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.
Geology of Chile
The Intermediate Depression, a series of faults running north to south, separates the Andes from the Coast Range with a steady decrease in altitude as the latitude increases. In Norte Grande the Intermediate Depression is partially covered by a series of salt flats, and has the world's largest potassium nitrate deposits. In Norte Chico, the depression disappears briefly before reappearing in a narrow valley at Santiago. From the narrows southward the valley widens until it is interrupted near Loncoche by the Bahía Mansa Metamorphic Complex (part of the Coast Range), then widening at Los Llanos (near Paillaco). In central and southern Chile (33°-42° south), the landscape is partially covered with glacial sediments from the Andes. In Zona Austral (south of 42° south) the depression dips below sea level, appearing occasionally in islands such as Chiloé. Its southern end is the Isthmus of Ofqui.