One of the Biggest Icebergs in History is loose, but the real question is what happens next
Breaking away from the Larsen C Ice Shelf on Antarctica, one of the biggest icebergs in recorded history is roughly the size of Delaware.
For years now, scientists have watched with a mixture of horror and fascination as a crack emerged on the Larsen C Ice Shelf on the continent of Antarctica. It’s not uncommon for ice shelves to crack and break into icebergs, but this one is larger than most. In fact, it is now the largest recorded iceberg in history.
The now independent block of ice and snow, known as A68, is one trillion tons and measures 5,800 square kilometers. The region is just south of the Drake Passage, the body of water between South America and Antarctica. There is a sizeable peninsula between the Larsen C ice shelf and the open water, however.
While the crack separates the iceberg from Antarctica, A68 has been floating for years now, so thankfully its release from the continent won’t affect sea levels.
While its separation from Antarctica has been expected for months, even years, the actual split occurred sometime between July 10 and July 12, 2017. At the moment, the fledgling iceberg is pretty much exactly where it was, but as currents push the now unattached chunk of ice, it should eventually begin to drift away.
After that, it’s anyone’s guess what happens.
The crack was first recorded by satellite images taken in the 80s, but it has accelerated over the last few years. The reason for the break isn’t clear either, and it is too early to claim that climate change played a part, at least not directly. The nearby Larsen A and Larsen B ice shelves both suffered collapses of their own in 1995 and 2002, respectively, and that was due in large part to an increase in water temperature. The ice on the Larsen C Ice Shelf, however, has actually thickened recently, but the collapse of Larsen A and B resulted in the dramatic acceleration of the glaciers. That, in turn, created an imbalance that may have led to the creation of A68.
But while climate change may not have directly led to the ice shelf coming free, it might have a huge impact on what happens next. The majority of A68 ill probably remain exactly where it is now for a little while at least, but the part of it furthest from the remaining continent may crack into smaller icebergs that would then move north into warmer waters. If, or when that happens, when those smaller icebergs melt it will contribute to rising sea levels, especially in coastal areas of South America that are already vulnerable to rising water levels.
“If Larsen C now starts to retreat significantly and eventually collapses, then we will see another contribution to sea level rise,” David Vaughan, glaciologist and director of science at British Antarctic Survey told Reuters
The creation of the iceberg A68 may be the news that is grabbing all the headlines today, but the real story is what happens next.