ipal river of Colombia, the Magdalena, flows north between the Cordillera Oriental and the Cordillera Central, across practically the entire country, emptying into the Caribbean near Barranquilla after a course of about 1540 km (about 960 mi). The Cauca, also an important means of communication, flows north between the Cordillera Central and the Cordillera Occidental, merging with the Magdalena about 320 km (about 200 mi) from the Caribbean. In the west the Pata cuts its way through the Andes to empty into the Pacific. The coastline of Colombia extends for about 1760 km (about 1090 mi) along the Caribbean and for about 1450 km (about 900 mi) along the Pacific. River mouths along the coasts are numerous, but no good natural harbors exist.AClimate Colombia lies almost entirely in the Torrid Zone, a meteorological term denoting the areas of the earth's surface between the tropic of Cancer and the tropic of Capricorn. The climate, however, varies with the elevation. The low regions along the coast and the deep Pata and Magdalena river valleys are torrid, with average annual temperatures of 24 to 27 C (75 to 80 F). From about 500 to 2300 m (about 1500 to 7500 ft) the climate is subtropical, and from about 2300 to 3000 m (about 7500 to 10,000 ft) it is temperate. Above about 3000 m (about 10,000 ft) is the cold-climate zone, where temperatures range from -18 to 13 C (0 to 55 F). The average January and July temperatures in Bogot are the same: 14 C (57 F). The averages for the same months in Barranquilla are 27 C (80 F) and 28 C (82 F).Throughout the year, three-month periods of rain and dry weather alternate. Along the Pacific coast precipitation is heavy. At Bogot the annual rainfall averages about 1060 mm (about 42 in), and in Barranquilla it averages about 800 mm (about 32 in). Dry weather prevails on the slopes of the Cordillera Oriental.BNatural Resources The mineral resources of the country are varied and extensive. Colombia is the majo...
