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Drygalsky Ice Tongue and sea ice. Photo: Liv Cornellisen

Drygalsky Ice Tongue and sea ice. Photo: Liv Cornellisen

Podcast: The sea ice factories of Antarctica

21 March 2024

If you want to study the health of the world's oceans, you need to get to their heartbeat.

That's deep in the Ross Sea, where the sea ice factories of Antarctica - or polynyas - live.

Because of their remote location and harsh weather conditions they're tricky to measure, and they're under-represented in our climate models.

But a crew of Antarctic Science Platform scientists have just returned from observing them, sending their state-of-the-art ocean gliders out to collect information.

They hitched a ride on the Italian icebreaker Laura Bassi, which was ironically able to get closer than usual because of melting sea ice.

The journey was a reaction to the collapse of sea ice last year, and had to be organised in a hurry.

"Science can move slowly most of the time," says Craig Stevens, the voyage leader on board the boat.

"It takes you a few years to decide on a problem, to write a proposal, a few years to do the work and a few years to publish it.

"We just don't have that time any more in terms of identifying the changes, and communicating the seriousness of that to all audiences, stretching from school kids to policy designers and everyone in between."
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Preparing moorings Photo: Liv Cornellisen

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Deploying mooring Photo: Lana Young

Radio New Zealand's The Detail spoke to Stevens, NIWA's principal scientist, and to Liv Cornellisen, two of the 12 New Zealand scientists who were on board the Laura Bassi.

- Listen to the podcast: The sea ice factories of Antarctica

- Learn more about the Ross Sea Voyage 2024

Voyage Science

The New Zealand science plan had three key objectives.

Ross Sea Polynya

Polynya are sea ice production factories. They are (i) difficult places to make measurements and (ii) poorly represented in climate models – and knowledge of them is critical at a time of rapidly declining sea ice. Our goal for the voyage is to deploy state of the art sensors designed to operate and gather information over a range of spatial and temporal scales, to develop new knowledge of Antarctica’s most productive polynya – the Ross Sea Polynya.

Ross Sea region Marine Protected Area (MPA)

We will use a range of current research tools, including isotopic analysis, gene-scaping, eDNA, acoustics, gathering of key environmental measurements, and deployment of ROVs and ocean gliders, to study Ross Sea pelagic and benthic (coastal) ecosystems. This data will be used, along with existing and future research, to establish a baseline of the Ross Sea region MPA ecosystem function and coastal biodiversity to determine how vulnerable this ecosystem is to the future changes anticipated for this region.

Seabed coring

An important aspect of Platform research is to use sediment records to better understand how the Ross Sea responded to historic climatic conditions. Knowing how sea ice was distributed, and how that impacted on primary production at times when the climate was naturally warmer can inform predictions of how things will respond when such conditions return. To support this research, we aim to collect and analyse shallow cores along the front of the Ross Ice Shelf, areas that we have seldom visited, to enhance existing transfer functions.