As global temperatures climb and seas continue to rise, oceanographer Lynne Talley warns that the accelerating melt of Antarctic ice threatens to erase entire island nations within decades. From her decades of research in the Southern Ocean, Talley has traced how warming waters and shifting circulation patterns are destabilizing the planet’s climate system — and she says the warning signs are now unmistakable.
At the 2025 Comer Climate Conference in western Wisconsin, Talley joined fellow scientists to present new evidence that the pace of ocean warming and ice loss is quickening, with consequences already unfolding across the globe.
The warming of the Southern Ocean and melting ice have bot been accelerating, according to NOAA and NASA and Tally has been studying these patterns for decades as an ocean expert and professor at the Scripps Institution of Oceanography at the University of California.
Talley recently presented her research findings to fellow climate scientists at the 2025 Comer Climate Conference in western Wisconsin. At the conference, scientists presented research on ice sheet behavior, ocean circulation and climate shifts linked to more extreme weather. Presentation topics included the rapid retreat of Antarctic and Greenland ice sheets and the impacts of changing ocean and atmospheric systems on global climate and sea level.
Speakers, including Talley and Penn State glaciologist Richard Alley, emphasized that human action has the power to influence outcomes of climate change, underscoring both the urgency and possibility of climate mitigation.
Talley’s presentation, “Southern Ocean Overturning Circulation: ocean carbon motivations and zonal asymmetries,” discussed how carbon dioxide exchange between the atmosphere and the Southern Ocean leads to increasing water temperatures, changing circulation patterns and melting sea ice. The carbon exchange in all oceans has mitigated for atmospheric
global warming by absorbing much of the carbon dioxide emissions from fossil fuels into the
oceans.
In certain areas of Antarctica, wind-driven upwelling lifts deep, sometimes warm waters toward the surface, a process central to both climate regulation and ice shelf melting, Talley said. Warm circumpolar water rises beneath the ice shelves of the West Antarctic Ice Sheet, melting the ice from below. The land ice sheets melt, and this process, coupled with thermal expansion, causes ocean levels to rise.
The most dire prediction of Talley’s research is that the entire West Antarctic Ice Sheet could melt, causing ocean sea level to rise and eventually overtake low-lying island nations in the Pacific and elsewhere. “It’s like the water rising slowly around your house,” Talley said. “Eventually it comes across the threshold, and you can’t turn that around.”
Obtaining prompt, accurate data about ocean dynamics is crucial to detecting changing sea patterns. Talley uses human-sized autonomous robotic instruments, called floats, to measure temperature, chlorophyll, oxygen and salinity in the depths of the Southern Ocean. Floats dive thousands of meters below the ocean’s surface to follow currents and record data.
Oceanographer and Professor Stephen Riser of the University of Washington, one of Talley’s frequent collaborators, said floats are a carbon-efficient way to obtain ocean data, as the floats have a small carbon footprint. Additionally, for the cost of one large ship expedition, they can purchase hundreds of floats, he said. A float can collect data for over five years and during extreme weather events when ships may not be able to safely proceed.
In terms of understanding changes in the Southern Ocean, Riser emphasized the complex dynamics of climate change, including changes in wind speed and direction, changes in the amount of precipitation in winter, and other factors working together to produce unexpected or complex results.
“All of these things work together. It’s not just as simple as things are getting warmer and the ice is melting,” Riser said. “There are other things in there like wind and things like El Nino. But the general trend I would, I’m sorry to say, in the next decade or two, is probably leading to less sea ice, [and] climate models will show that for sure.”
Ben Taylor, a Scripps PhD student that has worked with Talley, participated in a research trip to place floats into the ocean. He describes the technology as crucial to understanding how the ocean’s heat and carbon stores are changing, the strength of algae life, and other chemical parameters of ecosystemhealth.
In October 2020, the U.S. National Science Foundation approved a $53 million grant for Scripps Institution and four academic collaborators to build and use a 500-float fleet to obtain data from the Southern Ocean and supply it to scientists globally. According to Taylor, recent federal funding cuts for scientific research have caused fear that the grant will not be renewed. As the floats provide crucial data for scientists all over the world, Taylor said he hopes other countries will supply funding to fill any gaps left by the U.S.
Alley, the emcee for the conference, estimates that losing the Western Antarctic Ice Sheet will cause 11 feet of sea level rise. Many islands and coastal regions in the U.S. and elsewhere would be underwater at that level of inundation.
However, these results are not guaranteed, and greatly depend on the policy choices of the next few years. Alley recently co-authored a paper that argues if global warming is kept below two degrees Celsius, the ice sheet can be saved.
Temperature rise has currently reached 1.6 degrees Celcius, already above the 1.5-degree set by the international Paris Agreement that the Trump administration abandoned in 2016 and 2024.
Talley said she advocates for a complete phase-out of fossil fuels, and zero emissions, as ways to mitigate climate effects and prevent irreversible damage to the planet. “That’s it. It’s very simple,” Talley said. “Stop warming the planet. It won’t cool.”
