Past Global Flood Reveals Antarctica’s Ice Sheet Vulnerability
The Eemian Mystery
Between 116,000 and 129,000 years ago, sea levels were significantly higher than today, submerging coastal areas and entire islands. The cause of this rise during the Eemian period has been a mystery, but new research suggests it was triggered by the collapse of the West Antarctic Ice Sheet.
Greenland Exonerated
Scientists initially believed that the Greenland Ice Sheet was responsible for the sea level rise during the Eemian. However, recent geological evidence indicates that Greenland’s ice remained intact, clearing it of blame.
West Antarctica’s Role
The West Antarctic Ice Sheet became the prime suspect due to its massive size and instability. To investigate its role, glaciologists analyzed sediment cores drilled off the coast of the ice sheet. They found that during the Eemian, material from the Amundsen province and Pine Island Glacier areas gradually disappeared, leaving only silt from the Antarctic Peninsula.
Ice Sheet Collapse
This finding suggests that the ice in Amundsen and Pine Island Glacier areas ceased flowing or melted, while the glaciers in the Antarctic Peninsula persisted. The researchers concluded that the West Antarctic Ice Sheet had collapsed, eroding its ability to contribute sediment to the marine environment.
Temperature Sensitivity
The collapse of the West Antarctic Ice Sheet highlights its vulnerability to temperature changes. This raised concerns because the ice sheet is currently showing signs of stress. However, it’s important to note that the Eemian period is not an exact parallel to today’s climate change, as it was driven by natural factors rather than human activities.
Signs of Instability
Despite the differences between the Eemian and present-day climate, Antarctica is exhibiting signs of instability. The West Antarctic Ice Sheet has lost three trillion tons of ice since 1992, with ice losses accelerating in recent decades.
East Antarctica’s Concerns
Not just the West, but also the East Antarctic Ice Sheet, long considered stable, is showing signs of ice loss. Glaciologists have observed thinning and accelerating flow rates of glaciers in Vincennes Bay and the massive Totten Glacier. These systems hold enough ice to raise sea level by 30 feet.
Impact on Sea Level
According to NASA, Antarctic ice melting has already contributed to a 0.3-inch increase in global sea levels since 1992. If all of Antarctica’s ice melted, sea level would rise by an immense 190 feet. While this may seem extreme, studies suggest that burning all available fossil fuels could potentially melt the entire ice cap.
Further Research
Researchers are planning to drill additional sediment cores off Antarctica to gain more insights into the Eemian period. Their findings will help refine our understanding of the vulnerability of Antarctic ice sheets to climate change and its potential consequences for sea level rise.