Antarctica’s ice shelves are not just thinning from warm air above, they are being attacked from below by hidden turbulence that behaves like underwater storms. New research shows that these swirling currents can rapidly accelerate melting at the base of the ice, turning what once looked like a slow, predictable decline into something far more volatile and difficult to manage.
Instead of a steady drip, the underside of the ice is experiencing pulses of heat that can triple melt rates in a matter of hours, reshaping how I think about future sea level rise and coastal risk. The discovery that these under-ice storms are supercharging melt rates forces scientists and policymakers to rethink what “safe” timelines look like for communities that depend on a stable Antarctic.
What scientists mean by “under-ice storms”
When researchers talk about storms beneath the ice, they are not describing weather in the usual sense, but compact, swirling currents that behave like miniature cyclones in the ocean. These features, known as submesoscale eddies, form where layers of water with different temperatures and salinities collide, creating sharp fronts that twist and fold like atmospheric storm systems. Under Antarctic ice shelves, those eddies can be squeezed into narrow cavities, where they slam warm water against the ice base and pull colder meltwater away, constantly refreshing the heat supply.
In recent work, UC Irvine and NASA researchers identified these stormlike circulation patterns beneath Antarctic ice shelves and showed that they are far more energetic than the smooth flows used in many earlier models. Instead of a gentle, laminar current, the underside of the ice is riddled with sharp, spinning motions that can focus heat on specific patches of ice, carving channels and pits that destabilize the shelf. That shift in understanding, from broad flows to intense small-scale storms, is central to why melt rates are turning out to be so much higher than expected.
How tiny motions unleash intense melting from below
The key to the new findings is that even “tiny” motions in the ocean can have outsized consequences when they occur in the tight space between ice and water. In that narrow gap, a small increase in turbulence can strip away the thin, cold boundary layer that normally insulates the ice from warmer water below. Once that protective layer is disrupted, heat can rise rapidly under the Antarctic ice, and the melt rate jumps. What looks like a subtle change in current speed or direction becomes a powerful mechanism for delivering warmth directly to the ice base.
One study found that these small-scale motions trigger intense melting from below by pumping relatively warm deep water into contact with the ice and then flushing out the resulting freshwater so the process can repeat. The result is a feedback loop in which heat rising under Antarctic ice is constantly renewed rather than being used up. That mechanism helps explain why some shelves are thinning faster than regional average temperatures alone would suggest, and why local geometry and circulation matter so much for predicting future loss.
Tripling melt rates in a matter of hours
Perhaps the most startling result from the new research is just how quickly these under-ice storms can change the pace of melting. Instead of a gradual response to seasonal warming, scientists are seeing short, intense bursts of activity where melt rates spike severalfold over very short periods. In some simulations and observations, stormlike submesoscale currents under Antarctic ice shelves can triple melt rates within hours, turning what might have been a stable ice base into a rapidly eroding surface.
Those rapid pulses of erosion mean that the structural integrity of an ice shelf can deteriorate in fits and starts, rather than in a smooth, predictable way. A shelf that appears relatively stable one week can be riddled with new channels and thinning zones the next, especially where these storms focus their energy along ridges and crevasses. The finding that New stormlike currents can drive such abrupt changes helps explain why some parts of the Antarctic coastline are losing ice at alarming rates, even when surface conditions do not look dramatically different from year to year.
Inside the “doomsday” glacier’s hidden turbulence
Nowhere are the stakes of this process clearer than at the so-called “doomsday” glacier, where a massive ice shelf holds back a vast reservoir of inland ice. To understand what is happening beneath that shelf, researchers deployed an autonomous float that drifted under the ice and recorded temperature, salinity and current data. With the data later gathered from the captured float, With the research team, including Cathrine Hancock at Florida State University and her colleagues, was able to reconstruct a picture of violent under-ice storms that were far more energetic than expected.
The float’s measurements showed that these storms were funneling warm water into narrow channels and cavities, where it chewed away at the ice shelf from below. That undercutting weakens the shelf’s grip on the seafloor and can hasten the retreat of the grounding line, the point where the ice lifts off the bedrock and begins to float. Because the glacier in question is a major contributor to potential sea level rise, the discovery that undersea storms are actively eroding its ice shelf suggests that future ocean-driven changes in Antarctica could drive higher sea level rise than we currently expect.
