Southern Ocean GasEx Blog

Dispatches from the Southern Ocean Gas Exchange Experiment


Posted by sogasex on March 28, 2008

By David Ho, LDEO

Being out at sea requires that we adapt to different situations and adjust our plans accordingly. Some of these adjustments are expected, while others are genuine surprises.

For instance, when we inject the tracer patch, we select an area that is relatively stable so we don’t end up chasing the tracer patch around the Southern Ocean. However, because there’s no guarantee that winds and currents won’t change, we really don’t know where the patch is going to go. As a result, we don’t have fixed survey lines and have to adjust them minute by minute. That’s expected.

During this cruise, we’ve had some surprises. For instance, what happened to the SuperSoar was a surprise (see Burke’s blog), but given the fact that they are pushing the cutting edge of water sampling technology, it’s not difficult to accept that it could happen.

What happened to us today topped that.

It was about 9:00 am, and time for our morning CTD. Paul and I were discussing something in the Hydro Lab and getting ready for sampling when we heard a loud thud. I said to him facetiously, “I hope that wasn’t the CTD going into the screws [the propellers].” I went to the Staging Bay to check things out, and ran into Carlos on the way who said to me with a panicked voice, “we just lost the CTD.”

I once heard an episode of WNYC’s Radio Lab about Stress, where they talked about what happens to us when we’re under stress. One of the common experiences that people under extreme stress has is that time slows down and thoughts become clear and lucid.

In the few steps that it took to get to the Staging Bay, all the different scenarios under which we could have “lost the CTD” crossed my mind. I was expecting to see the end of a frayed cable dangling in front of me; what I saw was more surprising.

The CTD was hanging off the side of the ship, and the block that used to hang from the CTD boom was laying on the deck. See pictures below for what I fail to convey with words. Apparently, the rosette was accidentally pulled into the block, breaking the block and sending the CTD crashing approximately 20 feet into the side of the ship. Disaster!

The good news out of all this is that nobody was hurt and the rosette/CTD package was eventually recovered. However, the rosette frame was severely damaged and eight sample bottles were crushed.

For the 9:00 am station, we adapted and went to our storm contingency plan, when we expected not to be able to deploy the CTD: Submersible pump. Even though the pump only had enough hose and cable to sample down to about 40 m, it was better than nothing. It was a nice sunny day and a communal atmosphere on deck as we took turns sampling water pumped up to the surface.

We’re working hard to put another rosette/CTD package together, but it will not be ready in time for the upcoming 9:00 pm station. This will be another pumped sampling station. We hope to have the CTD ready for the morning station tomorrow.


Damaged rosette/CTD hanging off the side of the ship


The broken block on deck


Recovering the damaged rosette/CTD


Close-up of the damage


Preparing the submersible pump


Sampling from the submersible pump


A new rosette/CTD being assembled in the Staging Bay

UPDATE: Sara, Geoff, Jonathan, Clay, and Bob worked hard all day and assembled a new rosette/CTD in time for the 9 am morning cast the next day. We’re back in business. Nice going!


The newly assembled rosette/CTD package, ready for the next cast


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: