World’s Largest Iceberg A23a Resumes Journey After Decades of Stagnation

The trillion-ton iceberg, twice the size of Greater London, is drifting northward and may impact ecosystems as it melts.

Iceberg A23a, the largest and oldest in the world, broke off from Antarctica in 1986 and remained grounded in the Weddell Sea for over 30 years.
Since 2020, A23a has been slowly moving northward, recently escaping a Taylor Column, a rotating ocean vortex that had trapped it for months.
The iceberg, covering approximately 4,000 square kilometers, is expected to drift toward South Georgia, where warmer waters will likely cause it to fragment and melt.
Researchers are studying the iceberg’s movement to understand its impact on marine ecosystems, including its role in nutrient distribution and carbon cycles.
A23a's melting process could provide nutrients to surrounding waters, fostering biodiversity, but its environmental effects remain uncertain.