Meeting of the Waters

The Encontro das Aguas in Brazil, or the “Meeting of the Waters,” in the Amazonas region, is one of those amazing places on Earth. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data from the NASA EO-1 team. Caption by Mike Carlowicz. Watch the video

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The Advanced Land Imager on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-color view of the confluence of the Rio Negro and Rio Solimões on June 17, 2012. At the time of the image, the water levels at Manaus, Brazil, were higher than they had been in at least a century. Manaus, the principal city of the Amazonas region, suffered record flooding in the first half of 2012.

“Six Mississippis’ worth of cafe-au-lait-colored water are converging here with two Mississippis’ worth of black-tea-colored water to produce the greatest hydrologic spectacle on the planet,” said Robert Meade, who spent decades studying rivers for the U.S. Geological Survey. “Put in terms of the sheer quantities of water, what we are seeing here is a volume of water at least a dozen times greater than the total of the water falling over the Niagara, Iguassu, and Victoria Falls combined.”

The coffee-colored water, rich with sediment, runs down from the Andes Mountains on the Rio Solimões. The black-tea water from the Colombian hills and interior jungles is nearly sediment-free and colored by decayed leaf and plant matter; it bears the name Rio Negro. Where the two rivers meet, east of Manaus, Brazil, they flow side by side within the same channel for several kilometers. The cooler, denser, and faster waters of the Solimões and the warmer, slower waters of the Negro form a boundary visible from space and from the water surface itself. Turbulent eddies and whitewater eventually mix the two, as they merge to become the Lower Amazon River.