The topography and climate of South America determined its exceptional richness of surface and underground waters, the huge amount of runoff, the presence of flowing rivers of the world — the Amazon. Occupying 12% of the Earth’s land area South America receives about 2 times more (1643 mm) average rainfall per unit throughout the area. Full river flow is 27% of the total runoff of the Earth, the average runoff depth (58 cm) is also almost 2 times higher than the average value for the entire land. But the volume of flow fluctuates dramatically by mainland — from several mm to hundreds see Very unevenly distributed and the river between the basins of the oceans: the Pacific in 12 times less than the Atlantic basin (the watershed between them is mainly on the ridges of the Andes); in addition, about 10% of the territory Yu. a. refers to areas of internal drainage that crosses the continent from the Gulf of Guayaquil through the Central Andean plateau to the southern pampas. The river is dominated by rain feed, in the extreme South — also snow-glacial.
The higher layer of the medium annual flow 150-400 cm (up to 90% of precipitation) reaches in the South of Chile, due not only abundant Continue reading