Is Antarctica melting?

Dr Nancy Bertler from Te Puna Pātiotio—Antarctic Research Centre answers:

"Yeah, over the last few years we actually saw the surface of Antarctica melting. But the real problem is that the Antarctic ice is moving ever faster into the ocean, and that raises the sea level.

"So there’s two ways ice sheets can contribute to sea level rise. One is by the ice sheets just melting from the top, and you see that water running into the ocean. And the other one is where the ice moves ever faster from the centre of the ice sheets to the edges and drops off into the ocean. While Greenland is mainly driven from melting from the top, Antarctica is mainly driven from that ever faster moving ice into the ocean.

"So over the past 10,000 years sea level has been incredibly stable. But for the past century, as global warming kicked in, we saw sea level rise by over 20cm. Since 2006 we now see that the shrinking of polar ice sheets and the melting of glaciers is the main driver of sea level increase.

"We have to halve our emissions by 2030, or else we will initiate the irreversible collapse of the West Antarctic ice sheet. Once initiated, this cannot be stopped. Our actions right now will impact generations to come.

"This problem is urgent, the consequences of sea-level rise will affect every aspect of our society. We need the talent of all kinds of people to come and work together on this really complex issue. And together, we might be able to save the Antarctic ice sheets."

Related links

• Ask a researcher
• Outreach programme
• Study science