Streams of hot air pierce the Antarctic sea ice
A team of scientists focused on the study of long and intense streams of hot airknown as atmospheric riversrelated to their ability to create huge openings in the Antarctic sea ice, known as polynya.
The atmospheric rivers in the Weddell Sea
In particular, the research focused on the Weddell Sea region, in the Southern Ocean near Antarctica, where these holes in sea ice they rarely develop during the winter.
In this area the first hole was observed in 1973. It hadn’t happened since then until early spring 2017. Another event was then observed just this winter.
Holes in the ice are a consequence of atmospheric rivers
In a previous study on the subject, researchers found that frepeated intense atmospheric flows, which took place from late August to mid-September 2017, played a crucial role in the formation of the sea ice hole. These rivers indeed push the warm, humid air from the coast of South America up to the polar environment, heating the surface of the sea ice and making it vulnerable to melting.
The co-author Kyle Mattingly, a postdoctoral researcher at the Rutgers Institute of Earth, Ocean, and Atmospheric Sciences, explains that “polynyas strongly influence the physical and ecological dynamics of the Southern Ocean. In fact, they act as gigantic ‘windows’ in the sea ice which allow large amounts of heat to move from the ocean to the atmosphere, changing regional and global ocean circulation. They also influence the timing and extent of phytoplankton blooms, which are the basis of the marine food web. Our study will pave the way for a greater understanding of climate variability and climate change in these regions “.
This new study therefore shows the effects of atmospheric rivers and polynyas on Antarctic sea ice. Atmospheric rivers are thousands of kilometers long and the holes in the ice cover huge surfaces.
Climate change will lead to melting of Antarctic sea ice
These events could significantly affect the melting of the West Antarctic ice sheet, located on the mainland. The ice sheet in this region is melting rapidly, contributing to global sea level rise. If the entire Antarctic ice sheet melted, the ocean level would rise of about 60 metersthreaten coastal communities around the world, especially in low-lying areas.
Climate change will make atmospheric rivers more intense and more frequent which will be more effective in moving high levels of water vapor to the Southern Ocean and towards the Antarctic continent, together with the increase in rainfall intensity. This will dangerously increase the formation of holes in the ice, which will lead to an acceleration in the melting of the shell.
Image by Sarah N from Pixabay