Cruise Report, RV ATAIR, Cruise 0671021-1, Bremerhaven - Thyboron - Aberdeen, 18 Jul —- 10 Aug 2023 | 
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The CTD system worked well during the whole cruise, and all sensors showed reliable meas- 
urements. The differences between redundant sensors were small and mostly within uncer- 
tainty range as given by the manufacturer and later calibration. Larger differences were ob- 
served under rough measurement circumstances or due to large numbers of particles within 
the water column clogging the sensor packs for short times. One cast had to be stopped and 
redone due to computer failures (black screen), the CTD system itself was always reliable, 
NMEA-formatted GPS data were always available and added to the casts. 
X TION 
S-1D181015 
S-1D181004 
S-1D181005 
S-1D181014 
S-1D181011 
S-1D181010 
S-ID181003 
Manufacturer 
General Öceanics 
u“ 
“ 
u“ 
'n 
| CALN 
bottom 
bottom 
10m 
7.5m 
5m 
5m 
25m 
Table 5.2. Overview on the Niskin bottle set-up and sampling scheme of cruise 0671021-1 
All Niskin bottles were checked at the beginning of the cruise and then closed during the upcast 
at the designated sampling levels. Before closing, a 3 min waiting time was applied to avoid 
antrained water from different depth levels being taken as a sample. Salinity and oxygen 
samples were always taken from Niskin bottles located on positions 2 and 6, see Table 5.2. 
On station #090/GN053A, bottles were closed after 30 sec to 1 min waiting time due to strong 
zurrents and the risk for the CTD to be pushed underneath the vessel. On station #100/GN050. 
the surface salinity sample could not be taken due to cancellation of station work caused by 
axtremely bad weather conditions. 
5.3 
Water Sampling with respect to Salinitv 
Water samples were collected at all stations during cruise 067/021-1 for the purpose of 
checking the quality of the CTD-derived conductivity and, consequently, salinity. An exception 
was made at the test station at the start of the cruise. Water samples were taken from Niskin 
bottles closed at 5 dbar near the surface and at the bottom. The bottles were numbered and 
finsed three times with seawater before being filled and sealed airtight. The water samples 
were analysed using an OSIL AUTOSAL 8400B salinometer, s/n 68046. Analysis of