Geography, climate, and environment
A long and narrow coastal Southern Cone country on the west side of the Andes Mountains, Chile stretches over 4,300 km (2,670 mi) north to south, but only 350 km (217 mi) at its widest point east to west. This encompasses a remarkable variety of climates and landscapes. It contains 756,950 square kilometres (292,260 sq mi) of land area. It is situated within the Pacific Ring of Fire. Excluding its Pacific islands and Antarctic claim, Chile lies between latitudes 17° and 56°S, and longitudes 66° and 75°W.
Chile is among the longest north-south countries in the world. If one considers only mainland territory, Chile is unique within this group in its narrowness from east to west, with the other long north-south countries (including Brazil, Russia, Canada, and the United States, among others) all being wider from east to west by a factor of more than 10. Chile also claims 1,250,000 km2 (480,000 sq mi) of Antarctica as part of its territory (Chilean Antarctic Territory). However, this latter claim is suspended under the terms of the Antarctic Treaty, of which Chile is a signatory. It is the world's southernmost country that is geographically on the mainland.
Chile controls Easter Island and Sala y Gómez Island, the easternmost islands of Polynesia, which it incorporated to its territory in 1888, and Robinson Crusoe Island, more than 600 km (370 mi) from the mainland, in the Juan Fernández Islands. Also controlled but only temporarily inhabited (by some local fishermen) are the small islands of San Ambrosio and San Felix. These islands are notable because they extend Chile's claim to territorial waters out from its coast into the Pacific Ocean.
The northern Atacama Desert contains great mineral wealth, primarily copper and nitrates. The relatively small Central Valley, which includes Santiago, dominates the country in terms of population and agricultural resources. This area is also the historical center from which Chile expanded in the late 19th century, when it integrated the northern and southern regions. Southern Chile is rich in forests, grazing lands, and features a string of volcanoes and lakes. The southern coast is a labyrinth of fjords, inlets, canals, twisting peninsulas, and islands. The Andes Mountains are located on the eastern border.
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 4,300 km (2,672 mi)) 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.
Flora and Fauna
The native flora of Chile consists of relatively fewer species compared to the flora of other South American countries. The northernmost coastal and central region is largely barren of vegetation, approaching the most absolute desert in the world. On the slopes of the Andes, in addition to the scattered tola desert brush, grasses are found. The central valley is characterized by several species of cacti, the hardy espinos, the Chilean pine, the southern beeches and the copihue, a red bell-shaped flower that is Chile's national flower.
In southern Chile, south of the Biobío River, heavy precipitation has produced dense forests of laurels, magnolias, and various species of conifers and beeches, which become smaller and more stunted to the south. The cold temperatures and winds of the extreme south preclude heavy forestation. Grassland is found in Atlantic Chile (in Patagonia). Much of the Chilean flora is distinct from that of neighboring Argentina, indicating that the Andean barrier existed during its formation.
Some of Chile's flora has an Antarctic origin due to land bridges which formed during the Cretaceous ice ages, allowing plants to migrate from Antarctica to South America.
Just over 3,000 species of fungi are recorded in Chile, but this number is far from complete. The true total number of fungal species occurring in Chile is likely to be far higher, given the generally accepted estimate that only about 7 percent of all fungi worldwide have so far been discovered. Although the amount of available information is still very small, a first effort has been made to estimate the number of fungal species endemic to Chile, and 1995 species have been tentatively identified as possible endemics of the country.
Chile's geographical isolation has restricted the immigration of faunal life, so that only a few of the many distinctive South American animals are found. Among the larger mammals are the puma or cougar, the llama-like guanaco and the fox-like chilla. In the forest region, several types of marsupials and a small deer known as the pudu are found.
There are many species of small birds, but most of the larger common Latin American types are absent. Few freshwater fish are native, but North American trout have been successfully introduced into the Andean lakes. Owing to the vicinity of the Humboldt Current, ocean waters abound with fish and other forms of marine life, which in turn support a rich variety of waterfowl, including several penguins. Whales are abundant, and some six species of seals are found in the area.
Chile is located along a highly seismic and volcanic zone, part of the Pacific Ring of Fire, due to the subduction of the Nazca and Antarctic plates in the South American plate.
Late Paleozoic, 251 million years ago, Chile belonged to the continental block called Gondwana. It was just a depression accumulated marine sediments began to rise at the end of the Mesozoic, 66 million years ago, due to the collision between the Nazca and South American plates, resulting in the Andes. The territory would be shaped by millions of years due to the folding of the rocks, forming the current relief.
