Beacon Institute deployed B1 -- the first sensor array for the REON system -- in the Hudson River off Denning's Point in Beacon, NY (Latitude: 41° 29' 39.60” N, Longitude: 73° 59' 23.88” W) on August 20, 2008. The sensor array was redesigned in 2009 and 2010 and redeployed. It is moored with a four point tension mooring system that includes four 300 lb mushroom anchors. The shackles and chains of mooring adjust tension on the platform based on water and wind conditions, much like the way shock absorbers smooth the ride of an automobile.

PV panels provide solar power to batteries on deck, which power everything on the sensor platform including the wireless communications. The computer-controlled autonomous robotic profiler enables an array of multiple sensors to move up and down in the water for measurements.

An on-board computer receives information from the instruments and serves as a data logger, and relays commands to profilers. Remote programming allows for autonomous and cyber control of the sensor array.

 

 

(Data are presented with reference to EDT)
                                                                                                                               7-day profile 

North component Current Profile

On B1, the Acoustic Doppler Current Profiler (ADCP) points downward toward the river bed and measures the direction and speed of the water current. Dark red at the bottom of the figure shows the variation in the depth of the river bed. Depth of water column changes with time due to forces of the tide. Positive velocity magnitude (yellow to red) indicates that water is moving up the river to the north – high tide. Negative velocity magnitude (turquoise to blue) shows water moving to the south, back toward the Atlantic Ocean – low tide.

 

Particle volume

This figure shows the variation of particle concentration at the platform over time. A strong current in either direction can move water and particles from bottom, and can also bring up particles from the ocean, as concentration can change with tidal forces. Normally the particle concentration is expected to be greater at bottom of the river, and less dense at the upper portions of the water column.

Particle Volume Conc. (ul/l)

 

Chlorophyll concentration

A three-channel flurometer (FL3) is a unique instrument that provides data on the presence of biological, physical and chemical particles in the water. Chlorophyll concentration measured by FL3 provides an indirect measure of the phytoplankton biomass (algae). At certain levels, algae can be a food source, but an overabundance can be detrimental to the ecosystem. Red shows a higher concentration of phytoplankton biomass, blue is lower.