Chile’s latitude strongly affects its deserts because the country stretches a long distance from north to south. In the north, Chile lies near the subtropical belt around 30° south, where air sinks, warms and becomes dry. This suppresses clouds and rainfall, helping create the Atacama Desert, one of the driest places on Earth.
Why northern Chile is so dry
Around 20° to 30° south, large-scale atmospheric circulation produces persistent high pressure. Air descends in this region, and descending air usually becomes warmer and less likely to form clouds. As a result, very little rain reaches northern Chile.
Latitude also affects the strength of sunlight and temperature. Northern Chile receives more direct solar energy than the south, especially during its summer, so the climate is generally warmer and more desert-like. However, the Atacama isn’t dry simply because it’s hot. Its extreme aridity results from several factors working together:
- Subtropical sinking air limits cloud formation and rainfall.
- The cold Humboldt Current cools the air along the Pacific coast and reduces evaporation, making rain-producing clouds less likely.
- The Andes Mountains block moist air arriving from the east.
- Coastal mountain ranges further separate the desert from moisture near the ocean.
Latitude changes the climate southward
As Chile extends farther south, latitude brings important changes. Temperatures generally decrease, and the influence of the subtropical high- pressure belt becomes weaker. Storms and the westerly winds of the mid- latitudes bring more rainfall, particularly to central and southern Chile. The country therefore changes gradually from desert to semi-desert, Mediterranean landscapes, temperate forests and very wet southern regions. Northern deserts give way to semi-arid areas, while central Chile, roughly between 32° and 37° south, has a Mediterranean climate with dry summers and wetter winters.
Latitude is important, but not alone
Latitude sets the broad climate pattern, but it doesn’t explain Chile’s deserts by itself. Ocean currents, atmospheric pressure, mountain ranges and elevation are equally important. In the Andes, for example, some areas remain extremely dry but can be much colder than the coastal desert because of their high altitude.
So, latitude helps place northern Chile under a dry subtropical atmosphere, while the Humboldt Current and the Andes intensify the effect. Farther south, changing latitude brings cooler temperatures and more frequent rainfall, explaining Chile’s remarkable transition from desert to rainy forests.