Question

A dryline generally forms between which two air masses?

1) cP and mT
2) mP and mT
3) cT and mT
4) cP and cT

Answer 1

A dryline typically forms between a cP (continental Polar) and mT (maritime Tropical) air mass, which is option 1. This boundary indicates where a colder, drier air mass meets a warmer, moist air mass, often leading to weather instabilities and thunderstorms.

Step-by-step explanation:

A dryline generally forms between two distinct air masses where there is a significant moisture difference. In the case of the options provided, the correct answer is 1) cP (continental Polar) and mT (maritime Tropical). These air masses differ significantly in terms of moisture content and temperature. The cP air mass is cold and dry, often originating from high-latitude land areas, whereas the mT air mass is warm and moist, commonly coming from oceanic areas in lower latitudes.

When these two air masses meet, the dryline represents the boundary where the dryer cP air mass meets the more humid mT air mass. This often leads to atmospheric instability, which can result in thunderstorms or severe weather, particularly when this boundary is situated over the Great Plains of the United States during spring and summer months.