glidertools.optics.par_dark_count

glidertools.optics.par_dark_count(par, depth, time, depth_percentile=90)

Calculates an in situ dark count from the PAR sensor.

The in situ dark count for the PAR sensor is calculated from the median, selecting only observations in the nighttime and in the 90th percentile of the depth sampled (i.e. the deepest depths measured)

Parameters:

  • par (numpy.ndarray or pandas.Series) – The par array after factory calibration in units uE/m2/sec.

  • depth (numpy.ndarray or pandas.Series) – The depth array in metres.

  • time (numpy.ndarray or pandas.Series) – The date & time array in a numpy.datetime64 format.

  • depth_percentile (int) – User defined percentile for minimum dark depth. Defaults to 90 so that samples from deepest 10 % of profile are used in correction

Returns:

par_dark – The par data corrected for the in situ dark value in units uE/m2/sec.

Return type:

numpy.ndarray or pandas.Series