Rising sea levels caused by climate change threatens the homes and livelihoods of millions of people who live along the coast. According to professor David Holland, the main sources of water that could lead to elevated sea levels are the melting ice sheets of Antarctica and Greenland. Holland and a member of his team from the Center for Global Sea-Level Change (CSLC) at NYU Abu Dhabi have recently published a paper in Nature which found that one of the most sensitive and critical areas of the Earth’s ice in West Antarctica is being affected by changes in the north and tropical Atlantic, which has been warming for more than 30 years.
The team’s conclusion is surprising because initially there is no reason to think that the far-off north and tropical Atlantic would affect Western Antarctica. But this seems to be the case, and their analysis demonstrates the complexities of global climate, says Holland, professor of math and atmospheric ocean science and head of CSLC. The paper’s lead author, Xichen Li, is a doctoral student at the Courant Institute of Mathematical Sciences and an affiliate of CSLC.
“To date, the focus of our work has been studying the melting of ice sheets on location by carrying out field programs in Antarctica and in Greenland,” says Holland, a professor at the Courant Institute. But for the paper published in Nature, the researchers wanted to understand how warm ocean water was being directed to West Antarctic glaciers in the first place.
Scientists have long known that the climate of the Antarctic Peninsula in West Antarctica is affected by changes in the Pacific Ocean, and that changes in the Pacific cause short-term changes to the climate of the peninsula. But fluctuations in the Pacific couldn’t account for the warming of the peninsula or for the redistribution of sea ice around it. So for this paper, researchers focused on the Atlantic, which had been overlooked as a force behind Antarctic climate change.
According to Holland, it is remarkable that the recent 30-year trend in North Atlantic Ocean warming is driving climate change in West Antarctica. And it’s worrying that “West Antarctica is precisely the most sensitive place on Earth for future sea-level change,” he adds. “This opens the possibility of significant sea-level change of a meter or so in the next century, which could have a huge impact on low-lying coastal areas.”
Additional authors of the paper are Courant assistant professor Edwin Gerber and postdoctoral fellow Changhyun Yoo.