Denman Marine Voyage returns after critical research voyage to glacier
After years of planning, and two months near the Shackleton Ice Shelf, the Denman Marine Voyage has returned to Hobart with enough data and samples on board to keep scientists busy for years to come.
Denman Marine Voyage
The DMV was RSV Nuyina’s first dedicated marine science voyage. It was also the first opportunity scientists working with the Australian Antarctic Program have had to study the waters around the Denman Glacier tongue.
The Denman Glacier is one of the largest but least-studied glaciers in East Antarctica and it is melting at a rapid rate. It holds enough ice to increase global sea levels by 1.5 metres if it melts completely.
“The Denman Marine Voyage seeks to fill a big hole in our understanding by collecting, for the first time, observations from the ocean next to one of the fastest retreating glaciers in East Antarctica,” Dr Laura Herraiz Borreguero, from CSIRO and the Australian Antarctic Program Partnership, said.
“We want to find out how vulnerable the Denman is to the warming ocean and the likelihood of it making a larger and faster contribution to sea level rise in the next few decades.”
The voyage was a collaborative effort involving 60 scientists from the Australian Centre for Excellence in Antarctic Science (ACEAS), the Australian Antarctic Program Partnership (AAPP), Securing Antarctica’s Environmental Future (SAEF) and the Australian Antarctic Division (AAD).
Science teams used many of RSV Nuyina’s 150 marine science systems to investigate the physical and chemical oceanography of the region, its biodiversity, geology and cloud forming processes.
Professor Jan Strugnell's SAEF team used the ship's beam trawl to investigate marine biodiversity around the Shackleton Ice Shelf.
“We're interested in understanding the connectivity and diversity of marine life, particularly the marine life that lives on the seafloor around Antarctica,” Professor Strugnell said.
“We're interested in understanding how different regions are connected, about source and sink populations, and the evolution of animals in this region. This information can be used to inform marine protected areas and conservation concerns."
A team from the AAD, led by Dr Leonie Suter, extracted environmental DNA from water samples, revealing the creatures living in the region without having to catch them.
“Every different depth has different communities and down at the seafloor you have the benthic habitat, which is completely different to the surface environment, so it’s really exciting to see those different habitats,” Dr Suter said.
For most of the voyage, scientists, support staff and crew worked across 24-hour shifts to make the most of the time away.
Professor Delphine Lannuzel, from the University of Tasmania and ACEAS, said the enthusiasm of the early career researchers – which made up nearly half the science cohort - kept everyone’s spirits up.
“They’re really receptive to learning,” she said.
“They learn from the senior people as well. There’s that transfer of knowledge from more senior researchers to younger researchers, which is really beautiful to see.”
Professor Delphine Lannuzel (left), from UTAS and ACEAS, and colleague with trace metal instruments
“They’re going to improve our models and develop our understanding of climate change”
It was the first time working at sea for many in the science teams. It was also the first time many of the ship’s marine science systems were deployed in the setting they were designed for.
“We knew Nuyina was an exceptionally capable vessel but to be able to put it to the test on this voyage and see it achieve and perform as well as it has, has been really gratifying,” Dr Stringer said.
Scientists will now take their samples back to the lab, where they’ll be analysed and written about for years to come.
Findings from the Denman Marine Voyage will complement those from the earlier Denman Terrestrial Campaign, which based scientists near the glacier’s inland reaches for two summers.
Dr Stringer said: “Together, they’re going to improve our models and develop our understanding of climate change and the affect it’s going to have on biodiversity in our region.”
For many on board, the science work was just one part of the experience.
“I think my favourite part of the voyage was seeing the community coming together,” Professor Lannuzel said.
“It didn’t matter which discipline or program you came from, everyone was united under one banner, and I think for me that was the highlight of the voyage.”
A range of intriguing marine creatures, including this clio pyramidata - a type of sea snail - were captured using the ship's wet wellPhoto: Pete Harmsen