The Chilean relief consists of the central depression, which crosses the country longitudinally, flanked by two mountain ranges that make up about 80% of the territory: the Andes mountains to the east-natural border with Bolivia and Argentina in the region of Atacama and the Coastal Range west-minor height from the Andes. Chile's highest peak is the Nevado Ojos del Salado, at 6891.3 m, which is also the highest volcano in the world. The highest point of the Coastal Range is Vicuña Mackenna, at 3114 meters, located in the Sierra Vicuña Mackenna, the south of Antofagasta. Among the coastal mountains and the Pacific is a series of coastal plains, of variable length, which allow the settlement of coastal towns and big ports. Some areas of the plains territories encompass territory east of the Andes, and the Patagonian steppes and Magellan, or are high plateaus surrounded by high mountain ranges, such as the Altiplano or Puna de Atacama.
The Far North is the area between the northern boundary of the country and the parallel 26° S, covering the first three regions. It is characterized by the presence of the Atacama desert, the most arid in the world. The desert is fragmented by streams that originate in the area known as the pampas Tamarugal. The Andes, split in two and whose eastern arm runs Bolivia, has a high altitude and volcanic activity, which has allowed the formation of the Andean altiplano and salt structures as the Salar de Atacama, due to the gradual accumulation of sediments over time.
To the south is the Norte Chico, extending to the Aconcagua river. Los Andes begin to decrease its altitude to the south and closer to the coast, reaching 90 km away at the height of Illapel, the narrowest part of the Chilean territory. The two mountain ranges intersect, virtually eliminating the intermediate depression. The existence of rivers flowing through the territory allows the formation of transverse valleys, where agriculture has developed strongly in recent times, while the coastal plains begin to expand.
The Central area is the most populated region of the country. The coastal plains are wide and allow the establishment of cities and ports along the Pacific. The Andes maintains altitudes above 6000m but descend slowly starts approaching the 4000 meters on average. The intermediate depression reappears becoming a fertile valley that allows agricultural development and human settlement, due to sediment accumulation. To the south, the Cordillera de la Costa reappears in the range of Nahuelbuta while glacial sediments originate a series of lakes in the area of La Frontera.
Patagonia extends from within Reloncavi, at the height of parallel 41 ° S, to the south. During the last glaciation, this area was covered by ice that strongly eroded Chilean relief structures. As a result, the intermediate depression sinks in the sea, while the coastal mountains rise to a series of archipelagos, such as Chiloé and the Chonos, disappearing in Taitao peninsula, in the parallel 47 ° S. The Andes mountain range loses height and erosion caused by the action of glaciers has caused fjords.
East of the Andes, on the continent, or north of it, on the island of Tierra del Fuego are located relatively flat plains, which in the Strait of Magellan cover large areas.
The Andes, as he had done previously Cordillera de la Costa, begins to break in the ocean causing a myriad of islands and islets and disappear into it, sinking and reappearing in the Southern Antilles arc and then the Antarctic Peninsula, where it is called Antartandes, in the Chilean Antarctic Territory, lying between the meridians 53 ° W and 90 ° W.
In the middle of the Pacific, the country has sovereignty over several islands of volcanic origin, collectively known as Insular Chile. Of these, we highlight the archipelago of Juan Fernandez and Easter Island, which is located in the fracture zone between the Nazca plate and the Pacific plate known as East Pacific Rise.
Due to the characteristics of the territory, Chile is crossed by numerous rivers generally short in length and with low torrential flow. They commonly extend from the Andes to the Pacific Ocean, flowing in an East to West
Because of the desert, in the Norte Grande there are only short endorheic character streams, except for the river Loa, the longest in the country 440 km. In the high valleys, wetland areas generate Chungará Lake, located at 4500 meters above sea level. It and the river Lauca are shared with Bolivia, as well as the Lluta.
In the center-north of the country, the number of rivers that form valleys of agricultural importance increases. Noteworthy are the Elqui with 75 km long, 142 km Aconcagua, Maipo with 250 km and its tributary, the Mapocho with 110 km, and Maule with 240 km. Their waters mainly flow from Andean snowmelt in the summer and winter rains. The major lakes in this area are the artificial lake Rapel, the Colbun Maule lagoon and the lagoon of La Laja.