NASA scientists have photographed an enormous rift in the Larsen C ice shelf in Antarctica.
The crack is about 113 kilometers long, more than 90 meters across, and 0.5 kilometers deep.
Unchanged for 12 000 years until now
The rift is similar to a previous one that appeared on Larsen B, which caused the ice shelf to separate and disintegrate in 2002. Prior to that event, Larsen B had remained unchanged for almost 12 000 years.
What are ice shelves?
Ice shelves are the floating parts of glaciers in Antartica. They are not merely extensions into the ocean, but act as a crucial support for the polar ice cap. Most of the ice in Antarctica is not on water but on land, and without ice shelves, the continental ice will accelerate into the ocean and melt.
Operation Ice Bridge
The fracture was photographed on November 10 as part of Operation Ice Bridge, an airborne survey of Antarctic ice. The survey has been tracking the change in the South Pole due to the devastating effects of global warming.
To the surprise of scientists, satellite images revealed that the fissure had grown by about 13 miles over just a few months â€” much faster than its previous pace.
So what does this mean?
Eventually the rift could progress to the opposite edge of the floating tongue of ice and cause a massive iceberg to break off. While this is a natural process, there is concern that when it occurs, it could usher in a period of irrevocable retreat and possibly lead to the ice shelfâ€™s demise further contributing to the rise of global sea levels.
When will this happen?
It could happen in months, or it could take years, but monitoring the progression of this rift will help glaciologists better gauge the conditions on other ice shelves around the continent, which collectively hold back millions of cubic miles of ice.