Despite setback, researchers uncover new findings at Antarctica’s Thwaites Glacier

Thwaites Glacier Research Expedition: A Detailed Report

Key Concepts:

• Thwaites Glacier: A massive glacier in West Antarctica, often referred to as the “Doomsday Glacier” due to its potential for significant sea level rise.
• Firn: Snow that is transitioning to ice, representing a record of past climate conditions.
• Radargrams: Two-dimensional images created using radar to map the terrain beneath the ice.
• Subglacial Discharge: Water released from under the glacier, often warmer and contributing to melting.
• Moorings: Underwater instruments deployed for long-term data collection.
• RIFT-OX: A device used to access and sample water from deep within glacial rifts.
• KOPRI: Korea Polar Research Institute, the organization owning the icebreaker Araon used for the expedition.

I. Drilling Project Setback & Alternative Data Collection

The report begins with a setback in a primary research goal: successfully drilling through the Thwaites Glacier to install a long-term ocean monitoring station. The drilling attempt, led by New York University glaciologist David Holland, failed to reach the ocean beneath the ice. Holland described the outcome as “nothing, absolutely nothing, a little bit Shakespearian.” Despite this failure, the team adapted, focusing on deploying a distributed temperature sensor down the partially drilled hole, acknowledging it was “better than nothing.” Miles O’Brien, the reporter, humorously participated in the setup despite his arm amputation, highlighting the team’s collaborative spirit.

II. Aerial Radar Surveys & Glacier Mapping

The core of the month-long scientific campaign, launched from the Korean icebreaker Araon, involved extensive aerial surveys using powerful radar technology. Led by Montana State University glaciologist Chris Pierce, the team flew over 1,800 miles of the glacier, utilizing radar to map the terrain beneath the ice. This radar operates by sending radio waves downwards and analyzing the returning echoes to create “radargrams” – essentially MRI-like images of the ice and bedrock. Pierce emphasized the “really good-quality data and coverage” obtained, crucial for understanding the glacier’s stability. The data helps identify areas where the glacier rests on a low-friction surface, making it more susceptible to rapid retreat. Pierce stated, “Once you get past a certain point, you're going to have a really, like, low-friction surface on which the glacier can slide.”

III. Firn Core Analysis & Sea Ice Monitoring

Complementing the radar surveys, sea ice scientist Siobhan Johnson of the British Antarctic Survey conducted firn core sampling. Firn cores, representing approximately six months of accumulated snow, provide a historical record of temperature fluctuations. Johnson demonstrated how clear ice layers indicate warmer periods and identified “melt layers” within the core. She also monitors sea ice density, noting a sharp decline since 2016 linked to climate change and altered wind/ocean currents. While melting sea ice doesn’t directly contribute to sea level rise, its loss can accelerate the melting of land ice like Thwaites by allowing warmer ocean water to reach the glacier’s underside. Johnson explained, “The cover of the sea ice in this area is quite important for ocean heat transport, which will melt the underside of the Thwaites.”

IV. Underwater Data Collection & the Role of Subglacial Discharge

The expedition also involved deploying and recovering underwater moorings to collect long-term data on ocean salinity, temperature, currents, and chemical composition. An autonomous underwater glider was also used for profiling. A particularly innovative approach involved the RIFT-OX device, developed by Jamin Greenbaum of the Scripps Institution of Oceanography. This device, deployed from a helicopter into glacial rifts, allows scientists to access and sample water at depths up to 2,800 feet.

Greenbaum’s research focuses on identifying “subglacial discharge” – water originating from beneath the glacier due to geothermal heat and friction. He hypothesizes that this discharge acts as “lighter fluid” accelerating the melting process when it mixes with warmer ocean water. His early data confirmed the presence of subglacial discharge in a specific area, supporting this hypothesis. Greenbaum stated, “You know, I like to think of the warm ocean as like the fire. And this subglacial discharge, I like to think of it like lighter fluid that's getting sprayed into the fire, and it just -- it just blows the whole thing up.”

V. Collaboration & Future Research

The research campaign is a collaborative effort between KOPRI, the University of Texas, and Montana State University. KOPRI plans to return in two years to continue the research. The report concludes by emphasizing the urgency of the situation, noting that the Thwaites Glacier is moving faster than the pace of scientific understanding.

Conclusion:

The expedition to the Thwaites Glacier, despite facing initial setbacks, yielded valuable data through a combination of aerial radar surveys, firn core analysis, underwater monitoring, and innovative techniques like the RIFT-OX deployment. The research highlights the complex interplay between sea ice, ocean currents, subglacial discharge, and the glacier’s underlying terrain, all contributing to its accelerating melt rate. The findings underscore the critical need for continued research to accurately predict the glacier’s future behavior and its potential impact on global sea levels.