Tuesday, 11 August 2009

Day 3 – 9th August

After my late shift yesterday I slept in till around 10 ish. Since terminating the CTD transect the boat had begun moving into the Alexander Fjord on Ellesmere Island (the western boundary of the Nares Strait) where we planned to recover and deploy a pressure mooring and also recover a cache of equipment for Michelle who is an ice scientist with the Canadian National Research Council. There were no CTD sections to be done so we used the time troubleshooting the issues from last night. After a good proportion of the ‘day’ gone we finally concluded that the issues were being caused by the water pressure forcing water into the sea connectors over time and therefore shorting out the data cable. We attempted to solve this issue by creating a grease sleeve around the connector with rubber glove fingers. Our early test suggested this worked and therefore after the work in the Fjord was complete we headed back to the Smith Sound CTD Section
The route too and from the Fjord took us through some of the heaviest ice we have encountered so far. This is likely to be a recurring pattern throughout the cruise as the ice that is flowing south at 1ms-1 from the Lincoln Sea will get piled up against the eastern boundary due to the Coriolis effect (an effect resulting from the rotating earth which causes moving objects in the Northern Hemisphere to be deflected to the right). This ice could cause significant problems throughout the cruise as majority of it is multi year ice (ice that has not melted over summer) and therefore can be significantly thicker than what the boat is able to break through. This means that it can prevent us from firstly completing CTD sections without using the helicopter to carry the CTD off the boat for on ice deployment and secondly can prevent moorings from being recovered if they pop up under the ice. The only solution is a lot of patient waiting for a window in the ice which we can move into, complete the work and get out again before we get trapped in!
We arrived at the start of the CTD section at around 11pm after having to skip the location of the first profile due to heavy ice. I had managed to get a couple of hours sleep after dinner and therefore was asked to complete the section with Helen a scientist from Oxford University. She was operating the computer and I was on the winch. We had to complete another 9 profiles to complete the section which is about 4 hours work. It was a beautiful evening/night with clear skies, no wind and a temperature of between 0 and 1oC. Of course we had the sun to keep us company all night but even so it gives out absolutely no heat – it is simply a light source! The first 5 profiles went without a hitch but on the 6th it all went to pot! It was 2.30am in the morning by now and both Helen and I were beginning to flag. We woke up Berit and Adreas (both from the University of Delaware) to help troubleshoot the issue and then take over to complete the last couple of profiles. We decided to replace the grease sleeve on the sea connector in the hope that it had failed instead of the issue being a new problem. By 4.00am we were ready to try again, but by this point Helen and I were so tired we left Berit and Andreas to it and headed to bed at last!!

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