Researchers from the **British Antarctic Survey (BAS)** have identified a direct correlation between **extreme ocean tides** and the **calving of giant icebergs** on the **Brunt ice shelf**, located in Antarctica.
The research, published in the journal **Nature Communications**, highlights the role of a crack known as **Chasm-1**, from which the **A-81 iceberg** originated in January 2023.
Since 2021, Brunt has lost three **gigantic blocks of ice**, one of them comparable in size to **Greater London**, which has intensified studies on the **internal and mechanical processes** preceding these events.
Synchronized calving of giant icebergs with tidal peaks: the case of iceberg A-81
Through a system of **continuous GPS monitoring** and **radar analysis**, the scientific team managed to track millimetric movements and **structural tension variations** of the ice shelf. The data reveal that **crack growth** and subsequent **rupture** systematically occur during **spring tides**, when gravitational forces reach their peak intensity.
This pattern was confirmed with the abrupt calving of **A-81**, whose surface reached **hundreds of square kilometers**. The event showed how fast and powerful the effect of tides can be on glacial systems.
Global impacts: how icebergs alter oceans, climates, and ecosystems
**Antarctic icebergs**, which account for about **50% of the continent’s annual ice loss**, not only reshape ice shelves but also alter **ocean circulation**, influence **water salinity**, and affect **marine ecosystems** where they pass through.
Understanding what regulates the **exact timing** of these calving events is essential for **assessing the long-term stability** of ice shelves and their influence on **sea level** and global climate dynamics.
Event prediction and new climate model
The BAS study suggests that, in addition to **internal ice conditions**, **external forces such as winds** and **tides** could be key elements in anticipating these events. This new perspective would allow the development of **short-term prediction models**, a tool that has been imprecise until now.
The study’s lead glaciologist, **Dr. Oliver Marsh**, highlighted:
“Recognizing how tides and winds impact the calving process brings us closer to being able to anticipate not only the occurrence but the **precise timing** of future ice calving events.”
