The Science Behind Monsoons

A monsoon is a large-scale seasonal shift in the region's winds caused by large differences in land and water temperatures. Monsoons in South Asia affect countries such as India, Bangladesh, and Pakistan, while the North American monsoon brings rainfall to northwestern Mexico, Arizona, and New Mexico. But how does a monsoon work? Summer monsoons form when the land is warmer than the ocean. Warm water in the ocean evaporates, causing the wind to change direction and blow moisture toward the land. This warm, moist air then condenses to become heavy rainfall that can last up to months. Monsoons can also form during the winter, when the land is cooler than the ocean. The shift in winds pulls dry air from the land toward the ocean, resulting in drier conditions. As climate change exacerbates the intensity of monsoon season, experts say wet regions will get wetter and dry regions will get drier, a shift that impacts millions around the world.