MELBOURNE, June 10 (Xinhua) -- Antarctic sea ice is melting significantly faster in summer due to the combined effects of ocean waves, surface flooding and algal growth, new Australian-led research has revealed.
Scientists found that waves entering ice-covered regions do more than break up ice floes. They wash away the bright snow cover that shields the underlying ice from sunlight, flood the surface with seawater, and create "wave ponds" that absorb more solar heat, accelerating melt from above, according to the study published in The Cryosphere on Tuesday.
Moreover, snow-free ice and wave ponds become algae oases, turning green and absorbing more solar heat, said the team led by Rob Massom from the Australian Antarctic Division, the study's corresponding author.
The research identifies these wave-driven processes that cause the surface of the sea ice to melt as a "missing link" in understanding what's driving the increasing Antarctic sea ice melt each summer, said a summary of the study published on The Conversation website.
Researchers estimate that wave-induced flooding, ponding, and "pulverization" are "extraordinary accelerators" of ice melt, increasing ice thinning by more than 4 cm per day, with algal greening adding 1 cm daily.
"We propose that this positive feedback is strengthened by algal greening that further darkens the ice, leading to further absorption of sunlight and melting," the authors wrote.
The study shows Antarctic sea ice can turn into "rafts of rotting floes" or "an icy green slush" when it interacts with waves in the Southern Ocean, one of the world's most storm-driven regions.
Scientists warn that intensifying winds and waves linked to climate change could amplify these effects, with implications for global climate and marine ecosystems. ■
