Geography of Colombia
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[edit] Geographic regions
Geographers have devised different ways to divide Colombia into regions. It is most appropriate to divide the country into four geographic regions: the Andean highlands, consisting of the three Andean ranges and intervening valley lowlands; the Caribbean lowlands coastal region; the Pacific lowlands coastal region, separated from the Caribbean lowlands by swamps at the base of the Isthmus of Panama; and eastern Colombia, the great plain that lies to the east of the Andes Mountains.
[edit] Andean Highlands
Near the Ecuadorian frontier, the Andes Mountains divide into three distinct, roughly parallel chains, called cordilleras, that extend northeastward almost to the Caribbean Sea. Altitudes reach more than 5,700 meters, and mountain peaks are permanently covered with snow. The elevated basins and plateaus of these ranges have a moderate climate that provides pleasant living conditions and in many places enables farmers to harvest twice a year. Torrential rivers on the slopes of the mountains produce a large hydroelectric power potential and add their volume to the navigable rivers in the valleys. In the late 1980s, approximately 78% of the country's population lived in the Andean highlands.
The Cordillera Occidental in the west, the Cordillera Central in the center, and the Cordillera Oriental in the east have different characteristics. Geologically, the Cordillera Occidental and the Cordillera Central form the western and eastern sides of a massive crystalline arch that extends from the Caribbean lowlands to the southern border of Ecuador. The Cordillera Oriental, however, is composed of folded stratified rocks overlying a crystalline core.
The Cordillera Occidental is relatively low and is the least populated of the three cordilleras. Summits are only about 3,000 meters above sea level and do not have permanent snows. Few passes exist, although one that is about 1,520 meters above sea level provides the major city of Cali with an outlet to the Pacific Ocean. The relatively low elevation of the cordillera permits dense vegetation, which on the western slopes is truly tropical.
The Cordillera Occidental is separated from the Cordillera Central by the deep rift of the Cauca Valley. The Río Cauca rises within 200 kilometers of the border with Ecuador and flows through some of the best farmland in the country. After the two cordilleras converge, the Cauca Valley becomes a deep gorge all the way to the Caribbean lowlands.
The Cordillera Central is the loftiest of the mountain systems. Its crystalline rocks form an 800-kilometer-long towering wall dotted with snow-covered volcanoes. There are no plateaus in this range and no passes under 3,300 meters. The highest peak in this range, the Nevado del Huila, reaches 5,439 meters above sea level. The second highest peak is a volcano, Nevado del Ruiz, which erupted violently on November 13, 1985. Toward its northern end, this cordillera separates into several branches that descend toward the Caribbean coast.
Between the Cordillera Central and the Cordillera Oriental flows the Río Magdalena. This 1,600-kilometer-long river rises near a point some 180 kilometers north of the border with Ecuador, where the Cordillera Oriental and the Cordillera Central diverge. Its spacious drainage area is fed by numerous mountain torrents originating high in the snowfields. The Río Magdalena is generally navigable from the Caribbean Sea as far as the town of Neiva, deep in the interior, but is interrupted midway by rapids. The valley floor is very deep; nearly 800 kilometers from the river's mouth the elevation is no more than about 300 meters.
In the Cordillera Oriental at elevations between 2,500 and 2,700 meters, three large fertile basins and a number of small ones provide suitable areas for settlement and intensive economic production. In the basin of Cundinamarca, where the Spanish found the Chibcha Indians, the European invaders established the town of Santa Fe de Bogotá (present-day Bogotá) at an elevation of 2,650 meters above sea level.
To the north of Bogotá, in the densely populated basins of Chiquinquira and Boyacá, are fertile fields, rich mines, and large industrial establishments that produce much of the national wealth. Still farther north, where the Cordillera Oriental makes an abrupt turn to the northwest near the border with Venezuela, the highest point of this range, the Sierra Nevada de Cocuy, rises to 5,493 meters above sea level. In the department of Santander, the valleys on the western slopes are more spacious, and agriculture is intensive in the area around Bucaramanga. The northernmost region of the range around Cúcuta is so rugged that historically it has been easier to maintain communications and transportation with Venezuela than with the adjacent parts of Colombia.
