Stratosphere

Definition

The stratosphere is the second layer of Earth's atmosphere, situated above the troposphere and extending from about 10 to 50 kilometers (6 to 31 miles) above sea level. This layer is characterized by a gradual increase in temperature with altitude due to the absorption of ultraviolet radiation by the ozone layer, which plays a crucial role in protecting life on Earth from harmful solar radiation.

5 Must Know Facts For Your Next Test

1. The stratosphere contains the ozone layer, which is essential for blocking harmful UV radiation from reaching Earth's surface.
2. Temperature in the stratosphere increases with altitude due to ozone absorption of UV radiation, creating a stable temperature profile that differs from the troposphere.
3. Commercial jet aircraft typically fly within the lower stratosphere to avoid turbulence found in the troposphere.
4. Weather phenomena such as storms and clouds primarily occur in the troposphere, while the stratosphere is generally stable and free from significant weather disturbances.
5. The boundary between the stratosphere and the troposphere is known as the tropopause, which acts as a cap preventing vertical mixing between these layers.

Review Questions

• How does the presence of the ozone layer within the stratosphere influence life on Earth?
  • The ozone layer in the stratosphere plays a vital role in protecting life on Earth by absorbing most of the sun's harmful ultraviolet (UV) radiation. Without this protective layer, increased UV exposure would lead to higher rates of skin cancer, cataracts, and other health issues in humans, as well as detrimental effects on ecosystems. The ozone layer also helps regulate climate patterns by influencing atmospheric circulation.
• Compare and contrast the characteristics of the troposphere and stratosphere in terms of temperature gradients and weather phenomena.
  • The troposphere and stratosphere differ significantly in their temperature gradients and weather phenomena. In the troposphere, temperature decreases with altitude, leading to unstable air and dynamic weather systems. Conversely, in the stratosphere, temperature increases with altitude due to ozone absorption of UV radiation, resulting in a more stable atmospheric layer. Weather events like storms and clouds are confined to the troposphere, while the stratosphere remains relatively calm.
• Evaluate the importance of understanding atmospheric layers like the stratosphere for addressing global environmental issues such as climate change and ozone depletion.
  • Understanding atmospheric layers like the stratosphere is crucial for addressing global environmental issues such as climate change and ozone depletion. The stratospheric ozone layer directly affects UV radiation levels at Earth's surface, impacting both human health and ecological systems. Awareness of how human activities contribute to ozone depletion informs policies aimed at protecting this vital resource. Additionally, knowledge of atmospheric dynamics enhances our ability to predict climate changes and assess their consequences on global ecosystems.

Related terms

Troposphere: The lowest layer of Earth's atmosphere, where most weather events occur and where the majority of the atmosphere's mass is found.

Ozone Layer: A region within the stratosphere that contains a high concentration of ozone (O₃) molecules, which absorb and scatter ultraviolet solar radiation.

Mesosphere: The layer of the atmosphere above the stratosphere, extending from about 50 to 85 kilometers (31 to 53 miles) in altitude, known for its decreasing temperatures with height.