When a trillion ton iceberg snapped off the Antarctic Peninsula’s Larsen C ice shelf in July, the entire world spent a few days geeking out over stunning satellite imagery of Earth’s frozen continent. But those who’ve stuck with the Delaware-sized iceberg, now called A68, on its slow journey into the Weddell Sea, know that the images are only getting better.
A68's first baby photos were captured in the darkness of polar night, but as spring arrives and daylight returns to Antarctica, scientists are getting their first sunlit glimpses of the ‘berg, which is techincally one main berg (A68a, the one that looks eerily like Manhattan), a smaller chunk to the northeast (A68b, think Randalls Island), and a bunch of even smaller, unnamed fragments.
On September 11th, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra Satellite captured this stunning view of A68, which has separated considerably from the Larsen C ice shelf, creating a gap that’s being filled in by extremely thin “frazil” ice:
On September 16th, NASA’s Landsat 8 satellite captured the visible (left) and thermal (right) images below. These images also accentuate the rift between the ‘berg and the shelf, as well as a growing layer of frazil ice and a smattering of thicker, “melange” ice that hugs closer to A68's western shoreline:
According to Christopher Shuman, a cryospheric scientist working for the University of Maryland system at NASA’s Goddard Spaceflight Center, a period of strong offshore wind action beginning in early September has helped to clear away sea ice surrounding the new icebergs, and rotate A68 out to sea at its southern end. “The rift there is now on the order of 20 km...and there was plenty of thin sea ice and or even open water in what was the rift as of 16 September,” Shuman told Earther via email.
He added that A68b is now clearly headed for the Bawden Ice Rise, a key stabilization juncture for the remaining Larsen C shelf.
Scientists plan to continue monitoring A68, and the now slimmed-down Larsen C ice shelf, in the months and years to come—their fate has become an enormous scientific experiment. Key questions researchers are now trying to answer include whether the calving event on July 12th will lead to further destabilization and retreat of the Larsen C ice shelf, and how we can incorporate the physics of this event into models to better predict the fate of glaciers threatened by human-caused climate change. Scientists also plan to study the seabed exposed by Larsen C, which was recently designated a protected area.
And, of course, they’ll continue to take jaw-dropping photos.