[edit] Caribbean Lowlands
The Caribbean lowlands consist of all of Colombia north of an imaginary line extending northeastward from the Golfo de Urabá to the Venezuelan frontier at the northern extremity of the Cordillera Oriental. The semiarid Guajira Peninsula, in the extreme north, bears little resemblance to the rest of the region. In the southern part rises the Sierra Nevada de Santa Marta, an isolated mountain system with peaks reaching heights over 5,700 meters and slopes generally too steep for cultivation.
The Caribbean lowlands region is in roughly the shape of a triangle, the longest side of which is the coastline. Most of the country's commerce moves through Cartagena, Barranquilla, Santa Marta, and the other ports located along this important coast. Inland from these cities are swamps, hidden streams, and shallow lakes that support banana and cotton plantations, countless small farms, and, in higher places, cattle ranches.
The Caribbean region merges into and is connected with the Andean highlands through the two great river valleys. After the Andean highlands, it is the second most important region in economic activity. Approximately 17% of the country's population lived in this region in the late 1980s.
[edit] Pacific Lowlands
In the 1980s, only 3% of all Colombians resided in the Pacific lowlands, a region of jungle and swamp with considerable but little-exploited potential in minerals and other resources. Buenaventura is the only port of any size on the coast. On the east, the Pacific lowlands are bounded by the Cordillera Occidental, from which numerous streams run. Most of the streams flow westward to the Pacific, but the largest, the navigable Río Atrato, flows northward to the Golfo de Urabá, making the river settlements accessible to the major Atlantic ports and commercially related primarily to the Caribbean lowlands hinterland. To the west of the Río Atrato rises the Serranía de Baudó, an isolated chain of low mountains that occupies a large part of the region. Its highest elevation is less than 1,800 meters, and its vegetation resembles that of the surrounding tropical forest.
The Atrato Swamp--in Chocó Department adjoining the border with Panama--is a deep muck sixty-five kilometers in width that for years has challenged engineers seeking to complete the Pan American Highway. This stretch, near Turbo, where the highway is interrupted is known as the Tapón del Chocó (Chocon Plug). A second major transportation project involving Chocó Department has been proposed. A second interoceanic canal would be constructed by dredging the Río Atrato and other streams and digging short access canals. Completion of either of these projects would do much to transform this somnolent region.
[edit] Eastern Colombia
The area east of the Andes includes about 699,300 square kilometers, or three-fifths of the country's total area, but Colombians view it almost as an alien land. The entire area, known as the eastern plains, was home to only 2% of the country's population in the late 1980s. The Spanish term for plains (llanos) can be applied only to the open plains in the northern part, particularly the piedmont areas near the Cordillera Oriental, where cattle raising is practiced.
The region is unbroken by highlands except in Meta Department, where the Macarena Sierra, an outlier of the Andes, is of interest to scientists because its vegetation and wildlife are believed to be reminiscent of those that once existed throughout the Andes. Many of the numerous large rivers of eastern Colombia are navigable. The Río Guaviare and the streams to its north flow eastward and drain into the basin of the Río Orinoco, the largest river in Venezuela. Those south of the Río Guaviare flow into the basin of the Amazon. The Río Guaviare divides eastern Colombia into the llanos subregion in the north and the tropical rainforest, or selva, subregion in the south.
[edit] Climate
The striking variety in temperature and precipitation results principally from differences in elevation. Temperatures range from very hot at sea level to relatively cold at higher elevations but vary little with the season. At Bogotá, for example, the average annual temperature is 15°C, and the difference between the average of the coldest and the warmest months is less than 1°C. More significant, however, is the daily variation in temperature, from 5°C at night to 17°C during the day.
