Antarctic expedition may aid search for life beyond Earth

What does Antarctica have to do with one of Jupiter's moons?

Much more than we might think – what Kiwi scientists discover on Earth's windiest, coldest and driest continent may even aid the search for signs of life on Europa, 628.3 million kilometres away.

But, more pressingly, their study into Antarctica's sea ice formation could answer important questions about how climate change might affect us.

"By looking at what happens where the sea ice meets the ocean, scientists will be able to use this information and apply different climate scenarios to 'see' into our planet's future," said Niwa marine physicist Dr Natalie Robinson, who is presently leading a team on the ice.

Each year, the sea ice around Antarctica expands in winter and retreats in summer, doubling the size of the continent.

This marks the largest annual physical change on Earth and influences the atmosphere and the ocean.

Robinson's work looked at how cooler water flowing from under the Ross Ice Shelf met a warmer ocean and contributed to sea ice growth - and how melting the ice shelf from the ocean below contributed to loss of the ice shelf.

Antarctica New Zealand acting chief scientific advisor Dr Fiona Shanhun said this work posed some globally significant questions about sea ice.

"The long-term trend shows Antarctic sea ice extent has been increasing, despite a warming ocean," she said.

"This goes against climate-model predictions. Dr Robinson's work seeks to understand how and why more sea ice is forming, and this understanding will contribute to improving climate models."

This year, Robinson's team would collaborate with US scientists who were collecting data underneath the sea ice with a purpose-built underwater robot funded by Nasa.

Robinson's team, working from the surface, would measure the thickness of the sea ice.

The two teams would then be able to share and compare information which may have implications for exploring life on Europa.

Europa is one of Jupiter's 79 identifiable moons, with an ocean that lies below a thick ice shell.

Like Earth, it is thought to have an iron core, a rocky mantle, an ocean of salty water - and perhaps even environments where life could exist.

"Antarctica is the closest Earth-based comparison to Europa," Robinson said.

"We can test instruments here for potential use on Europa. Looking at what happens beneath the ice and its effect on our planet may give us prior understanding of what could be discovered on Europa."