A huge milestone has been reached: our first DYNAMO buoy has been deployed in the Beagle Channel in the middle of September and will be sending data for several months from now on. Thanks to our colleagues at the CADIC institute the buoy reached Ushuaia Bay and sends environmental data including air temperature, wind speed, wave height, water temperature and conductivity on an hourly basis. Located in close proximity to the CADIC it is now possible to establish routines and gain experience concerning the calibration of sensors as well as the maintenance of the buoy itself. We talked to Jacobo Martín, the responsible colleague on site, and asked him about his experience while deploying the buoy.
Jacobo, the buoy is in the water. Congratulations to you and your team. What was more difficult? Putting the mooring in the water or deploying the buoy?
Due to the heavy weight, putting the mooring in the water was more difficult. Luckily, we had the support of R/V ARA Puerto Deseado to fulfill that task. Afterwards, it was relatively easy to tow the buoy with our Zodiac and attach it to the line previously deployed. However, it was easy but ice-cold too. I was wearing a neoprene suit, which was wet after assisting in dunking the buoy in the water from the dock. I thought it was not worth to change clothes because the site is fairly close to the dock. But then I realized that the Zodiac had to navigate very slowly to ensure the stability of the towed buoy. It seemed to last forever to reach the place at a given speed of 1-2 knots.
What kind of weight and cable did you use for the mooring?
The weight is a train wheel. A set of 5 train wheels were recently donated to CADIC by Dr. Alberto Piola (SHN/UBA). Discarded train wheels are a first choice for oceanographers worldwide as ballast for moored lines. For the present case the ballast was maybe a bit oversized (320 kg), since this buoy in particular is a small, light model. But that was the ballast we had at hand (on deck in fact) at the moment when there was the opportunity to do the work. The rest of the mooring consists of a galvanized chain, galvanized shackles and swivels, and a Dyneema rope with a diameter of 10 mm. At the moment the mooring is located roughly at a water depth of 30 meters.
Did everything go to plan or did you have problems with something?
There are always surprises that force you to improvise. But both operations, mooring and buoy, went without major problems. More importantly, we had fair weather conditions, which is the most crucial factor down here in the South. And it should not be forgotten, that the administrative paperwork to make all this possible is hard work too and takes a lot of time.
How many people were involved in deploying the mooring and the buoy?
The weight and line were deployed with the help of the full deck crew of the R/V ARA Puerto Deseado. For the buoy, we were four people, including the pilot of the Zodiac. This was necessary to lean and attach it to the trolley, bring it to the dock, put it in the water, tow the buoy in position and finally attach it to the line.
Who will now maintain the buoy and how often?
We are setting up a “DYNAMO buoy team”. Several researchers and technicians at CADIC have volunteered already to ensure the buoy is safe and serviced. The idea is that there must always be someone in place if others are out for other missions, get sick or are on holidays. We have set a schedule of one maintenance visit at least every month to check the buoy for functionality, corrosion or any other issue. Cleaning bio-fouling from the sensors and surfaces will be another important task we will perform during the monthly checks.