Antarctica Gained 695 Billion Tons of Ice While Glaciers Around the World Melted — Here’s Why

New research published by Nature has confirmed that the East Antarctic Ice Sheet gained an astounding 695 billion metric tons of ice between 2021 and 2023, despite continually rising global temperatures.

In the modern age of climate change, an actual gain in ice — especially one of the scale seen in Antarctica — is far from the status quo. In other regions around the world, ice loss due to glacial melt has continued to persist at an alarming rate.

Between 2021 and 2024, an average of 24.5 billion tons of previously permanent ice melted every year across Washington, Montana, British Columbia, and Alberta. Over in the Alps, Swiss glaciers were observed to have lost over 10% of their total volume in just a two-year period (2022-2023). Finally, in perhaps the most striking example, Greenland lost an average of 279 billion tons of ice every year between 2002 and 2020 — enough water to fill Lake Erie more than 10 times over across that 18-year period.

• Related: The Glaciers Aren’t Melting—They’re Collapsing

So why, then, during a period of such dramatic glacial retreat, did Antarctica see such a massive gain in ice? Counterintuitively, the observed 695 billion tons of new ice are thought to have been caused by a warming event that took place thousands of miles from the South Pole.

Along the equator, where the eastern Indian and western Pacific oceans meet, sits one of the warmest bodies of water found anywhere on Earth. Between 2021 and 2023, this patch of water grew even warmer than its already-high normal temperatures, creating what’s called a tropical warm pool, which set off a climatic domino effect.

The warm water had a dramatic effect on the atmosphere above it, creating a ripple of pressure waves that traveled all the way down to Antarctica. This caused the formation of a low-pressure system off the southern coast of Australia, and a high-pressure system over East Antarctica, which in turn directed heavy moisture — in the form of atmospheric rivers — toward the continent. When this moisture meets frigid Antarctic air, it falls to the ground as snow.

• Related: New 3D Algorithm Reveals Atmospheric Rivers Fuel Antarctica’s Snowfalls

More snowfall means more mass for the ice sheet, which is exactly why Antarctica gained such a large volume of ice during an era when it typically loses around 140.5 billion tons of ice per year. It’s important to note this is not a sign that human-caused climate change will continue to boost Antarctic ice well into the future. Surprisingly, anthropogenic warming was not primarily responsible for the tropical warming event that caused increased Antarctic precipitation — studies show human activity accounted for only 9% of the snowfall anomaly.

The tropical warm pool observed here is actually a naturally occurring event that takes place roughly once every decade. This means the 695 billion tons of gained ice does not signify the reversal of an overall trend, but rather a brief reprieve from the troubling trajectory of a rapidly deteriorating Antarctic.

As exciting as gains in ice volume may be, especially amid glacial recession and shrinking winters seen around the world, this study shouldn’t necessarily be taken as cause for celebration — but rather as insight into the complex functioning of the world’s largest freshwater supply as we continue to grapple with our changing climate.