WHOTS
Woods Hole - Hawaii Ocean Time-series Site
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WHOTS Data Quality Control


Seacat/Microcat Data

The WHOTS mooring temperature and conductivity data are collected using SeaBird SBE-16 SeaCAT and SBE-37 MicroCAT instruments. Some of the MicroCATs also collect pressure data. The sampling interval varies between 150 and 600 sec depending on the instrument.

Pressure data are corrected if an offset is found between the before-deployment and after-recovery on-deck pressures. Temperature sensors are calibrated before and after deployment at SeaBird, and the data are corrected if any drift is detected during the deployment. Conductivity and temperature data are compared against CTD data from casts conducted near the WHOTS mooring during the near-monthly HOT cruises, and any data drift or offset are corrected. Details of the data processing can be found in the Data Report for the first two deployments here.

NGVM Data

The WHOTS mooring Next Generation Vector Measuring Current Meter (NGVM) data are collected using instruments provided by the Woods Hole Oceanographic Institution (WHOI). The sampling interval is 60 seconds.

Velocity components were measured relative to magnetic north and were rotated to align with true north using the local magnetic declination at the midpoint time of each deployment. Magnetic declinations were determined using NOAA's National Geophysical Data Center website: (http://www.ngdc.noaa.gov/geomagmodels/struts/calcDeclination).

The data are written to NetCDF files and contain east-west and north-south velocity components in meters per second. Velocity data were screened such that a point that exceeded four times the standard deviation of the deployment mean was replaced by an interpolated value. These wild points amounted to less than 0.2% of the data.

Meta data written into each NetCDF file for each sensor and deployment detail occasions when sensors either stopped recording data prematurely or the instrument became fouled by debris and returned bad data. These bad data were eliminated.

ADCP Data

The WHOTS mooring Acoustic Doppler Current Profiler (ADCP) data are collected using upward looking RD Instruments Workhorse 300, 600 and 1200 kHz instruments. The sampling interval is 600 seconds.

NetCDF data files include raw and quality controlled current velocities in the east, north and upward directions in meters per second. The quality control includes various criteria for data flagging.