Cutting through ice for climate change mystery

A Sino-Russian scientific research team has conducted borehole camera operations to get a complete temperature profile of the interior of a 545-meter-thick glacier that they drilled into during China's earlier 40th Antarctic expedition, from Nov 2023 to April 2024.

Now, in the 41st expedition, which began last November and will be on till May, China has acquired key parameters such as borehole temperature, inclination, and changes in borehole diameter, using a new type of independently developed technology to study the drilled hole.

The importance of these results for research in climate change cannot be overestimated. The Antarctic ice sheet, which can trigger a global sea level rise of 70 meters should it melt, is the largest potential factor affecting future sea level changes. However, there is considerable uncertainty regarding how exactly the melting Antarctic ice sheet contributes to sea level changes, because of our insufficient understanding of the evolution of the ice sheet in the past.

The East Antarctic Ice Sheet accounts for a high percentage of the world's ice and can significantly impact global climate change. Its internal ice layers, like pages of a history book, record information about past climate changes. By analyzing its core, scientists can understand changes in temperatures in the past, precipitation, atmospheric composition, and other climatic factors, thereby constructing climate evolution models and, more importantly, comprehending future climate change trends.

In the 2000s, the Chinese team conducted studies to note fluctuations on the surface of the interior ice sheet at Grove Mountains since the Pliocene Epoch. The Larsemann Hills region surveyed by the Sino-Russian joint team abuts the Princess Elizabeth Land ice sheet, and understanding its subglacial geological environment is crucial to understanding the dynamic evolution mechanisms and mass balance characteristics of the Princess Elizabeth Land terminal ice sheet, representing an important step in uncovering the evolutionary laws of the East Antarctic Ice Sheet.

The research team also recovered about 7 cubic meters of drilling fluid from the hole. If someday mankind learns enough about the laws governing climate change to be able to curb it, the contribution of Chinese teams should not be forgotten.