Atmosphere

Definition

The atmosphere is the layer of gases surrounding a planet, held in place by gravity. It plays a crucial role in supporting life by providing essential gases like oxygen and carbon dioxide, regulating temperature through greenhouse gases, and protecting the planet from harmful solar radiation.

5 Must Know Facts For Your Next Test

1. The atmosphere is composed of 78% nitrogen, 21% oxygen, and trace amounts of other gases, including carbon dioxide and argon.
2. Human activities, such as burning fossil fuels, have increased the levels of greenhouse gases in the atmosphere, leading to climate change.
3. The atmosphere is divided into several layers: troposphere, stratosphere, mesosphere, thermosphere, and exosphere, each with distinct characteristics.
4. The ozone layer, located within the stratosphere, plays a vital role in absorbing harmful ultraviolet radiation from the sun.
5. The movement of air masses within the atmosphere influences weather patterns and climate systems around the world.

Review Questions

• How does the atmosphere contribute to sustaining life on Earth?
  • The atmosphere sustains life on Earth by providing essential gases such as oxygen for respiration and carbon dioxide for photosynthesis. It also regulates temperature through the greenhouse effect, ensuring that the planet remains warm enough to support diverse ecosystems. Furthermore, the atmosphere protects living organisms from harmful solar radiation and helps distribute water vapor essential for precipitation.
• What are the consequences of increased greenhouse gas concentrations in the atmosphere?
  • Increased concentrations of greenhouse gases in the atmosphere lead to enhanced greenhouse effects, resulting in global warming and climate change. This can cause rising sea levels, more frequent extreme weather events, and shifts in ecosystems. The alteration of climate patterns can disrupt agricultural production, affect biodiversity, and pose significant challenges to human societies.
• Evaluate the interactions between the carbon cycle and the atmosphere regarding climate change implications.
  • The carbon cycle involves the exchange of carbon between the atmosphere, oceans, soil, and living organisms. Human activities like fossil fuel combustion add excess carbon dioxide to the atmosphere, intensifying climate change impacts. This altered balance affects weather patterns and habitats globally. Understanding these interactions is critical for developing strategies to mitigate climate change effects and promote sustainability.

Related terms

Greenhouse Effect: The process by which certain gases trap heat in the atmosphere, helping to maintain the Earth's temperature and support life.

Photosynthesis: The process by which green plants use sunlight, carbon dioxide, and water to produce glucose and oxygen, contributing to the cycling of carbon in the atmosphere.

Nitrogen Fixation: The process by which certain bacteria convert atmospheric nitrogen into ammonia, making it available for plants and playing a key role in the nitrogen cycle.