosphere:

The Earth's atmosphere is made up of the following gases:

• Nitrogen (N₂) - 78%
• Oxygen (O₂) - 21%
• Argon (Ar) - 0.93%
• Carbon Dioxide (CO₂) - 0.04%
• Trace Gases (such as helium, methane, ozone, and water vapor) - 0.03%

Layers of the Atmosphere:

The atmosphere has several distinct layers, each with its own unique characteristics:

1. Troposphere - the lowest layer where weather occurs
2. Stratosphere - contains the ozone layer which absorbs UV radiation
3. Mesosphere - where most meteors burn up
4. Thermosphere - contains the ionosphere where auroras occur
5. Exosphere - the outermost layer where atmosphere gradually merges with outer space

Functions of the Atmosphere:

The atmosphere performs several important functions, including:

• Protection from harmful solar radiation
• Regulation of temperature through the greenhouse effect
• Supporting life by providing oxygen and other gases
• Weather and climate regulation

Study Guide:

To study the atmosphere, make sure to focus on the following key points:

• Composition of the atmosphere
• Layers of the atmosphere and their characteristics
• Functions of the atmosphere
• Impact of human activities on the atmosphere (e.g., air pollution, greenhouse gases)
• Relationship between the atmosphere and climate change

Understanding these concepts will provide a solid foundation for comprehending the role and importance of the Earth's atmosphere.

[Atmosphere] Related Worksheets and Study Guides:

• Earth's freshwater and atmosphereScience • Fifth Grade
• Earth's AtmosphereScience • Sixth Grade