Scientists returning from a voyage into Antarctic waters say they found worrying evidence about how much ice has melted and how quickly.
The ice-breaking ship the RV (Research Vessel) Laura Bassi returned to New Zealand waters on Saturday morning after two months in Antarctica's Ross Sea, which is part of the Southern Ocean.
The team of New Zealand scientists from the Antarctic Science Platform - along with a research team from the Italian Programma Nazionale di Ricerche in Antartide - crossed the Ross Sea on the ice-breaker to witness the sea ice retreat first-hand.
A team of New Zealand and Italian scientists have braved freezing temperatures and high seas to gather more data, which shows worrying clues about the melting Antarctic ice. Photo: Supplied/ Lana Young
Their research found that the ocean - the southernmost on the planet - is changing substantially, said NIWA and University of Auckland professor of physical oceanography Craig Stevens, who led the New Zealand team.
Dr Craig Stevens on board the RV Laura Bassi Photo: Supplied/ Lana Young
They found the area covered by ice had decreased dramatically, and in the past couple of years there had been record lows of the amount of ice surrounding Antarctica
While the amount of salty and oxygenated water getting into the deeper parts of the oceans was changing.
Ross Sea ice photographed during the expedition Photo: Supplied/ Lana Young
The changes to the sea-ice indicate that in the coming decades coastal cities will need to be reconfigured because of sea level rise, Stevens said.
While the effects these changes will cause to ecosystems will impact mammals like penguins, whales and seals, and weather systems would also change around the Southern Ocean.
The team of New Zealand and Italian scientists Photo: Supplied/ Lana Young
With a climate emergency underway, the work they were doing was urgent, he said.
"The scientific community [has] really got its pedal to the metal on this because it's such a major challenge for humanity.
"This is going to affect ice shelves. It's going to affect marine ecology. It's going to affect sea level rise."
Sunset over the Ross Sea Photo: Supplied/ Lana Young
Stevens said the research trip had allowed them to deploy robots, leave behind instrumentation to collect data and take measurements of all sorts of marine DNA and zooplankton.
But he said further research was needed to collect more data to inform their forecasting models better.
He hoped the information would be used to inform future government documents, such as for regional planning, and to inform the public about how the planet is changing.
The expedition route Photo: Supplied/ Starboard Maritime Intelligence