Question

To which category of winds ‘Chinook and Foehn winds’ belong? Why?

Answer 1

Chinook and Foehn winds belong to the category of descending or warm dry winds.

These winds occur on the leeward side of mountains. When moist air rises on the windward side of a mountain, it cools and loses moisture as precipitation. As the now dry air descends on the leeward side, it warms up rapidly due to compression (air pressure increases). This warming causes the winds to be dry and warm.

• Chinook winds blow down the eastern slopes of the Rocky Mountains in North America and are warm and dry, sometimes called “snow eaters” because they melt snow rapidly.
• Foehn winds blow down the leeward side of the Alps in Europe, causing a rapid rise in temperature and dry conditions in valleys.

Hence, both Chinook and Foehn are warm, dry winds on the leeward side of mountains caused by descending air warmed adiabatically after losing moisture on the windward side.