by Nikki Clargo
Day 13. Wind force 6. Sea state: moderate. Weather: grey, with a distinct lack of sun (particularly during “summer”). Visibility: poor (although this could be due to considerable salt-spray on the windows of the conference room). CO2 team morale: high, because this is our first break since sampling started, and we’re looking forward to pizza for lunch.
Well, now the scene is set, I’ll introduce us. I’m Nikki Clargo, and myself and Dr Lesley Salt comprise the CO2 analysis team aboard DY031, helped by Caroline Mengeot, Caroline Kivimae and Katerina Giamalaki. Although Lesley and I are both British, we represent the “foreign contingent” on this cruise, as I work at the Royal Netherlands Institute for Sea Research, and Lesley is based at the Station Biologique de Roscoff in France. We are fortunate enough to have been asked to join this cruise as carbon analysts, and as this is our sixth cruise measuring carbon together, we know the routine pretty well! We’re even set to beat our record for number of samples measured; our current total is 450 and we still have a week to go.
To achieve this we simultaneously run two VINDTAs (Versatile Instruments for the Determination of Titration Alkalinity). These instruments are capable of measuring both dissolved inorganic carbon and total alkalinity, which can then be used to calculate other parameters such as the pH and partial pressure of CO2 of seawater. The collection of carbon data over multiple years, such as on the Extended Ellett Line, enables us to monitor the phenomenon known as “ocean acidification”. This occurs due to the absorption of CO2 by the ocean from the atmosphere. As a result of increasing atmospheric concentrations of CO2 due to human activity, more and more CO2 is entering the oceans, and because of the way in which it reacts with seawater, this causes an increase in acidity. This may be problematic for corals and organisms that use carbonate in their shells, as they may start to dissolve in more acidic conditions.
Life at sea as a carbon analyst is fairly intense. As our instruments run 24 hours a day, we work rolling 8 hour shifts, from 12pm-8pm, 8pm–4am and 4am-12pm. This means that we alternate between “long” and “short” days, which does take some getting used to, but we find this is the best shift pattern for this kind of work. This is made far more pleasant by the comfort of the RRS Discovery, and as it is our second cruise aboard, it was great to be greeted by familiar faces amongst the crew upon arrival. When we do get a bit of spare time, we watch films (the ship has an impressive DVD library), go to the gym, play darts, and sleep at every available opportunity. We’re well fueled by the amazing efforts of Lloyd and Jackie, who produce excellent British food that we both miss at home. Our personal favourites include fish and chip Friday, a never-ending stockpile of chocolate digestive biscuits and of course, the much anticipated Sunday roast. These in addition to Penny’s endless supply of chocolate, which she has the unique skill of producing when you seem to need it most (best chief scientist ever), keep spirits high and enable us to keep measuring all that carbon!
Photos by Nikki Clargo
The CO2 team (Nikki Clargo, Lesley Salt) eagerly awaiting departure from NOC
One of the two VINDTAs that we use to measure the carbon system