New research has examined the reason behind the rapid retreat of Antarctic sea ice. University of Washington researchers established that the puzzling phenomenon can be explained by simple physics.
In contrast to the North Pole, Antarctic ice bounces between growing and melting. From March to October, Antarctic sea ice grows by six times to become larger than Russia. Then, the ice melts drastically around December when Antarctica experiences daylight around the clock.
Published in “Nature Geoscience,” the study explains that this occurrence is natural. Lead author Lettie Roach, who worked on the study as a postdoctoral researcher, says the situation is quite simple to explain.
“In spite of the puzzling longer-term trends and the large year-to-year variations in Antarctic sea ice, the seasonal cycle is really consistent, always showing this fast retreat relative to slow growth,” said Roach. “Given how complex our climate system is, I was surprised that the rapid seasonal retreat of Antarctic sea ice could be explained with such a simple mechanism.”
Previous studies explored the possibility of wind patterns causing the irregular seasonal sea ice cycle. The new research shows that Antarctic sea ice simply melts faster in midsummer with more sunlight. Researchers used global climate models and built a physics-based model to help prove that seasonal solar radiation patterns facilitate the quick melting of Antarctica ice.
“I think because we usually expect Antarctic sea ice to be puzzling, previous studies assumed that the rapid seasonal retreat of Antarctic sea ice was also unexpected — in contrast to the Arctic, where the seasons of ice advance and retreat are more similar,” Roach said.
Roach says that the Antarctic sea does not follow a similar pattern to the Arctic sea. The researchers are exploring the reason why the two polar points behave differently.
“Our results show that the seasonal cycle in Antarctic sea ice can be explained using very simple physics. In terms of the seasonal cycle, Antarctic sea ice is behaving as we should expect, and it is the Arctic seasonal cycle that is more mysterious,” Roach added.
Lead image via Pixabay