On the tip of the Antarctic continent, a disaster is waiting to happen.
For the past few years, a crack has been forming in the Larsen Ice Shelf. Over the past few months this crack has been getting closer to the shore, and over the past week it jumped 11 miles. This means that an iceberg the size of Long Island could be days away from falling into the sea.
The crack in the Larsen shelf was first spotted in 2010, and took until 2016 to double in length. The growth of the crack has been accelerating during the last year, culminating in the 11 miles of growth over the past few days. The crack now lies a mere 8 miles from the sea. When the crack in the Larsen shelf finally reaches the shore, it will send a sheet of ice 2,300 square miles wide and 1,150 feet thick into the ocean.
Ice shelves break—or "calve"—all the time, so the crack in the Larsen shelf isn't something new. It is much larger than average, but the primary concern stems from the miles of ice behind it. Ice shelves are the floating fronts of much larger ice sheets or glaciers, and because these ice sheets are currently on land they have yet to effect sea level rise.
Increasing temperatures and climate change have turned otherwise stable ice sheets into ticking time bombs, and any ice shelf collapse can set them off. The few thousand square miles of floating ice about to break off the Larsen shelf are the only thing standing between the inland ice sheet and the warm ocean water, and when this chunk of ice breaks it could that ultimately raises sea levels by up to four inches.