Colombians customarily describe their country in terms of the climatic zones: the area under 900 meters in elevation is called the hot zone (tierra caliente), elevations between 900 and 1,980 meters are the temperate zone (tierra templada), and elevations from 1,980 meters to about 3,500 meters constitute the cold zone (tierra fría). The upper limit of the cold zone marks the tree line and the approximate limit of human habitation. The treeless regions adjacent to the cold zone and extending to approximately 4,500 meters are high, bleak areas (usually referred to as the páramos), above which begins the area of permanent snow (nevado).
About 86% of the country's total area lies in the hot zone. Included in the hot zone and interrupting the temperate area of the Andean highlands are the long and narrow extension of the Magdalena Valley and a small extension in the Cauca Valley. Temperatures, depending on elevation, vary between 24°C and 38°C, and there are alternating dry and wet seasons corresponding to summer and winter, respectively. Breezes on the Caribbean coast, however, reduce both heat and precipitation.
Rainfall in the hot zone is heaviest in the Pacific lowlands and in parts of eastern Colombia, where rain is almost a daily occurrence and rain forests predominate. Precipitation exceeds 760 centimeters annually in most of the Pacific lowlands, making this one of the wettest regions in the world. The highest average annual precipitation in the world is estimated to be in Lloro, Colombia, with 13,299 mm (523.9 inches).[1] In eastern Colombia, it decreases from 635 centimeters in portions of the Andean piedmont to 254 centimeters eastward. Extensive areas of the Caribbean interior are permanently flooded, more because of poor drainage than because of the moderately heavy precipitation during the rainy season from May through October.
The temperate zone covers about 8% of the country. This zone includes the lower slopes of the Cordillera Oriental and the Cordillera Central and most of the intermontane valleys. The important cities of Medellín (1,487 meters) and Cali (1,030 meters) are located in this zone, where rainfall is moderate and the mean annual temperature varies between 19°C and 24°C, depending on the elevation. In the higher elevations of this zone, farmers benefit from two wet and two dry seasons each year; January through March and July through September are the dry seasons.
The cold or cool zone constitutes about 6% of the total area, including some of the most densely populated plateaus and terraces of the Colombian Andes; this zone supports about onefourth of the country's total population. The mean temperature ranges between 10°C and 19°C, and the wet seasons occur in April and May and from September to December, as in the high elevations of the temperate zone.
Precipitation is moderate to heavy in most parts of the country; the heavier rainfall occurs in the low-lying hot zone. Considerable variations occur because of local conditions that affect wind currents, however, and areas on the leeward side of the Guajira Peninsula receive generally light rainfall; the annual rainfall of thirty-five centimeters recorded at the Uribia station there is the lowest in Colombia. Considerable year-to-year variations have been recorded, and Colombia sometimes experiences droughts.
Colombia's geographic and climatic variations have combined to produce relatively well-defined "ethnocultural" groups among different regions of the country: the Costeño from the Caribbean coast; the Caucano in the Cauca region and the Pacific coast; the Antioqueño in Antioquia, Caldas, Risaralda, and Valle del Cauca departments; the Tolimense in Tolima and Huila departments; the Cundiboyacense in the interior departments of Cundinamarca and Boyacá in the Cordillera Oriental; the Santandereano in Norte de Santander and Santander departments; and the Llanero in the eastern plains. Each group has distinctive characteristics, accents, customs, social patterns, and forms of cultural adaptation to climate and topography that differentiates it from other groups. Even with rapid urbanization and modernization, regionalism and regional identification continued to be important reference points, although they were somewhat less prominent in the 1980s than in the nineteenth and early twentieth centuries.
[edit] Relief
The Andean range is located in Colombia from the southwest (Ecuador border) toward the northeast (Venezuela border) and is divided in the Colombian Massif (Macizo Colombiano) in three ranges (East Range, Centre Range and West Range) that form two long valleys, Magdalena and Cauca follow by the rivers of the same name.
The eastern half of Colombia, comprising more than half its territory, is plain and composed by savanna and rainforest, crossed by rivers belonging to the Amazon and Orinoco basins. The northern part, called "Los Llanos" is a savanna region, mostly in the Orinoco basin (therefor called also Orinoquía). The southern part is covered by the Amazon rain forest and belongs mostly to the Amazon basin. It is usually called Amazonía.
