Recovering an oceanographic mooring

So in my previous post we deployed a mooring (in fact, those pictures were from the deployment of several different moorings). Now how do we get such a monster back on board again?

Recovering a mooring is always slightly nerve-wracking, because even though we’ve tried very hard to forget about this possibility during the year the mooring was out there in the ocean, it is never 100% certain that we will actually be able to recover it. It might not be there any more, or it might be out of batteries. I have been on cruises where we have had to give up on recovering moorings, or on another one where we had to dredge for a mooring (and found it!). Luckily, on this cruise things went smoothly and the way they were supposed to:

A sound signal is sent and establishes contact with a releaser that connects the anchor with the rest of the mooring. After establishing the position of the mooring, a signal is sent and the releaser lets go of the anchor: The mooring floats up to the surface!

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Then, the task is to spot the orange floatation thingies in the waves.

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And bring the ship close enough to actually connect a hook to it.

 

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Once it is on the hook, it needs to be brought on board.

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Remember, it’s hundreds to thousands meter of rope we are talking about! Luckily the Håkon Mosby is (as all research ships are) equipped with plenty of winches and cranes and a super helpful, knowledgeable and skilled crew.

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Instruments are brought on board individually (or, in this case, a releaser).

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After having been out in the ocean for a year or two, they are sometimes overgrown with stuff. And in this particular case, that bio stuff was stinky!

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But pretty, I have to admit. I think it’s some sort of cold water coral. I think. Any biologists here?

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But there is always a lot of stuff to be recovered.

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And also pretty interesting: This is the first time I got a good look into one of those orange flotation thingies. I knew there was a glass sphere inside, but it was nice to actually see one. I had previously seen one that had imploded – it ended up pretty much pulverized. But so this is what we knock around on deck and throw out into the ocean:

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But yeah. In a nutshell, this is how moorings are recovered.