Tuesday, April 30, 2013

CTD Palooza

Me freezing in Flandres Bay.
For the past two days we have been working almost non-stop, but we have gotten a lot of good data from it! There are several different groups of scientists on board the ship, and I am part of the "biology" group (even though I'm a chemist); there are also geologists (they study rocks and sediments), glaciologists (studying the movement and melting of glaciers), and physical oceanographers (studying the currents and the movement of water masses in the ocean). All of us have different research goals, and depending on the location of the ship and weather conditions, different groups have been working at different times. The past two days was our turn to work a lot, because the weather was too bad for the helicopters to fly (for the glaciologists), and we were not in a good location to collect sediment cores (for the geologists) because there was hardly any sediment on the ocean bottom.

The CTD entering the water in Flandres Bay.
When we are working, we mostly use the CTD rosette in order to collect water. It has 24 bottles on it, and each bottle can be closed at a different depth in the water in order to collect water from that depth. We watch the instrument as it moves down in the water on a computer screen that shows us what all of the sensors are reading (like temperature, salinity, etc...) and from that we can decide where we want to collect samples. Then, we press a button on the computer in order to close the bottle when we are bringing the instrument back up to the ship at certain depths. Each time we put this instrument in the water it takes about 1 hour for it to go down to the bottom and back up again (about 300 meters, or 600 feet down), and then we collect the water and filter it or process it in various ways depending on what we are measuring. The filtering can take anywhere from 1-4 hours, so it is a lot of work! We did 20 CTD casts in two days, so we were all very exhausted afterwards. Most of us slept for only 3 hours during that time, so we took long naps today in order to catch up. We did the sampling in a very beautiful bay called Flandres Bay, so it was worth it. There are several glaciers feeding into this bay and we were interested in seeing if the melting of these glaciers was effecting the circulation (currents in the bay) and the biology (the growth of phytoplank
ton, and the growth of animals that live on the seafloor).

Crabeater seals in Flandres Bay.
Now we are mostly done with the biological work, and the geologists and glaciologists will be trying to finish their work for the rest of the cruise. We are now trying to go to different locations so the glaciologists can fly the helicopters to the land in order to install some instruments, but the weather is bad in a lot of places so it is difficult for them to get their work done. They are all kind of sad about that, so we are thinking sunny thoughts so they can hopefully fly!

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