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31.08.2016 06:20 Age: 1 year
Category: Home Slider, SOOP

IMOS communicators head to sea on the RV Investigator

The IMOS Communication Managers Marian Wiltshire and Warrick Glynn have just returned from a 5-day Transit voyage on board the Marine National Facility RV Investigator.


View of the Foremast with a backdrop of the entrance into the Sydney Harbour. Image: Marian Wiltshire. MNF

Marian and Warrick under the A-frame on the back deck. Image: Warrick Glynn. MNF.

IMOS OceanCurrent now shows the location of the Investigator. In this plot you can see the ship track north into an eddy of the EAC.

Stephen Thomas of the MNF with the IMOS In Situ SST Autonomous Radiometer that measures sea surface temperature. Image: Warrick Glynn. MNF.

Whilst the main objective of the voyage was to move the RV Investigator from Hobart to Sydney ahead of it's next science voyage, some science did take place whilst we were at sea. Associate Professor Andrew Bowie, a Chemical Oceanographer with the Antarctic Climate & Ecosystems CRC ran a supplementary project examining the natural iron fertilisation of the oceans around Australia. The project will facilitate an integrated ship-based atmospheric observational program for trace elements in oceans around Australia. Andrew and his students collected aerosol samples in the ship's aerosol laboratory (located in the bow of the ship), tested a new dual chimney precipitation sampler, and collected underway water samples. The water samples will enable the correlation of the atmospheric flux of trace elements with the surface in-water concentrations.

Two members of the Australian Seabird Group were also on board to conduct a bird survey. Nicholas Carlile and Mick Roderick spent all of their time (during daylight hours) up high in the monkey bridge observatory on level 7 of the vessel. Both were impressed with this specifically designed observatory and noted that their at-sea bird observations were collected along-side oceanographic data which will improve their understanding of seabirds and the way they relate to changing ocean environments.

IMOS collects a number of continuous observations with the RV Investigator including underway CO2 measurements, sea surface temperature, real-time air-sea fluxes, bio-acoustic data and deploys a Continuous Plankton Recorder to collect plankton samples. Warrick and I were able to locate, with the assistance of Stephen Thomas of the MNF, all of the equipment that take observations for IMOS, and look at the bioacoustic data in the operations room with Amy Nau.

We also assisted in the deployment of an expendable bathythermograph (XBT) and the Continuous Plankton Recorder (CPR). This gave us an introduction to the on board protocols for the deployment of even small pieces of equipment, and how important the interaction between the ship's crew, the MNF support staff and the scientists is to ensure a successful and safe deployment. The RV Investigator also deploys our deep water moorings at the Southern Ocean Time Series site and the East Australian Current (EAC) array off the coast of Brisbane, and our experience on this voyage gives us a new appreciation for the complexity and difficulty of these deployments.

We were lucky enough to take an extended tour below main deck with the Chief Engineer, including the engine room, winch room, the container room, steering gear room, and the drop keel room.

The voyage also collected additional swath data for the Australian Hydrographic Office. Even though 70% of Australia’s territory is underwater, only 25% of Australia’s Exclusive Economic Zone has been mapped with multibeam.  The Investigator can map the seafloor in 3D and can do it faster and with greater resolution than the previous vessel, Southern Surveyor. The Chief Mate in one of discussions on the bridge said that the vessel takes a slightly different route every time to ensure we map a new section of the seafloor.

Our short voyage aboard Australia’s only blue-water research vessel was fascinating, from watching how the scientists and crew work, to understanding how the IMOS observations are collected and where the equipment is located.

We would like to thank the Ship’s crew, MNF staff (in particular Tegan Sime, Ron Plaschke and Matt Marrison) and our fellow participants for an amazing trip.

Whilst the voyage schedule has been set for 2016/2017, 2017/2018 and applications have closed for 2018/2019, there is the opportunity to apply for ship time for piggyback projects. A Piggyback project needs the support of the Chief Scientist to be integrated into the existing science program before it can be considered by the MNF. For more information visit the MNF Piggyback project page.