How the Monsoon Works

A monsoon is a seasonal reversing wind bringing precipitation changes across regions like South Asia. The English word came from Portuguese monção.

Oceans stay stable because water holds 3.9 to 4.2 joules per gram per kelvin and mixes down 50 metres.

Land surfaces heat faster than oceans, creating low pressure that draws moist air inland. Rising air cools and releases rain.

The North American monsoon spreads into Arizona by mid-July. Locals call it the Desert monsoon. Desert monsoon is a very optimistic nickname.

In western Sub-Saharan Africa, the Intertropical Convergence Zone migrates northward from the equatorial Atlantic in February. It reaches western Africa near June 22.

In colder months, land cools faster than oceans. Air flows seaward, causing ocean rain. Winter monsoons tend to cause drought.

Geologists trace the monsoon's strong onset to this time.

The Himalayas block moisture-laden winds from passing into Central Asia. Central Asia remains unimpressed by their effort.