Aug 18, 2019 | Updated: 07:24 AM EDT

Peering into Deep Dark Pits in the Antarctic

Jul 18, 2019 09:03 AM EDT

Polynya off the Antarctic Coast
(Photo : NASA's Earth Observatory)
Polynya off the Antarctic Coast

Every year, from June to September, about seven million square miles of ice covers Antarctica. Over the past several decades, scientists were able to notice jagged blue-black cavities known as polynyas.

In 2016 and 2017, the jagged holes in the Antarctic were more than 13,000 square miles in width. The polynyas persist even in a freezing temperature of -58°F

However, even if these dark pits occur every year, scientists still point out that there is a lot that is unknown.

For example, whether these jagged holes affect the atmosphere is still a big question. Some scientists raised the concern that the holes might be releasing carbon dioxide that has been stagnant and stored in the deep ocean. It also raises questions as to what this means for the marine life that dwells inside the dark pits.

Perhaps, another big question that merits a lot of research is the origin of these polynyas. 

Ethan Campbell, the study's lead author and a graduate student in oceanography at the University of Washington, concluded that polynyas occur as a combination of different factors happened at the same time.

When the scientists investigated, they found out that warmer and saltier water from deeper depths is pushed to the surface. Campbell says that a "deep, violent, and vertical" mixing happens when storms blow in.

NASA added that this pattern loops again and again. When springtime comes, the surrounding air warms a little, and fresher and lighter water would appear on top.

Previous research on the 2017 Maud Rise polynya has similar results as this new study. Campbell added that in this phenomenon, storms are essential.

Campbell's team found out that polynyas occur as a number of elements work in conjunction. The said elements include the warm, salty water that rushes to the surface, which is cooled down by the blowing wind, and later sinks into the depths of the sea. This process goes on in a constant churn.
Co-author and University of Washington oceanographer, Stephen Riser, added that all these factors should be present for jagged holes to occur.

Still, scientists are on a quest to find out more about polynyas. Some speculate that climate change has an effect on the occurrence of these jagged holes. Especially that melting glaciers are adding to the freshwater volume, slowing down the churning action within the pits.

©2017 All rights reserved. Do not reproduce without permission. The window to the world of science times.
Real Time Analytics