The gliders continue to make good progress in surveying the upper region of the oil spill and along the Florida shelf. In the oil spill region there are four gliders that continue to map the area. Off Florida we currently have three gliders. Kudos to NAVO, Scipps/WHOI, iRobot/APL, USF, Mote and U Del.
Both NAVO gliders show a consistent story. The optical backscatter continues to show the highest spatial variability of any parameters and is not correlated with any of the other features mapped by the gliders. The surface waters show a shallow low salinity plume. The low salinity surface show enhanced CDOM and chlorophyll. When there is no low salinity plume present the chlorophyll maximum resides at ~50-75m. CDOM values are consistently higher at depth.
The Scripps/WHOI Spray glider continues its survey in the oil spill region. The system is heavily startified and the currents are consistently to the north west. This is consistent with the reports of oil reports that Lousiana and Mississippi are bearing the brunt of the damage. The thermocline appears to be deepening over time.
The iRobot/APL Seaglider continues its survey on the inshore side of the spill site and continues to reside in the heart of the spill zone. Data remains consistent during this high resolution survey. A stratified system, with enhanced CDOM in the mid-water depths. The chlorophyll maximum is close to ~50 meters consistent with the NAVO gliders. Chlorophyll maximum is above the mid-water CDOM maximum. Also consistent with the NAVO gliders, the optical backscatter shows a high degree of variability especially at depth. The variability is not correlated with CDOM, hydrographic features, or chlorophyll.
The Florida gliders are doing well, despite the presence of the pesky Remoras, and the UDel Blue Hen has recoveed after an “encounter” with a marine vessel late last week. The USF BASS glider is making a series of cross-shelf surveys. Like the other gliders in the northern gulf, the chlorophyll maximum resides at ~50m water depth and is associated with the pycnocline. The CDOM values are highest at depth. Optical backscatter shows the presence of “bright nepheloid layers the are not correlated with the chlorophyll.
The UDel glider is in shallow water and fighting strong southerly currents. We will try to move it north before starting the cross shelf survey. The data collected the last few days shows a strongly stratified system with a pycnocline at ~15m but it is increasing with any increase in water depth. The particles, chlorophyll and CDOM are high below the pycnocline.
Waldo carries on its along shelf survey.The pycnocline is around 20m, and like the UDel glider the chlorophyll, particles, and CDOM are highest in the waters directly below the pycnocline.