How to study Antarctic ice without blowing it up

The PistenBully 300 is a heavy-duty vehicle specifically designed to function in extreme polar conditions. It boasts wide tracks, immense pulling strength, robust cranes, and multi-purpose tools, making it an indispensable asset for any Antarctic base. Research conducted by Liu Guofeng at China University of Geosciences in Beijing indicates that the PistenBully may have an additional utility: conducting scientific research.

The Antarctic ice sheet, Earth's largest reservoir of freshwater, is currently shrinking. A transition zone, known as the firn layer, lies above the ice but below the surface snow. It is crucial to comprehend the thickness and behavior of this layer to accurately predict the ice sheet's long-term future and its impact on global sea levels.

However, visualizing the subsurface firn layer is a challenging task. Currently, geologists utilize an "active source" method, which involves dropping dynamite down a drill hole and listening to the resulting sound, processed through geophones, to construct a high-resolution image of the firn layer. This method, while effective, has its drawbacks.

It requires drilling holes, which may not always be feasible in polar conditions, and transporting and detonating explosives in sensitive environments. Liu Guofeng and his team sought an alternative sound source and discovered that PistenBullys could provide it. They tested their hypothesis in the Larsemann Hills of East Antarctica, where geophones were already installed.

By maneuvering the PistenBullys around the hills, they found that driving them along both sides of a line of geophones, parallel to the sensors, yielded the desired effect. Since the firn layer in the Larsemann Hills had been previously mapped using traditional methods, Liu could compare his newly acquired machine-generated images with the older ones.

To his satisfaction, the two sets of images were nearly identical. Liu's findings demonstrate a simpler and equally effective method for mapping the firn layer's structure without causing harm to the environment.