Dramatic loss in Antarctica sea ice concerns NASA

NASA scientists are concerned about a dramatic fall in the extent of sea ice around Antarctica.

The frozen area circling the continent has plunged from a record high to a record low in just three years.

Scientists studying Antarctica have long puzzled over why the icy continent hasn't seen the same trend of sea ice loss as the Arctic has.

"We've seen reasonably sharp declines in the Arctic, and only recently have we seen that also maybe starting to happen in the Antarctic as well," says Otago University School of Surveying professor Greg Leonard.

NASA satellite data reveals after three decades of slow growth, sea ice around Antarctica hit a record high in 2014. But then over the space of three years, levels plummeted sharply with Antarctica losing two-million square kilometres of sea ice.

"There have been a number of attempted explanations but definitely no consensus view yet," says Dr Claire Parkinson, from NASA's Goddard Space Flight Center.

Scientists aren't sure whether the dramatic drop is a temporary blip, with sea ice levels rebounding. However any change can have a big impact on the wildlife.

"The sea ice cover affects birds, it affects whales, it affects seals, it affects little organisms that actually live in the ice so the little organisms - their entire life is sometimes lived with in the ice," Dr Parkinson says.

Otago University researchers are trying to dig deeper into the figures. Next summer they'll be heading down measuring the thickness of the sea ice and studying the interactions between the Antarctic ice shelves.

"Sea ice is as we know already floating in the ocean, so it melting doesn't contribute directly to sea level rise," says Prof Leonard. "But it also plays a role in buttressing the ice shelves around Antarctica."

It's a wait and see if the sea ice melt in Antarctica is for real and a serious concern for our future climate.