Cold, dense air near the poles sinks and moves toward the equator, where it is heated. what happens next as air circulates? the warm air rises and moves back to the poles where it is cooled again. the air stays in place and warm the region near the equator. the air gets hot and continues rising upward in the atmosphere. the warm air gets heavier and sinks.

Cold, dense air near the poles sinks and moves toward the equator, where it is heated. After this, the warm air rises and moves back to the poles where it is cooled again.

Explanation:

In the poles, there are high-pressure zones due to the low temperature, and the cold and dense air. These high-pressure centres send winds or air to higher latitudes toward the equator. While this is happening, they get warmed as they travel and they start accumulating humidity. When they reach approximately 60 degrees latitude, they meet with warm winds that are coming from the horses' latitude (30 degrees latitude). They both ascend to the tropopause where they get cooled. As they cannot maintain humidity, it precipitates. Once done this, the winds move back to the poles, where they get cooler again, and so the cycle continues.

This cycle is known as the polar cell, and together with the Ferrell cell and the Hardley cell, they help modulate the clime.