Chlorophyll (Chl) a profiles obtained with vertical in situ fluorescence measurements on an ecosystem cruise to Kong Håkon VII Hav, Southern Ocean, in March 2019 with the R/V Kronprins Haakon.
Quality
In situ Chl a fluorescence was measured with a WETLabs ECO fluorometer, bin-averaged to 1 m bins, corrected for baseline shifts (certain stations; the difference between the mode value of the station in question and the global dataset mode was added) and calibrated (fitted linearly) with the help of the determined dark value (the mode of values below 500 m) and concurrent Chl a values from water samples. The upcast values (median of a 2 m window around the water sampling depth) were used for the calibration as water sampling happened during the upcast, whereas downcast values are included in this dataset (both as mat and netCDF file) as the water column is less disturbed during the downcast. R2 of the fit was 0.74 and 0.67 before and after a sensitivity setting change (data treated separately), respectively. Please note that the data are not corrected for non-photochemical fluorescence quenching (NPQ). CO2 (https://doi.org/10.4319/lom.2012.10.483) data.
Mat file variable explanations: chla: Chlorophyll a concentration in mg/m3 depth: sampling (measurement) depth in meter lat: latitude in degrees south lon: longitude in degrees east sampling_time: the different columns contain the year, month, day, hour and minute of the sampling time station_number: CTD station running number starting with number 52
=== In this dataset there are also included mixed layer depths (MLD; z_mld) for the stations (mat and csv files). Fluorescence measurements were done in connection with CTD (conductivity-temperature-depth) casts (SBE911+ system). MLD was defined as the depth where salinity increases by 0.01 between two pressure binned values (1 m bin size). The upper 15 m of the profiles was discarded due to spikes and possible disturbances by the ship and the profiles were filtered with a 7 pt running median filter to remove spikes.