What type of troposphere is typically found on the SOUTH side of an upper-level westerly jet?

• A. Cooler
• B. Dryer
• C. Warmer
• D. Stable

Answer: (C)

The correct choice indicates that the south side of an upper-level westerly jet is typically characterized by a warmer troposphere. This phenomenon occurs due to the general dynamics associated with jet streams and the patterns of circulation they create.

On the south side of a westerly jet, the air tends to be descending, which promotes warming as it compresses. Additionally, this area is often influenced by subtropical high-pressure systems that can lead to clear skies and warming conditions. The descending air also allows for reduced cloud formation, enhancing the heating from solar radiation.

Cirrus cloud formations frequently associated with the upper-level winds can trap heat, further contributing to the warmer temperatures near the surface. Therefore, recognizing the relationship between jet streams and temperature gradients is key to understanding why the troposphere south of the westerly jet is warmer.

The reasoning for other options can be derived from typical meteorological patterns but is not as relevant to the understanding of why the warm troposphere is observed in this scenario.