The first evidence for massive and abrupt iceberg calving in Antarctica, dating back 19,000 to 9,000 years ago, has now been documented by an international team of geologists and climate scientists. Their findings are based on analysis of new, long deep sea sediment cores extracted from the region between the Falkland Islands and the Antarctic Peninsula. The study in the May 28, 2014 issue of Nature bears witness to an unstable Antarctic ice sheet that can abruptly reorganize Southern Hemisphere climate and cause rapid global sea level rise.
"One of the iceberg events in our data that is of particular interest took place 14,600 years ago and coincided with a huge ice-sheet melt, the famous Meltwater Pulse 1A, which according to previous studies led to a global sea level rise of about 4 meters within 100 years," says lead author of the study, Michael Weber at the University of Cologne in Germany.
"This is the first direct evidence that instabilities of the Antarctic ice sheet caused rapid sea level rise during the last glacial termination," says co-author Peter Clark, professor at Oregon State University.