New Zealand: How climate change is affecting poles

New Zealand scientists said Thursday they had made a breakthrough in understanding how large waves were breaking up Antarctic sea ice, which could change understanding of how climate change is affecting the two global ice caps.
Studies by the government's National Institute of Water and Atmosphere Research (NIWA) showed that large waves those bigger than 3 meters can break sea ice over greater distances than previously believed.
They said this process could be "the missing science" that explained the increase in Antarctic and rapid decrease in Arctic sea ice.
The findings were in contrast to the predictions from climate change models that Antarctic sea ice should have already begun retreating and could explain the accelerating loss of Arctic sea ice, NIWA scientist Dr Alison Kohout said in a statement.
"In the Arctic there is a lot of evidence of sea ice retreat, yet scientists have been unable to reproduce the speed of sea ice retreat in their modeling. This suggests something is missing from the models," she said.
Sea ice played a critical role in moderating the global climate system and the state of the sea ice was an indicator of how climate was changing around the poles.
The Southern Ocean was continually generating large and unforgiving swells that broke the sea ice apart, removing the barrier between the ocean and atmosphere.
The breakthrough was due to new technology that enabled scientists to collect more and better data about large waves, NIWA 's Dr Mike Williams said in the statement.
"When the experiments required for this research were last carried out in the 1970s and 1980s, people needed to be sitting on the sea ice to take measurements and that meant they couldn't be out there when the big waves came through," Williams said.
"Now we have autonomous equipment that can be out there during storms and that's what gave us the ability to get the new data."
The findings also had the potential to be used as a predictive tool for ship navigation through sea ice, he said.