Ross Sea ice could have dramatic impact on NZ
Thursday 21 Nov 2013 5:43 p.m.
New Zealand scientists in Antarctica are trying to find the missing link into why the ice in the Ross Sea is extending during climate change.
If sea ice does start to disappear and melt, sea levels are certain to warm and rise, which could significantly influence the climate in New Zealand.
Scientists Wolfgang Rack and Pat Longhorne are trying to find out if the sea ice is melting away.
The thickness of the solid sea ice is about two metres. Scientists have used an electromagnetic induction device under a helicopter to take measurements from above. A similar device is also towed behind Ski-Doos on the ground, validating another set of measurements taken by satellite.
"We know from the Arctic that the sea ice is shrinking dramatically and we also expect that to happen here in Antarctica. We need to find out the tipping point when is this going to happen," says Mr Rack.
"It is by far the biggest challenge that has faced human beings living on the planet," says Mr Longhorne.
Sea ice in Antarctica melts from the bottom up and while it's extending out to sea. What scientists don't know, is what impact Antarctica's giant ice shelf is having on the sea ice thickness.
With oceans warming around the world, National Institute of Water and Atmospheric Research (NIWA) divers collect critical algae samples from under the sea ice.
"Algae is the base of the food chain in that part of the world, so if they are affected in one way or another, there will be implications to the way the rest of the community under the ice works," says NIWA marine ecologist, Voda Cummings.
That would include penguins and seals, and it will also affect New Zealand.
"If sea ice disappears, we will observe more warming and that will influence significantly the climate in New Zealand," says Mr Rack. "Antarctic ice sheet will shrink even faster and contribute to sea level rise."
Just how fast the sea ice is melting will be critical for generations to come.