Six narwhals equipped with sensors collected temperature, salinity, and depth data in Scoresby Sound, Greenland, reaching areas almost inaccessible to ships. The measurements revealed traces of Atlantic water about 300 kilometers from the coast and showed relatively warm water reaching deep basins in front of glaciers.
Six narwhals (Monodon monoceros) equipped with sensors allowed scientists to gather oceanographic information in remote areas of Scoresby Sound, on Greenland’s east coast. While the animals conducted their usual movements, the equipment recorded temperature, salinity, and depth at points that scientific vessels rarely, if ever, manage to reach.
According to a report from Revista Galileu, published on August 28, 2026, by Arthur Almeida, the results are part of a study published on August 26 in the journal Science Advances. The research revealed traces of Atlantic water about 300 kilometers offshore and showed that this relatively warm water reaches deep areas close to glaciers.
Scoresby Sound is the largest fjord system in the world
Scoresby Sound is the largest fjord system on the planet, but sea ice, vast distances, and access difficulties limit the number of measurements taken by research vessels.
Narwhals Entered Areas Where Vessels Almost Never Go
The narwhals managed to collect data in areas that research vessels rarely or never reach due to sea ice and accessibility challenges — Photo: Wikimedia Commons
The animals’ natural ability to navigate cold, remote waters allowed access to sparsely documented locations.
Mads Peter Heide-Jørgensen, a professor at Greenland’s Institute of Natural Resources and the study’s lead researcher, noted that the narwhals traversed parts of the fjords where there are very few prior measurements.
Sensors Recorded Temperature, Salinity, and Depth
A CTD sensor attached to a narwhal — Photo: Mads Peter Heide-Jørgensen
The equipment transformed each animal into a mobile data collection platform.
During the natural movements of the narwhals, the sensors recorded temperature, salinity, and water depth, producing measurements in locations that could require difficult or costly operations if investigated solely by vessels.
Atlantic water appeared about 300 kilometers from the coast
One of the discoveries occurred far beyond the regions typically reached by surveys.
Heide-Jørgensen stated that the researchers found traces of Atlantic water approximately 300 kilometers from the coast, something that, according to him, had not been demonstrated in that area in this way before.
Fjord combines cold polar water and warmer Atlantic water
Scoresby Sound contains different bodies of water with distinct characteristics.
Polar Water is cold and originates from the Arctic. In contrast, Atlantic Intermediate Water is relatively warmer and saltier, arriving in the region from the Atlantic Ocean.
This combination makes measurements of temperature, salinity, and depth particularly important for understanding how the system functions.
Animal data broadened the information used in models
Susanne Ditlevsen, a professor at the University of Copenhagen and co-author of the research, emphasized that the new observations filled areas previously underrepresented in surveys.
According to her, the availability of measurements from these locations allows them to be incorporated into models, creating a more comprehensive view of ocean conditions.
A field team tagging a narwhal — Photo: Carsten Egevang
The analysis was not based solely on the records produced by the six narwhals.
The researchers combined the new measurements with historical oceanographic information from the WOD, the World Ocean Database.
From the two sets of data, the team developed a model relating temperature, salinity, and depth.
Layer of Atlantic water became thicker
The results indicated a change in the composition of the waters present in the fjord system.
The layer corresponding to Atlantic water has become thicker, while the upper layer formed by polar water has shown a reduction in thickness.
These differences have helped researchers track how the water masses are distributed in the depths of Scoresby Sound.
Relatively warm water reaches deep basins in front of the glaciers
The team identified that Atlantic water can penetrate deeply into the fjords.
This relatively warm water mass reaches deep basins located in front of the glaciers, even in areas situated hundreds of kilometers inward in the system.
The discovery establishes a pathway through which warmer waters can reach near the ice.
Researcher associates warm water with glacier melting
Heide-Jørgensen stated that this is the water that helps melt the glaciers.
According to the researcher, the results show how the inflow of relatively warm water has contributed to accelerating the ice loss process in the region’s glaciers.
The conclusion is linked to the conditions observed and modeled from the data collected in the fjord.
Melting releases large volumes of freshwater into the ocean
The studied consequences extend beyond the limits of Scoresby Sound.
The melting of glaciers and the Greenland ice sheet releases large volumes of freshwater into the ocean, a change that can affect ocean circulation.
Changes in this circulation can, in turn, influence climate patterns far beyond the Arctic.
New measurements can improve climate models
Researchers consider the data important for studies on climate change as well.
Ditlevsen explained that the melting of glaciers plays a crucial role in the large climate models used to project future changes.
According to her, improving the understanding of this process is especially important because Greenland holds a vast amount of ice.
Six narwhals expand observations in a little-studied region
The use of six narwhals enabled measurements in sections of Scoresby Sound that remained difficult to reach by conventional methods.
The data showed the presence of Atlantic water about 300 kilometers from the coast, indicated changes in the thickness of water masses, and revealed that relatively warm waters can reach deep basins near the glaciers, providing new information for oceanographic and climate research.
In your opinion, what stands out most in this research: using narwhals as data collectors, reaching regions practically inaccessible to ships, or identifying relatively warm Atlantic water making it so close to the glaciers? Share your thoughts in the comments.