Australia's Antarctic season has wrapped up with the return of icebreaker RSV Nuyina from Macquarie Island today.
Over two weeks, scientists on board performed end-of-season research before winter takes hold, with native cushion plants, elephant seals and climate monitoring work in their sights.
The ship also delivered 484 tonnes of cargo, including tractors, excavators and food, to keep the station going for another year.
The season began as it ended, on Macquarie Island, with an expeditioner changeover seven months earlier, using chartered icebreaker MPOV Aiviq.
Aiviq then headed further south, with a new crew and supplies for Davis research station. Happy Diamond joined the fleet to help resupply other stations in later voyages.
The two big scientific and operational highlights for the year, however, were the establishment of a field camp near the Denman Glacier, and a 2300 kilometre-return tractor traverse to a million year ice core drilling site at Little Dome C.
Australian Antarctic Division Chief Scientist, Professor Nicole Webster, said the Denman Glacier camp, 450 km west of Casey, will accommodate 40 scientists and support personnel undertaking climate research.
"We already know the Denman Glacier is vulnerable to climate change and holds a potential sea level rise of 1.5 metres," Professor Webster said.
"Field work and research will address the risk of ice mass loss on time-scales from the next few decades to centuries."
At Casey, Traverse Leader Sharon Labudda and her team, spent 52 days travelling to and from Little Dome C, high on the Antarctic plateau, to deliver scientific equipment and supplies for an ice core drilling camp that will begin work later this year.
Lead ice core project scientist, Dr Joel Pedro, said the multi-year quest to drill an ice core with a climate history dating back one million years will provide new information to test climate models and resolve long-standing questions about the timing of ice ages.
"In particular, it will help answer why there was a major change in the ice ages cycles around a million years ago, with a shift from smaller ice sheets and regular 41,000-year cycles to larger ice sheets with ice ages every 100,000 years," Dr Pedro said.
This year, Ms Labudda navigated a new route for the five tractor trains, to deliver equipment and supplies to the site.
Her team also collected shallow ice cores near the future drill site, to give scientists an initial look at the snow chemistry and climate data they contain.
"Our mission really was just to get there and hopefully get to take some ice core, which we did," Ms Labudda said.
"I think having the traverse capability will open up a larger, different range of science that we can do in Antarctica."
The return of RSV Nuyina to service and its successful mission to Macquarie Island suggests next season will be just as busy and exciting.
