Midnight Position N48º 51.5’ W029º 35.3’

We are now heading towards the northern sites. On the way we will be working a hydrographic section comprising 26 CTD stations. The first station on the section was back inboard at 0142. The section is just over 400 nautical miles long. The casts are roughly an hour and a half apart and the average water depth is 3500m. Terry, Darren, Paul, Jane, Andy, Ian and myself make up the CTD team. We are split into three shifts working four hours on and eight hours off. I’m fortunate, I’m working the 8>12 & 20>24, so I can have a normal nights sleep. The other two watches are more disruptive to normal sleeping patterns and it takes your body clock a while to readjust.
There was a torrential downpour around 5 o’clock just before the 2nd CTD of the day. The working pattern for the next 5 days has now been set, each watch will have a single CTD cast. The St Andrews team have also gone onto a watch system to monitor the EK60 during the transit between CTD stations. Monty, Jessica & Rhys are working on the CTD whilst it’s aboard to prepare a mounting for one of the Oceanlab cameras.
Victor and Gavin have taken extra water from the first CTD after breakfast and performed an optical cast at the same time.
Steve is working on the after deck preparing all the ropes and various other components which make up the two northern moorings. These will be full depth moorings with far more instrumentation than the two moorings deployed at the southern sites. Terry and I will be working on setting up the instruments in between the CTD casts over the next couple of days. In total we have 27 instruments to prepare for the two moorings, an assortment of current meters, temperature/salinity loggers, acoustic releases, sediment traps, beacons & lights.
Nikki & Ben are preparing one of the Oceanlab landers which will be deployed before the end of the section. This lander, as well as all four moorings, will be recovered during next summer’s ECOMAR trip aboard
RRS Discovery.
Mick is not having much success today with the binoculars, all in all a miserable day, no sun at all and visibility is very poor indeed.
Highlight of the day, dinner, even more so on a Saturday, it’s curry night. The ship operates a self service cafeteria system, great restraint must be shown, otherwise it’s down to the gym for payback time.
The late CTD watch passes without incident and then it’s time for bed.

CTD cast displayed in real time on one of the monitors in the main laboratory. Water bottles are closed during the upcast as required for subsequent nutrient, chlorophyll, oxygen & salinity analyses.

The CTD at the start of a cast. The package is lowered on an armoured cable with a central conducting core. The instrument is powered from the ship and the data is sent back to the ship in real time.

Colin Griffiths
Scottish Association for Marine Science, Oban.