Journey to the frozen frontier: mapping Lake Untersee

In October 2024, former Trimble intern Cole Schubert embarked on an expedition to one of the most remote and inhospitable places on Earth: Antarctica.

Thanks to an introduction by Daniel Butvidas at Trimble, Schubert became part of a research group headed by Dale Andersen from the SETI Institute. His mission: to map one of the largest freshwater lakes in Antarctica, Lake Untersee, using geospatial technology to study its unique ecosystem as an analog for extraterrestrial environments.

The expedition begins

Their journey began in Cape Town, South Africa, and on October 20, the team took a chartered flight to Novolazarevskaya Station, landing on the ice runway. After four days of organizing gear and preparing for the traverse, they snowmobiled five hours to Lake Untersee and set up camp.

Living conditions at the lake were challenging, with temperatures ranging from 15 to 20°F during the day to around 0°F at night. Propane heaters provided some warmth, but the cold and wind were relentless, with wind gusts up to 74 mph making it difficult to work.

The team saw several avalanches and heard them several times a week. The only other living creatures aside from the microbial structures in the lake were snow petrels and skuas flying in from the coast to nest. The constant daylight by the end of the trip added to the surreal experience.

The team started work at 9 AM, and worked until they were done for the day, as late as 7 PM, only stopping for extremely bad weather. They drank pure, unfiltered Antarctic glacial lake water and ate freeze-dried food, with occasional tortillas heated with ham and cheese. Endless hot chocolate and tea provided some comfort.

Mapping the lake inside and out

As the geospatial specialist, Schubert was responsible for all geospatial data collection and management. He used a variety of Trimble equipment, including two TSC7 data collectors, an R12i GNSS receiver, several bipods, three tripods, an SX10 total station, a Zephyr 3 base station, a TDL450h radio, R9 GNSS receivers and a DJI Mavic 3E. 

Each day, he set up the base station and radio transmitter to collect RTK positioning data throughout the lake region.

Tasks included mapping boulder fields, tracking lake levels and collecting RTK points of ice levels to understand how the ice elevation has changed over time. Schubert scanned the camp and the large boulder field at the southern basin from multiple angles, creating a highly detailed geospatial dataset for time series comparisons. 

His main objective was to scan an entire cirque at the southeast end of the lake (the first survey of this kind of the cirque in history), where a lake once existed but had since dried up. The old shorelines, or paleo-shorelines, were still visible, and Schubert conducted close to 25 scans at varying spatial resolutions to create a massive point cloud that clearly identified these shorelines.

Scientific discoveries

Lake Untersee, meaning "lower lake" in German, is a uniquely isolated freshwater lake in Antarctica. Covered by a thick ice sheet for hundreds (or even thousands) of years, it has a closed ecosystem with no atmospheric interaction. The lake’s water chemistry makes it a stand-in for the ocean moons of Europa and Enceladus of Jupiter and Saturn, respectively. 

The main life forms in the lake are bacterial mats that grow into conical stromatolites. Andersen and his team dived to collect and study these bacterial mats, while other PhD students collected ice, snow, water and air samples.

The microbial structures in the lake are of interest as they could reveal more about how life evolved on Earth and potentially on other planets. The unique conditions also provide insight into the past, offering clues about the early evolution of life and how it might survive in extreme environments. This research helps astrobiologists understand the potential for life on other celestial bodies.

By mapping the ancient lake and its surrounding environment, Schubert provided insights into how life could survive in similar harsh conditions on other planets or moons and a better understanding of the ecosystem and environmental changes like ice levels over time. 

The journey home

On December 9, the team began tearing down the camp and packing away all the gear. They snowmobiled back to Novolazarevskaya Station and, on December 14, flew back to Cape Town. The expedition provided valuable data and insights that will contribute to science’s understanding of life in extreme environments.

This expedition also marked the beginning of a new era of collaboration for the SETI Institute. “Dr. Tardy,” a recent addition to the SETI team, emphasized the importance of interdisciplinary research and the integration of advanced technologies in scientific exploration.

The equipment provided precise and reliable data, even in the harsh conditions of Antarctica. And the integration of UAV imagery with ground-based scans created a detailed and accurate representation of the lake and its surroundings. This data will enable scientists to conduct time series comparisons and study changes in the environment over time.