World Stamp Catalogue/British Antarctic Terr
The quantity of water released by the Amazon to the Atlantic Ocean is enormous: up to 300,000 cubic metres per second (11,000,000 cu ft/s) in the rainy season, with an average of 209,000 cubic metres per second (7,400,000 cu ft/s) from 1973 to 1990. The Amazon is responsible for about 20% of the Earth's fresh water entering the ocean. The river pushes a vast plume of fresh water into the ocean. The plume is about 400 kilometres (250 mi) long and between 100 and 200 kilometres (62 and 124 mi) wide. The fresh water, being lighter, flows on top of the seawater, diluting the salinity and altering the color of the ocean surface over an area up to 1,000,000 square miles (2,600,000 km2) in extent. For centuries ships have reported fresh water near the Amazon's mouth yet well out of sight of land in what otherwise seemed to be the open ocean.