Atmosphere

The atmosphere is the layer of gases that surrounds the Earth. It is held in place by the Earth's gravity and is divided into several different layers based on temperature and composition.

Composition of the Atmosphere

The Earth's atmosphere is composed of several gases, with the most abundant being nitrogen (78%) and oxygen (21%). The remaining 1% includes trace gases such as argon, carbon dioxide, and water vapor.

Layers of the Atmosphere

The atmosphere is divided into five main layers: the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. Each layer has its own unique characteristics and plays a specific role in the Earth's systems.

• Troposphere: The layer closest to the Earth's surface, where weather occurs and temperature decreases with altitude.
• Stratosphere: Contains the ozone layer, which absorbs and protects against the sun's ultraviolet radiation.
• Mesosphere: The middle layer where meteors burn up upon entering the atmosphere.
• Thermosphere: The layer where the International Space Station orbits and where temperatures can reach extreme highs.
• Exosphere: The outermost layer that gradually transitions into outer space.

Functions of the Atmosphere

The atmosphere serves several important functions, including:

• Protection: The atmosphere shields the Earth from the sun's harmful radiation and regulates temperature.
• Weather and Climate: It is the primary factor in creating weather patterns and maintaining Earth's climate.
• Oxygen Supply: The atmosphere provides the oxygen necessary for respiration in living organisms.
• Carbon Cycle: It plays a role in the cycling of carbon through processes such as photosynthesis and respiration.

Study Guide

When studying the atmosphere, it is important to understand its composition, layers, and functions. Here are some key points to focus on:

1. Identify the most abundant gases in the atmosphere and their percentages.
2. Describe the characteristics and functions of each atmospheric layer.
3. Explain the importance of the atmosphere in maintaining life on Earth.
4. Discuss the impact of human activities on the atmosphere, such as air pollution and climate change.

By understanding the atmosphere and its role in the Earth's systems, we gain insight into the interconnectedness of our planet and the importance of preserving its delicate balance.

[Atmosphere] Related Worksheets and Study Guides:

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