During Leg 2 of the Oceanography and Climate Change Survey, the aim is to conduct further CTD operations across two transect lines off the west coast of Ireland, approx. every 18 nautical miles. CTD stands for Conductivity, Temperature and Depth. The CTD collects water samples at different depths using niskin bottles which are triggered using the Seabird software system located in the dry lab; this is what I have been doing, along with other scientists during their shifts. Conall O’Malley, one of the students from the SMART sea programme, provides a thorough description of the function of the CTD in his blog at http://smartseaschool.blogspot.ie/.
Once the water samples have been collected, the water from the niskin bottles will be used to gather information on dissolved oxygen (DO), dissolved inorganic carbons (DICs), salinity and nutrient concentration, including phosphates, silicates and nitrates. Box core samples will be taken at different locations along the transect line during the second leg of the survey also.
CTD deployment.
On 12th January, I was given my set shifts for the remainder of the survey – I would be working 8 to 12, morning and evening, every day. The vast majority of the day was spent on passage to the location of the first CTD station, just off Inis Oirr island, and we arrived at 21:30. Last night though Xavier and the crew were busy taking grab samples! On January13th, CTD operations continued along the first transect line – the good weather meant we made good progress with nine stations completed today.
14th January
The good weather on January 14th meant the M6 weather buoy could be deployed – the entire process took just over 2 hours as the mooring is over 5000 metres in length. This 5000 metres of rope has to be released from the net drums located on the aft deck. The next task was to head to the location of the old M6 weather buoy in order to recover it and bring it back to the engineers in Galway for maintenance purposes. Tomasz Szumski has given me some great photos of the entire process from deploying the new M6 weather buoy to recovering the old one!
Figure 2: The crew recovering the M6 weather buoy!
Figure 3: Davy Murphy on the aft deck with the other crew members.
Nine CTD stations were completed today – they are taking a bit longer at just over 2 hours for one CTD as we head into depths of over 2,400 metres.
In other exciting news we saw pilot whales! Check out the photos below! And also thanks to Kenny Downing, the chief officer for this survey, I am learning the basics of navigation (or more like navigation for dummies!) for an hour in the evenings. Thanks Kenny! So all in all having a great time here on the Celtic Explorer…
Figures 5 & 6: Pilot whales seen along the Porcupine Bank.



thanks for share...
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