Streamflow of the Mississippi River 1931-2011

Log₁₀ of Mississippi River streamflow in meters³/second measured daily at Vicksburg MS.

Insights

The graphic shows:

• seasonal precipitation and snow melt,
• near-decadal rhythm (perhaps reflecting a solar cycle?),
• Such major events as droughts in 1940 and 1988 (which brought saltwater over 100 miles upriver) and the 1973 and 1993 floods (which damaged levees and caused hypoxic zones in the Gulf of Mexico).

Each row represents 2 years of data but is one year later than the one above it; this redundancy avoids arbitrary temporal divisions and allows us to see the 'dry' inter-year period as a whole. The USGS water year is October to September. Data are from US Geological Survey and US Army Corps of Engineers, although the current site does not show data back to 1931.