Chile
The diverse climate of Chile ranges from the world's driest desert in the north—the Atacama Desert—through a Mediterranean climate in the center, humid subtropical in Easter Island, to an oceanic climate, including alpine tundra and glaciers in the east and south. According to the Köppen system, Chile within its borders hosts at least ten major climatic subtypes. There are four seasons in most of the country: summer (December to February), autumn (March to May), winter (June to August), and spring (September to November).
The flora and fauna of Chile are characterized by a high degree of endemism, due to its particular geography. In continental Chile, the Atacama Desert in the north and the Andes mountains to the east are barriers that have led to the isolation of flora and fauna. Add to that the enormous length of Chile (over ) and this results in a wide range of climates and environments that can be divided into three general zones: the desert provinces of the north, central Chile, and the humid regions of the south.
Chilean Central Valley
The Central Valley (), Intermediate Depression, or Longitudinal Valley is the depression between the Chilean Coastal Range and the Andes Mountains. The Chilean Central Valley extends from the border with Peru to Puerto Montt in southern Chile, with a notable interruption at Norte Chico (27°20'–33°00' S). South of Puerto Montt the valley has a continuation as a series of marine basins up to the isthmus of Ofqui. Some of Chile's most populous cities lie within the valley including Santiago, Temuco, Rancagua, Talca and Chillán.