Data from GOVARS iRobot Seaglider AUV-SG-502 released into McMurdo Sound, Southern Ross Sea, 2010-2011 (GOVARS project) (NCEI Accession 0278167)

Acquisition Description:
Latitude and longitude (parameter names lat and lon) were measured at the surface and linearly interpolated when the glider was at depth. Parameter name GPS value id indicates measurements while glider was at the surface (value = 1) or interpolated while diving (value = 0). No interpolation or smoothing was performed on other data.

Temperature and salinity (parameter names temp and sal): Temperature and salinity data were calculated using pre deployment calibration coefficients. A first-order lag correction was applied to raw measurements of temperature and conductivity (due to temperature latency). For each dive, out of range measurements and spikes (3 interquartile ranges above or below the median in windows of 15 contiguous measurements) were flagged and replaced with NaNs, which were repopulated by linear interpolation. Data were smoothed with an 11-point median filter. Parameters potemp and sigma_0 were calculated from the smoothed temp and sal datasets.

Dissolved oxygen, O2 (parameter name O2_cal): Oxygen data from the Aanderaa optode were corrected for time lags in oxygen and temperature. The resulting oxygen has an error of ±2 µmol kg-1.

Particulate backscattering coefficients, bbp (parameter names bbp470, bbp700): Backscattering digital counts were converted to at 117° by subtracting factory-provided dark counts and β multiplying by factory calibration scale factors.

Particulate organic carbon (POC) derived from bbp(700) (parameter name POC_bbp): The regression to convert ship downcast bbp at 700 nm to POC is: POC (mg C m-3) = 19607*bbp700 + 17.621; R2 = 0.85, p < 0.01. Because all backscatter sensors were cross calibrated with the ship CTD downcast, this regression was directly applied to glider bbp at 700 nm to compute glider POC.

Chlorophyll fluorescence (parameter names chl_raw): Chlorophyll fluorescence measured by glider ECOPuck BB2F was calibrated with discrete chlorophyll samples taken from calibration profiles. The regression was CHL = (FL -141)*0.00225 (R2 = 0.94, p < 0.01).