Which atmospheric system is found just north and south of the equator where warm air rises and cold air descends?

• A. Westerlies
• B. Hadley Cells
• C. Geostrophic Winds
• D. Subtropical Highs

Answer: (B)

The Hadley Cells are a crucial component of the Earth's atmospheric circulation, specifically located just north and south of the equator. These cells are characterized by a process where warm, moist air rises near the equator due to intense solar heating. As the air rises, it cools and loses moisture, leading to cloud formation and precipitation in the tropics. Once the air reaches the upper atmosphere, it moves poleward and eventually cools down, becoming denser. This cooler air then descends around the latitudes of approximately 30 degrees north and south, creating areas of high pressure known as subtropical highs.

This mechanism plays a significant role in global weather patterns and helps to establish the trade winds that flow from these high-pressure areas back towards the equator. Understanding Hadley Cells is essential for grasping broader concepts of climate dynamics, as they influence not only precipitation patterns but also the distribution of deserts and humid regions around the globe.