The Rivers of the Mississippi Watershed

The Mississippi Watershed is the largest drainage basin in North America at 3.2 million square kilometers in area. The USGS has created a database of this area which indicates the direction of waterflow at each point. By assembling these directions into streamflows, it is possible to trace the path of water from every point of the area to the mouth of the Mississippi in the Gulf of Mexico. This animation starts with the points furthest from the Gulf and reveals the streams and rivers as a steady progression towards the mouth of the Mississippi until all the major rivers are revealed. The speed of the reveal of the rivers is not dependent on the actual speed of the water flow. The reveal proceeds at a constant velocity along each river path, timed so that all reveals reach the mouth of the Mississippi at the same time. This animation does not show actual flow rates of the rivers. All rivers are shown with identical rates. The river colors and widths correspond to the relative lengths of river segments. Credit: NASA's Scientific Visualization Studio/Horace Mitchell Go here to download this video: <a href="http://svs.gsfc.nasa.gov/4493" rel="nofollow">svs.gsfc.nasa.gov/4493</a>