Why a warming planet breeds more under-ice storms
The emergence of these storms is not happening in isolation from the broader climate system. As Earth warms, the Southern Ocean is absorbing much of that excess heat, and the pattern of sea ice cover around the continent is changing. Less sea ice means the ocean surface is more exposed to wind for longer periods, which injects more energy into the upper ocean and helps generate the sharp fronts and eddies that feed submesoscale storms. Longer ice-free seasons also give those storms more time each year to interact with the ice shelves from below.
Researchers warn that as Earth continues to heat up, these ocean storms could become more frequent and intense, particularly in regions where sea ice retreats earlier and returns later. That trend would give the turbulent currents more opportunities to reach the base of glaciers and deliver warm water into vulnerable cavities. One study notes that As Earth warms, the combination of reduced sea ice coverage and longer open-water seasons is likely to amplify the role of these storms in melting Antarctic glaciers from below. That link between global warming, sea ice loss and under-ice turbulence is one of the clearest ways in which human-driven climate change is reshaping the Antarctic system.
Rewriting models of Antarctic ice loss
For years, many ice sheet models treated the ocean beneath ice shelves as relatively smooth and predictable, averaging out the small-scale motions that are now proving so important. The new research shows that this simplification can dramatically underestimate melt rates, especially in regions where submesoscale storms are active. When those storms are included, the simulated ice shelves thin faster, grounding lines retreat more quickly and the projected contribution to sea level rise increases.
Co-author Yoshihiro Nakayama, an assistant professor of engineering at Dartmouth, has described how he Initially set out to understand relatively modest circulation features, only to find that the storms at the ocean’s subsurface were a missing piece in previous models of ice loss. Incorporating these dynamics requires high-resolution simulations and significant computing power, including resources from the NASA Advanced Supercomputing Division, but the payoff is a more realistic picture of how quickly Antarctic ice can respond to ocean changes. For policymakers and coastal planners, that refinement is not an academic detail, it is a direct input into how fast sea levels might rise in the coming decades.
From hidden storms to visible glacier retreat
The effects of these under-ice storms are already visible in the rapid retreat of some Antarctic glaciers. Earlier this year, scientists reported that one glacier had experienced the fastest retreat in modern history, with its ice front pulling back dramatically over a short period. The glacier in question is a smaller cousin to some truly gigantic, I mean size of the island of Britain, glaciers in Antarctica that most people have never heard of, but its behavior is a warning sign. However, the processes driving its retreat, including ocean-driven melting at the grounding line, are likely to be at work beneath those larger glaciers as well.
Scientists now see these hidden storms as an additional attack on the grounding line, working alongside warm water intrusions and changing wind patterns to destabilize the ice. One analysis notes that storms could be adding to this attack by focusing melt at critical points where the ice meets the bedrock. That study argues that violent storms hidden under the ice provide a compelling mechanism for tying together observed thinning, grounding line retreat and the broader decline of Antarctic ice shelves. The rapid retreat of glaciers like Hektoria is therefore not just a local curiosity, but part of a larger pattern in which under-ice turbulence is accelerating the loss of grounded ice.
Why Antarctic melt matters far from the poles
For people living thousands of kilometers away from the Southern Ocean, it can be tempting to see Antarctic melt as a distant problem. In reality, the ice lost at the bottom of the world translates directly into higher seas that threaten homes, infrastructure and freshwater supplies in coastal cities. Why is Antarctic melt concerning? Because even modest additional sea level rise can turn once-in-a-century floods into regular events, overwhelm drainage systems and push saltwater into aquifers that millions of people depend on.
One climate scientist put it bluntly when asked about the broader stakes: the melting polar ice is not just a remote concern, it is a threat to coastal communities that are already grappling with heat waves, storms and air pollution in their own towns. That warning, captured in a report that asked Why Antarctic melt is so worrying, underscores how the physics of under-ice storms connect to everyday choices about where to build, how to insure property and which climate policies to prioritize. As the science of submesoscale storms sharpens our picture of future sea level rise, it also sharpens the choices facing governments and communities that still have time to prepare, but not nearly as much time as they once thought.
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