Gradients IV - Rinko profiler data set description
version 1.0 - August 2023 - Benedetto Barone
filename: gradientsIVuctd_calibrated.mat

PROCESSING STEPS:
- pressure recomputed from JFE formula
- alignment of temperature and conductivity by applying negative time lag of 0.12 s to temperature measurements
- recalculation hydrographic characteristics using Gibbs-Seawater (GSW) Oceanographic Toolbox
- calculation of depth from pressure and average latitude
- calculation of potential density anomaly with respect to 0 dbar
- choice of optode oxygen concentration computed from saturation by Garcia & Gordon (1992)
- binning on 2 m vertical levels (mean of observations, median for turbidity)
- calculation of mixed layer depth with density criterion by de Boyer Montegut et al. (2004)
- inverse filtering is applied to correct for sensor hysteresis following Bittig et al. (2014) assuming a response time of 4 s. This correction is applied only to measurements deeper than 5 m, because an initial sensor acclimation appears to take place when the sensor enters the ocean
- inverse filtering in the presence of a hypoxic layer produced a few negative values in oxygen concentration and saturation, which were reinterpolated
- Added a flag in the muctd variable for dubious (1) and very dubious (2) oxygen profiles
- Chlorophyll fluorescence is intercalibrated with the shipboard CTD (in turn calibrated against HPLC-measured chlorophyll a). This intercalibration used a linear regression for the upper 100 m.

VERSION NOTE:
v1.0: first version