Mooring works (2/2)

Recovering the 2 years old mooring is of course just one part of servicing the mooring. After getting back all the instruments, we need to conduct a calibration with each instrument. Therefor they get attached to a CTD to check whether they are still measuring accurately or show some drift. This calibration cast are mostly done during the nights as there is not daylight needed. It just takes some time as we do a few stops when getting the CTD rosette back up.

Working during the day, most of us are happy to get as much sleep during the night as possible, but when there are calibrations cast there is no guarantee for that. For some works you just leave some notes for the night watch what to do. But for some works the night watch needs to wake you up. The sound of the ringing phone during the night is maybe the most disliked sound here in on board. For those being on watch during night it is quite nice to have some more company during the sometimes-lengthy calibrations cast.

A package of floating elements is prepared for the deployment in front of two anchor weights.
Photo: Patricia Handmann

When all instruments are working well, they can be deployed again. In the lab the instruments will be programmed and sorted to have the right kinds ready for each mooring. The deployment itself is a routine by now. Wire is given out from a winch and instrument after instrument is attached to it, with a couple of floating elements in between. Everything that is protocolled for the ones who going to recover it in about 2 years. Always starting with the top element of the mooring the ship, which is slowly moving towards the correct position, carries a up to 3-kilometre-long tail of floating elements. When reached the right position it’s time for the anchor drop. The anchor consisting of a couple of hundred kilograms of old train wheels is dropped in the water and the floating elements are diving down on after the other. Now our works is done, and we can only hope that all instruments will work well for the next to years.

Attaching floating elements to the mooring.
Photo: Christiane Lösel

As we had some bad luck with some fog for the first recovery, we were rewarded with a group of whales showing up right before we were done with our first deployment.

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