Imagine taking a tube of ocean water from the rosette instrument in the photo, and wanting to find out the dissolved oxygen content in the water (which can tell you about living organisms, or biomass, in the water, or tell you more about where that water initially came from). How do you get it out of the tube, and into a controlled container in the lab, without contaminating it with the oxygen that you’re breathing? And how do you manage that when a team of other scientists also need to do their own experiments with the same samples? The answer is a combination of skill and teamwork, along with an eagle eye for details. Scientists monitor the rosette as it rises through the water, and when it resurfaces with bottles full of water samples taken at different depths, an assembly line begins.
One person is a logkeeper documenting the samples, 2 are runners who bring the samples into the lab, and 3 more prepare the samples according to how each team leader has specified. Then there are 2 more who prepare water samples for oxygen analysis. To get the water from the bottles with minimal contamination with oxygen from the air, they attach a tube to the bottle, and put the other end of the tube all the way down into a flask (see the flask and tube in the picture below). They let the water flow into the flask – and even overflow a bit, so that the water that remains in the flask is as uncontaminated as possible. (The flow also needs to be gentle, to minimize bubbles.) A stopper goes in the flask, and it’s ready for experiments! One of these scientists said to me that she was recently cleaning tubes and containers in the lab (usually not her favorite part of the job), and then she looked out the open door. There was the Arctic, which made it the best time she ever had cleaning glassware.
Hi Lindsay! I’m very suprised that you survive on a boat everyday. I could’nt do it. How do you setup this oxygen expirment? Were you nervous when you started your project?
Hi Dedric, I think you could live on this ship if you wanted to. It’s really busy, and a lot of work, but you have your bed, bathroom, and meals prepared for you, so it’s totally fine. But you would have to give up the internet and cell phone! (The internet is VERY slow and expensive to use here, and cell phones are just impossible.) As for the oxygen experiment, you have to prepare and clean the glassware, and set out numbered containers to put water in that you took from different depths. Of course you need the instrument (called the CTD, for conductivity, temperature, and depth) and a really long cable to send it deep into the water to take measurements! And you need a lot of chemistry knowledge and skill to work with the samples and extract the oxygen. The only thing I was nervous about when leaving for this expedition was being able to learn about everything onboard so I could share it with you and everyone on the blog (because there is a LOT to learn)!
Hi Lindsay,
I was wondering how you and your team decide where to gather your water from for testing?
Dear Marlene, great question! We have an expedition route planned out in advance be scientists. A lot of times, we travel along transects to take measurements. That means that we go along a straight line, and periodically stop to lower the instruments into the water for measurements. Usually these lines are chosen because they are where the ocean goes from very shallow (hundreds of meters) to very deep (thousands of meters). Different levels of water might be coming from different locations due to the complex currents of the Arctic, and each current might have slightly different chemical compositions, so we can find out a lot of information from those samples!
I found the oxygen experiment very interesting. I was wondering if you guys purified the water or just drank it how it is. If so, what process do you have to go through in order to purify it.
Hi Luiggi, the oxygen experiment was actually for scientific purposes, not for drinking. They study the oxygen content for a few reasons – it can tell them about the amount of life in a region, or if they make several measurements at multiple locations, it can also give them information about how water circulates through the Arctic. The drinking water onboard is from water bottles (we each get 1.5 liters daily). The tap water is desalinated seawater (meaning the salt is removed), and we were told not to drink that, and that the bottled water is safer.