What is a monsoon? Which way does the wind blow? In India and much of Asia, the answer determines whether the land will be wet or dry. In winter, northeasterly winds bring warm, dry air for about six months. Then, around May, the wind pattern shifts, and moist southwesterly winds from Indian Ocean cause heavy rains that drech the land. The heavy storms last six months before the dry air returns.
A monsoon, then, is a wind pattern that reverses with the seasons. There are two kinds of monsoons, dry and wet, and both can be extremely dangerous, although in very different ways.
Wet and DryDuring the wet monsoon, heavy rains sweep the land causing flooding and landslides. In parts of India, rain dumps more than 400 inches of water. Although the wet monsoon can cause much damage, people need the rains to live. Without the storms, which bring as much as 90 percent of rainfall in a year, crops would die and people would go hungry.
When the winds shift again, the dry season returns. The land becomes parched. Heat waves and droughts are common.
Too Much RainCherrapunji, India, is one of the wettest places on Earth, yet it can go months without a rainfall. During the dry monsoon season, villagers struggle to find drinkable water. Once the rainy season comes, Cherrapunji is drenched. The town averages 463 inches a year. One year, more than 900 inches of rain fell, almost all of it during the rainy season.
- Monsoon comes from the Arabic word mausim, meaning "season."
- Although monsoons are worse in Asia, other parts of the world also get these seasonal winds. Monsoons occur over large areas of land from Australia to the Caribbean Sea.