Oil In Water
WET Labs was on the front line responding to the Deep Water Horizon, delivering instruments to the ships at sea and consulting with BP, NOAA and EPA. WET Labs fluorometers were used to detect the deep plume, alerting the responders that oil and gas was not just on the surface. WET Labs Senior Oceanographers spent time on board vessels working to determine how far the deep plume had spread.
The presence of both scattering and fluorescence is an excellent indicator of the existence of an oil emulsion. These sensors are effective crude oil fluorometers because crude oil has extremely broad absorption and emission spectra and the emission wavelength of the CDOM fluorometers is centered at the primary crude emission peak.
Because the CDOM fluorometer will respond to a wide range of fluorophores other than crude oil, ancillary measurements are useful to decrease false positive results. For crude oil spills in offshore "blue water" conditions such as the outer shelf and deep water of the Gulf of Mexico, CDOM fluorescent response should be quite low and high positive response in CDOM raw counts on the order of tens to hundreds of counts would indicate the presence of crude oil.
ECO CDOM Fluorometer in Action: Open Publications
Maps and Data can be found at NOAA Science Missions & Data: Deepwater Horizon, as well as specific reports—
• NOAA evaluation of CDOM fluorometer performance
• Monitoring subsurface oil using CDOM fluorometry