Scientists have discovered a waterway roughly similar in size to the Murrumbidgee River that once dominated West Antarctica. This finding offers a rare glimpse into the continent’s topography long before it became covered in massive ice sheets. That makes two recently detected rivers under Antarctica in the past year.
An Insightful Exploration
Geological excavations in the West Antarctica region have uncovered the remains of an ancient river system that flowed around 40 million years ago. The exploration was conducted by researchers from the Alfred Wegener Institute in Germany, and the findings were published on June 5 in the Science Advances journal.
The recovered sediment from the exploration sites indicate the river stretched approximately 1,500 kilometers, draining from the Transantarctic Mountains into the Amundsen Sea. For context, that’s comparable to the dimensions of the 1,485 km Murrumbidgee River in New South Wales.
The findings also suggest the ice-covered continent had a temperate climate with dense forests and a vast network of waterways during the Eocene age some 34 million years ago. This era preceded the gradual glacial buildup that resulted in Antarctica’s current state.
Study author Professor Cornelia Spiegle described the scene as having a 19° Celsius water surface temperature during summer and swampy conditions. The river presumably meandered through vast coastal plains with wetlands lined along the banks. In terms of wildlife, she suggested the area may have been home to giant penguins, which indicates the land rested above sea level during that period.
The Role of Climate Change
A significant climate event occurred in Antarctica millions of years ago, sparking the transition to its current icy conditions. Researchers believe these incidents involved a marked increase in carbon dioxide nearly twice as much as today’s levels.
Study co-author Dr. Johann Klages believes these insights present a compelling benchmark for understanding how future scenarios might unfold. There is also no ruling out the possibility that such an event may occur in the future, given there’s already a precedent. As human-driven climate change continues to speed up the rate of greenhouse gas emissions, he suggested comparable levels may start to manifest globally within the next 150–200 years.
What’s the Climate Crisis in the Southern Polar Region?
Spanning 14.2 million km2, Antarctica is the fifth-largest continent on Earth — nearly twice the size of Australia. About 97.6% of this area is covered in 2,160-meter-thick ice sheets. This buildup represents 90% of the planet’s available ice, highlighting the region’s strategic relevance in regulating global temperatures.
As the planet heats up, this ice repository is melting faster than ever, causing a flurry of potentially irreversible changes. Rising sea levels are an immediate concern, as it impacts coastal drinking water supplies and ecosystems.
These conditions are also rapidly changing the ocean currents — the vast deposits of freshwater from the ice react poorly with the salty, denser seawater. This reaction contributes to the frequency and severity of erratic natural events like tropical storms and heavy floods. At the northern end, melting ice shelves along the Arctic are rendering polar bears and other endemic creatures homeless, further increasing their risk of extinction.
How Many Rivers Are in Antarctica?
The region has no rivers in the sense of the word, as the waterways there are a result of icemelt that formed massive puddles. However, two water bodies have “river” in their names — Alpha and Onyx. There’s also no telling how many current and prehistoric subglacial rivers exist without further study.
Interestingly, the Alfred Wegener Institute team’s discovery comes mere months after scientists uncovered another ancient river system — this time in Eastern Antarctica. The study was conducted by researchers from Durham and Newcastle Universities in the UK and revealed a hidden river landscape from over 14 million years ago.
Echoing the sentiments of his German counterparts, lead author Professor Stewart Jamieson expressed worry over the long-term impact of global warming on the region. He believes rising temperatures could cause rapid glacial melt and increase the risk of sustained ecological damage as they did in the last few million years.
How Do Scientists Explore Antarctica?
Human deep-sea explorations are virtually impossible, as the risk of physical injury from the crushing water pressure increases at 40 meters, whereas the ocean depth goes down over 7,000 meters.
In the East Antarctic exploration, the research team relied on powerful satellite imagery and radio-echo sounding data to map the subsurface beneath the ice sheet. This technology helped the team uncover a 32,000 km2 preserved landscape, implying that the transition into the region’s ice age occurred swiftly.
Advanced seafloor drilling equipment and uncrewed underwater vehicles are also essential to Antarctic explorations. The German team drilled roughly 30 meters into the seafloor to retrieve the sediments that yielded their discovery.
Explore the World’s History Through Antarctica’s Rivers
The recent discoveries of ancient rivers under Antarctica offer exciting insights into Earth’s history. As intriguing as these findings are, they also serve as a stark reminder of how devastating extreme climate change can be. Sustainability must be at the forefront of individual and collective decisions moving forward for the planet’s sake.
Emily Newton is a passionate science who combines her love of writing and innovation with her expertise to deliver compelling content for science and tech enthusiasts. Emily Newton has been published in ReadWrite, Innovation & Technology, EuroScientist and more.
