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.
An animation of the flows along the rivers of the Mississippi watershed. 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.
This is the same animation as the previous one, except that the Missouri River is colored blue, the same as the Mississippi River. The animation starts with the reveal of a blue line at the headwaters of the Missouri River, at Brower's Spring near the Montana-Idaho border. The streamline from this point to the mouth of the Mississippi River is the longest streamline in the Mississippi watershed.
Three high resolution images of the MIssissippi watershed, one with all the rivers of the animation and the MIssississippi River in blue, and one with all the rivers of the animation and both the Mississippi and Missouri Rivers in blue, and one with no rivers indicated on the satellite image. If one of the images with rivers is laid over the image with no rivers, it is possible to identify and study the rivers on the bare satellite image of the Missippi watershed.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 22.214.171.124.0