Stratopause

Definition

The stratopause is the boundary layer between the stratosphere and the mesosphere in the Earth's atmosphere, occurring at altitudes of about 50 kilometers (31 miles) above sea level. It represents a significant transition point where the temperature trend reverses from increasing in the stratosphere to decreasing in the mesosphere, marking a shift in atmospheric behavior and composition.

5 Must Know Facts For Your Next Test

1. The stratopause is typically found at altitudes ranging from 50 to 55 kilometers, depending on latitude and seasonal variations.
2. Temperature at the stratopause can reach approximately -3 degrees Celsius (27 degrees Fahrenheit), which is warmer than the temperatures found in the lower mesosphere.
3. This boundary layer plays a crucial role in atmospheric dynamics, influencing weather patterns and jet streams in the stratosphere below.
4. The presence of ozone in the stratosphere contributes to the warming effect observed at the stratopause, as ozone absorbs ultraviolet radiation from the sun.
5. Understanding the stratopause is important for studying atmospheric phenomena such as stratospheric jets, tropopause variability, and climate change impacts.

Review Questions

• How does the temperature profile change at the stratopause compared to the layers immediately below and above it?
  • At the stratopause, there is a notable temperature inversion. In the stratosphere below, temperatures generally increase with altitude due to ozone absorption of UV radiation. However, at the stratopause itself, temperatures begin to decrease as one moves into the mesosphere above. This inversion is key to understanding atmospheric layering and stability.
• What role does the stratopause play in influencing weather patterns and atmospheric dynamics?
  • The stratopause serves as a pivotal boundary that separates two distinct atmospheric layers, impacting various weather patterns. It influences the behavior of jet streams in the stratosphere and plays a part in phenomena like sudden stratospheric warming. Changes or disturbances at this boundary can ripple through both layers, affecting weather conditions experienced at Earth's surface.
• Evaluate how changes in ozone concentrations within the stratosphere might affect conditions at the stratopause and their implications for climate change.
  • Changes in ozone concentrations can directly impact temperature profiles at the stratopause. Increased ozone levels typically lead to higher temperatures at this boundary due to greater absorption of UV radiation. Conversely, ozone depletion could result in lower temperatures at the stratopause. These variations can influence atmospheric circulation patterns and contribute to broader climate change effects, including altered weather patterns and potential disruptions in jet stream behaviors.

Related terms

Stratosphere:

The second major layer of Earth's atmosphere, situated above the troposphere and below the mesosphere, characterized by a temperature increase with altitude due to the absorption of ultraviolet radiation by ozone.

Mesosphere: The layer of Earth's atmosphere located above the stratosphere and below the thermosphere, where temperatures decrease with altitude and meteors burn up upon entering this layer.

Ozone Layer: A region within the stratosphere containing a high concentration of ozone (O₃), which absorbs most of the sun's harmful ultraviolet radiation, protecting living organisms on Earth.