A massive portion of the Larsen C Ice Shelf is calving at increased speed with scientists revealing that an iceberg the size of Delaware could break off from Antarctica very soon.
According to researchers with British Project MIDAS, the outer end of the calving iceberg started accelerating at fastest speeds ever recorded. While scientists are convinced that calving will happen, they are not in a position to reveal when it will happen.
“We still can’t tell when calving will occur – it could be hours, days or weeks – but this is a notable departure from previous observations”, said scientists with Project MIDAS.
At the end of May, the crack didn’t have a long way to go – only about eight miles – before the iceberg would break free. But the crack didn’t lengthen over the course of last month and this means that the ice is still attached. but the calving has suddenly started to move far faster than it ever has: more than 30 feet per day suggesting that the break off is imminent and could happen soon.
When the iceberg breaks off, it will reduce the size of Larsen C Ice Shelf by 10 per cent. The 2,000-square-mile iceberg would then become the third largest in recorded history.
Scientists have warned that the break off could set into motion a destabilization sequence and could destabilize the entire 19,300-square-mile shelf and eventually cause it to disintegrate. This happened with the Larsen B ice shelf after a similar iceberg calved from there in 2002.
The Sentinel-1 satellite image data below illustrates the substantial change in ice speed from early June to late June.
The Project MIDAS team said on June 24 that the rift has been widening about 6 feet per day since the end of May, but there has been no observable change in the length of the crack since then.
When the iceberg does break free and sail into the Southern Ocean, it should not contribute to sea level rise, since it’s already on the water. But if the full Larsen C ice shelf collapses, the land-based glaciers that it is holding back could have a significant impact on sea level.