Danielle Hollingshead and Christina Brown are shown here measuring stream flow on Wolfe Creek with our new Stream Pro from Teledyne RDI. The Stream Pro (which has been christened "The Wild Parsnip") is an acoustic Doppler current profiler. From the Teledyne RDI website: "An ADCP transmits sound bursts into the water column. Suspended particles carried by water currents produce echoes (from these sound bursts) which are “heard” by the ADCP. Echoes arriving later, from deeper in the water column, are assigned greater depths in the echo record. This allows the ADCP to form vertical profiles of current velocity. The ADCP senses in four directions simultaneously. Particles within the current flow moving towards the instrument exhibit different frequencies from those moving away. This is the famous Doppler shift, which enables precise measurement of current speed and direction."
Marty St. Clair is a chemistry and environmental studies professor at Coe College in Cedar Rapids, Iowa.