Thwaites glacier's accelerated melting in Antarctica surprises scientists: Here's why
The Thwaites glacier in Antarctica, ominously known as the "Doomsday Glacier," is melting at a faster pace than scientists previously estimated. Recent findings published in the Proceedings of the National Academy of Sciences, reveal that warm ocean water is being forced several kilometers underneath the glacier, causing "vigorous melting." This unexpected phenomenon challenges prior beliefs that the boundary where the glacier meets the seafloor was fixed.
Saltwater intrusion fuels rapid melting
According to study co-author Eric Rignot, the saltwater intrusion is causing the glacier to melt over larger distances than previously thought. "The water is able to penetrate beneath the ice over much longer distances than we thought," he said. This revelation has sent a "shock wave" through the scientific community, as it indicates that the melting process could potentially raise global sea levels by over two feet, if Thwaites were to completely melt.
Satellite data reveals unprecedented glacier changes
To study the Thwaites Glacier, which is roughly the size of Florida, researchers utilized space-based imaging from satellites known as ICEYE. These satellites orbit above Earth's polar caps and have provided extensive data, that allowed researchers to create a 3D view of all tidal forces affecting the ice sheet. The data revealed significant information about the glacier's grounding line - a region where the ice is no longer in contact with the seafloor and is exposed to ocean water.
High tides expose more ice to warming
The data from ICEYE satellites revealed that high tides are forcing warm ocean water beneath the glacier, exposing huge amounts of ice previously thought untouchable to warming. Rignot explained that seawater travels almost 6.4km in a 12-hour cycle, flushing out any freshwater melted from the glacier and replacing it with seawater, which has a lower freezing point due to its high salt concentration. This process of widespread seawater intrusion is tipped to increase projections of sea level rise from Antarctica.
Implications for other glaciers and coastal communities
These findings have serious implications not only for Thwaites but also for other glaciers in Antarctica. Co-author Christine Dow expressed concern about underestimating the speed of these changes, stating, "Thwaites is the most unstable place in the Antarctic and contains the equivalent of 60cm of sea level rise." She warned that faster-than-expected changes would be devastating for coastal communities around the world.
Call for further research on Antarctic glaciers
Rignot hopes these alarming findings will spur further research into the conditions underneath Antarctic glaciers, and lead to improved ice sheet models. He believes that incorporating this type of ocean-ice interaction into models will help reproduce past events more accurately, and increase confidence in future projections. This could provide crucial insights for understanding and mitigating the impacts of climate change on global sea levels.
