Antarctica is known for losing ice. But between 2021 and 2023, something very unusual happened: the Antarctic Ice Sheet gained about 695 billion tons of mass, a historic anomaly spanning more than two decades of continuous satellite monitoring.
Now, scientists from the Chinese Academy of Sciences and the University of California, Santa Barbara have traced that temporary gain to a surprising source: unusually warm ocean water thousands of miles away.
The research, which was recently published in the journal Nature, found that sustained warming where the western Pacific meets the eastern Indian Ocean triggered a large-scale pattern of atmospheric waves capable of transmitting changes in weather and circulation across enormous distances.
The resulting changes in atmospheric circulation redirected moisture toward East Antarctica. Much of that moisture arrived in narrow corridors called atmospheric rivers, which carried water vapor from the mid-latitude Indian Ocean. When that moisture reached the frigid Antarctic continent, it fell as heavy snow, adding enough mass to temporarily offset ice losses elsewhere.
But this does not mean Antarctica's long-term ice loss has been reversed. Over the past two decades, the ice sheet has lost an average of about 140 billion tons of ice each year.
The study reveals just how interconnected Earth's climate system can be. Conditions in a warm tropical ocean can influence atmospheric circulation thousands of miles away, and temporarily change the balance of ice on the other side of the planet.
**********
References:
Multiyear tropical warm pool warming drives slowdown in Antarctic mass loss
