Mesosphere

Definition

The mesosphere is the layer of a planet's atmosphere located above the stratosphere and below the thermosphere, generally extending from about 50 to 85 kilometers (31 to 53 miles) above the Earth's surface. This layer is characterized by decreasing temperatures with altitude and is where most meteoroids burn up upon entering the atmosphere, making it crucial for planetary atmospheric chemistry studies.

5 Must Know Facts For Your Next Test

1. In the mesosphere, temperatures can drop as low as -90°C (-130°F), making it the coldest layer of Earth's atmosphere.
2. This layer is where most meteoroids disintegrate upon entry, creating bright streaks of light known as meteors.
3. The mesosphere plays a role in atmospheric dynamics, influencing weather patterns and stratospheric circulation.
4. Sound waves travel differently in the mesosphere due to its unique temperature gradient compared to other atmospheric layers.
5. Observations of the mesosphere are often made using radar and satellite technology due to its altitude and varying atmospheric conditions.

Review Questions

• How does the temperature change with altitude in the mesosphere, and what implications does this have for meteoroid activity?
  • In the mesosphere, temperatures decrease with altitude, reaching some of the lowest temperatures found in Earth's atmosphere at around -90°C. This significant drop in temperature affects meteoroid activity as it leads to the rapid cooling and disintegration of these objects upon entering this layer, causing them to burn up and produce visible meteors. This characteristic makes the mesosphere an essential layer for studying atmospheric chemistry related to meteoroids.
• Evaluate the importance of the mesosphere in relation to both meteorology and astrobiology.
  • The mesosphere is crucial for meteorology as it influences weather patterns and atmospheric dynamics through its unique temperature gradients. Additionally, its role in burning up meteoroids protects Earth from potential impacts. In astrobiology, understanding this layer can help scientists learn about atmospheric conditions on other planets and moons that have similar structures, thereby providing insights into their potential habitability or past geological activity.
• Synthesize information on how studying the mesosphere can contribute to our understanding of both Earth's atmosphere and extraterrestrial environments.
  • Studying the mesosphere enhances our understanding of Earth's atmospheric processes, including temperature variations and their effects on weather patterns. Moreover, insights gained from this layer can be applied to analyze atmospheres of other planets and moons, particularly those with similar atmospheric structures. This synthesis of knowledge is critical for developing models that predict atmospheric behavior under varying conditions, which can inform our understanding of climate change on Earth and atmospheric phenomena elsewhere in the solar system.

Related terms

Stratosphere: The layer of the atmosphere located above the troposphere and below the mesosphere, known for its temperature inversion and the presence of the ozone layer.

Thermosphere: The layer of the atmosphere located above the mesosphere, characterized by very high temperatures and where the ionosphere resides.

Meteoroid: A small rocky or metallic body in outer space that can enter a planet's atmosphere, often burning up in the mesosphere and creating a meteor display.