The Tohoku tsunami in March was strong enough to calve icebergs from the Sulzberger Ice Shelf in Antarctica, according to NASA.
NASA's Kelly Brunt, a cryosphere specialist at the Goddard Space Flight Center, and team were able to link the March tsunami off the coast of Japan with the birth of an iceberg.
The linkage was confirmed Using satellite images. Brunt, Emile Okal at Northwestern University and Douglas MacAyeal at University of Chicago saw new icebergs right after the sea swell from the tsunami reached Antarctica.
According to NASA the chain of events went like this:
- The earthquake off the coast of Japan set a tsunami in motion.
- Swells of water headed toward an ice shelf in Antarctica 8,000 miles away.
- After about 18 hours, these waves broke off chunks of ice about twice the size of Manhattan.
- These ice chunks haven't budged for 46 years before the tsunami.
- The swell was only about a foot high when it reached the ice shelf, but the waves were consistent and that led to the iceberg calving.
The linkage between waves and ice shelf breakage was a theory in the 1970s, but wasn't observed beyond models.
Brunt and team published the findings in the Journal of Glaciology.