At the north and west of the Andes range there are some coastal plains. The Caribbean plains at the north and the Pacific plains at the west.
Colombian Pacific Plains are among the most rainy parts in the world, chieftly at the north (Chocó).
The highest mountain in Colombia is not in the Andes but in the Caribbean plain: Sierra Nevada de Santa Marta with its highest points named Pico Cristobal Colon (5775 m) and Pico Simon Bolivar (same elevation). Other mountains in the Caribbean plain include the María Mountains and the San Lucas Range.
In the Pacific Plains there are other mountain formations, chieftly the Darién and the Baudó Ranges.
In the eastern Region, there is the Macarena Range and there are forations belongin the Guyanas Shield.
The capital of Colombia is Bogota. The government is a republic.
[edit] Facts
Location: Northern South America, bordering the Caribbean Sea, between Panama and Venezuela, and bordering the North Pacific Ocean, between Ecuador and Panama
Geographic coordinates: 4 00 N, 72 00 W
Map references: South America
Area: total: 1,141,742 km² land: 1,058,700 km² water: 100,211 km² note: includes Malpelo Island, Roncador Cay, Serrana Bank, and Serranilla Bank
Area - comparative: slightly less than three times the size of Montana
Land boundaries: total: 6,004 km
border countries: Brazil 1,653 km, Ecuador 590 km, Panama 225 km, Peru 2,696 km (est.), Venezuela 2,850 km
Coastline: 8,208 km (Caribbean Sea 1,760 km, North Pacific Ocean 1,448 km)
Maritime claims: territorial sea: 12 nm exclusive economic zone: 200 nm continental shelf: 200-m depth or to the depth of exploitation
Climate: tropical along coast and eastern plains; cooler in highlands
Terrain: flat coastal lowlands, central highlands, high Andes Mountains, eastern lowland plains
Elevation extremes: lowest point: Pacific Ocean 0 m highest point: Pico Cristobal Colon 5,975 m note: nearby Pico Simon Bolivar also has the same elevation
Natural resources: petroleum, natural gas, coal, iron ore, nickel, gold, copper, emeralds, hydropower
Land use: arable land: 2.42% permanent crops: 1.67% other: 95.91% (2001)
Irrigated land: 8,500 km² (1998 est.)
Natural hazards: highlands subject to volcanic eruptions; occasional earthquakes; periodic droughts
Environment - current issues: deforestation; soil and water quality damage from overuse of pesticides; air pollution, especially in Bogota, from vehicle emissions
Environment - international agreements: party to: Antarctic Treaty, Biodiversity, Climate Change, Climate Change-Kyoto Protocol, Desertification, Endangered Species, Hazardous Wastes, Marine Life Conservation, Ozone Layer Protection, Ship Pollution, Tropical Timber 83, Tropical Timber 94, Wetlands signed, but not ratified: Law of the Sea
Geography - note: only South American country with coastlines on both the North Pacific Ocean and Caribbean Sea
[edit] Rivers and Lakes
Colombia has four main drainage systems: the Pacific drain, the Caribbean drain, the Orinoco Basin and the Amazon Basin.
The Orinoco and Amazon Rivers mark limits with Colombia to Venezuela and Peru respectively.
Caribbean Drain | Pacifice Drain | Orinoco Basin | Amazon Basin |
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[edit] Rivers confined to Colombia |
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[edit] Rivers originated in Colombia |
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[edit] Lakes
- Ciénaga Grande de Santa Marta
- La Cocha Lagoon
- Lake Tota
[edit] See also
[edit] References
- This article contains material from the Library of Congress Country Studies, which are United States government publications in the public domain.
- This article contains material from the CIA World Factbook which, as a U.S. government publication, is in the public domain.
[edit] Notes
- ^ Global Measured Extremes of Temperature and Precipitation. National Climatic Data Center. August 9, 2005. Last accessed January 18, 2007.
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