For the first time scientists have been able to observe the power of an earthquake and tsunami to break off large icebergs a hemisphere away.
Kelly Brunt, a cryosphere specialist at Goddard Space Flight Center, Greenbelt, Md., and colleagues were able to link the calving of icebergs from the Sulzberger Ice Shelf in Antarctica following the Tohoku Tsunami, which originated with an earthquake off the coast of Japan in March 2011.
The finding marks the first direct observation of such a connection between tsunamis and icebergs.
When the Tohoku Tsunami was triggered in the Pacific Ocean on March 11 this spring, Brunt and colleagues immediately looked south.
Using multiple satellite images, Brunt, Emile Okal at Northwestern University and Douglas MacAyeal at University of Chicago, were able to observe new icebergs floating off to sea shortly after the sea swell of the tsunami reached Antarctica.
Nearly 50 square miles of ice broke off the Sulzberger Ice Shelf on the coast of Antarctica, resulting from waves generated by the Tohoku earthquake and tsunami.
“In the past we’ve had calving events where we’ve looked for the source. It’s a reverse scenario – we see a calving and we go looking for a source,” Brunt said.
“We knew right away this was one of the biggest events in recent history – we knew there would be enough swell. And this time we had a source,” he added.
The detail of the findings was published online in the Journal of Glaciology.