Which layer extends from the stratosphere to about 30 to 50 miles and experiences decreasing temperatures?

The layer that extends from the stratosphere to about 30 to 50 miles and experiences decreasing temperatures is the mesosphere. This layer is situated above the stratosphere and is characterized by a significant drop in temperature with increasing altitude, which differs from the stratosphere where temperatures increase with height due to the presence of the ozone layer that absorbs ultraviolet radiation.

In the mesosphere, temperatures can reach as low as -90 degrees Celsius, making it the coldest layer of the atmosphere. This temperature gradient is vital for various atmospheric phenomena, including the formation of noctilucent clouds and the burning of meteors. Understanding the structure and temperature behavior of this layer is crucial for studies related to atmospheric science and aviation.

The other options represent different atmospheric layers or regions; the stratosphere is below the mesosphere and exhibits a temperature increase with altitude, while the tropopause is the boundary between the troposphere and stratosphere, and the thermosphere is above the mesosphere where temperatures begin to increase again significantly due to solar radiation. Each of these layers has distinct characteristics that help define the overall structure of Earth’s atmosphere.