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Middle Bay Lighthouse Station
Location: Middle Bay Lighthouse
Latitude: 30° 26.2' N
Longitude 88° 00.7' W
Meteorological Instrumentation
Sensor Sensor Type Range Accuracy Resolution Height
Wind Speed and Direction R.M. Young
Wind Monitor 05106-5MA
0-134 mph +/- 0.6 mph 0.1 mph 14.2 above MLLW
Air Temperature And Relative Humidity Campbell Sci.
Temperature and RH Probe HMP45AC
-40°C to +60°C 0% - 100% <+/- 0.2°C from 0°C to 60°C +/-2% from 0 to 90% +/-3% from 90 to 100% 0.1°C 1% 7.34
Photosythetically Active Radiation Li-Cor
Quantum Sensor LI-190SB
10,000 µmol/s/m2 +/- 5% 1 µE/m2/s 8.25
Barometric Pressure Vaisala
Barometer PTB101
600 to 1060 mb +/- 0.5 mb at 20ºC 0.01 mb 6.38
Precipitation Texas Electronics
Tipping Bucket Rain Guage TE-525
Up to 2 in/hour 1% at 1 in/hour or less 0.01 in 8.86
Hydrographical Instrumentation
The YSI 6600 sonde's depth is controlled by a YSI profiling winch, and as of 10/30/06, takes measurements at 3m, 2.5m, 2m, 1.5m, 1m, and 0.5m below the water’s surface once per hour, at the beginning of the hour.
Sensor Sensor Type Range Accuracy Resolution
Temperature YSI 6600
-5 to 45° C +/- 0.15° C 0.01° C
Dissolved Oxygen percent YSI 6600
ROX Optical Dissolved Oxygen
0 to 500% air saturation 0-200% air saturation, +/- 1% of the reading or 1% air saturation, whichever is greater 200-500% air saturation, +/- 15% of reading 0.1% air saturation
Dissolved Oxygen mg/L YSI 6600
ROX Optical Dissolved Oxygen
0 to 50 mg/L 0-20 mg/L, +/- 1% of the reading or 0.1 mg/L, whichever is greater 20-50 mg/L, +/- 15% of reading 0.01 mg/L
Salinity YSI 6600
Calculated from conductivity and temperature
0 to 70 ppt +/- 1.0% of reading or 0.1 ppt, whichever is greater 0.01 ppt
Vented Level YSI 6600
Stainless Steel Strain Guage
0 to 30 ft 0-10 ft = +/- .01 ft 10-30 ft = +/- .06 ft .001 ft
Turbidity YSI 6600
Optical, 90° Scatter w/ Mechanical cleaning
0-1000 NTU +/- 5% of reading or 2 NTU (whichever is greater), relative to calibration standards 0.1 NTU
Conductivity YSI 6600
4 electrode cell with autoranging
0 to 100 mS/cm +/- 0.5% of reading +0.001 mS/cm 0.001 mS/cm to 0.1 mS/cm (range dependent)
Current and Waves Sensor:
ADCP: RDInstruments Workhorse Monitor 1200kHz with NEMO waves processing module. The instrument is located on the bottom looking up 50ft East of the South Eastern most leg of the Lighthouse. It is also reporting the depth from a pressure sensor with each profile.
Currents are measured every 10 min in 36 .25m bins. Only odd bins are output to the CR1000. This setup samples to 6m of water depth to accommodate high water events. The current measurements are an average of 60 pings over the 10 min interval.
Waves are measured every 30 min. The instrument takes 2100 pings every .5 seconds (17.5min) for the waves measurements.

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