May 20, 2024

Brunt Ice Shelf Breaks in Antarctica – Spawns Mega Iceberg 12x the Size of San Francisco

These images from the Copernicus Sentinel-2 satellite show the in the past and after of the huge piece of ice that broke away from the Brunt Ice Shelf. The image on the left shows fractures and gorges of the ice shelf on 25 October 2022, while the image on the right shows the iceberg breaking away from the ice shelf on January 24, 2023. The iceberg, determining 1550 sq km, separated from the 150 m-thick ice shelf a decade after scientists first spotted massive fractures in the rack. Utilizing radar images from the Copernicus Sentinel-1 objective, the animation shows the A81 iceberg breaking away from the Brunt Ice Shelf on January 25, 2023. Regular tracking from satellites provides unequaled views of events taking place in remote areas and show how ice shelves are actively responding to changes in ice dynamics, air and ocean temperature levels.

An iceberg around the size of Greater London broke off Antarcticas Brunt Ice Shelf due to a natural procedure called calving. The iceberg, measuring 1550 sq km, separated from the 150 m-thick ice rack a decade after researchers first spotted enormous fractures in the shelf. Credit: ESA– European Space Agency
The new iceberg is anticipated to be called A-81 with the smaller sized piece to the north likely determined as either A-81A or A-82. Icebergs are typically identified by an uppercase suggesting the Antarctic quadrant in which they were originally sighted, followed by a consecutive number, then, if the iceberg burglarize smaller sized pieces, a sequential letter suffix.
The split was initially reported by the British Antarctic Survey (BAS) as having actually happened on January 22 in between 19:00 and 20:00 UTC throughout a spring tide. BASs Halley VI Research Station, where glaciologists have been monitoring the habits of the ice rack, has actually remained unaffected by the calving event.
The research study station was relocated in 2017 to a more protected location after the ice shelf was considered unsafe. The station is currently around 20 km from the line of rupture and there are presently 21 staff dealing with the station to maintain power materials and centers that keep the scientific experiences running throughout winter.
This image, captured by the Copernicus Sentinel-2 objective on January 23, reveals the 1550 sq km iceberg breaking away from the Brunt Ice Shelf. The brand-new iceberg has actually been named/is anticipated to be called A81 with the smaller sized piece to the north most likely recognized as A81a. Credit: Contains modified Copernicus Sentinel data (2023 ), processed by ESA, CC BY-SA 3.0 IGO
ESAs Mark Drinkwater said, “After a number of years of iceberg calving watch, the long-awaited separation of the Brunt iceberg A-81 has actually finally occurred. The northward proliferation of Chasm 1 and timely choice for BAS to move the Halley Base to safer ground have actually been accompanied by what has been possibly the most longest-duration and in-depth examination of events causing natural calving from an Antarctic ice rack.
” Thanks to Copernicus, paired with in-situ and airborne measurements made by the British Antarctic Survey, the safety of the Halley Base has been protected. On the other hand, the mix of summer season images from Sentinel-2 and schedule of year-round and winter tracking by Sentinel-1 radar positioned the pattern of pressure and propagation of an ice rack fracture under the worldwide public microscopic lense.”
Dominic Hodgson, BAS glaciologist, included, “This calving occasion has actually been expected and becomes part of the natural behavior of the Brunt Ice Shelf. It is not connected to environment change. Our science and operational teams continue to keep an eye on the ice shelf in real-time to ensure it is safe, and to maintain the delivery of the science we carry out at Halley.”
Utilizing radar images from the Copernicus Sentinel-1 objective, the animation reveals the A81 iceberg breaking away from the Brunt Ice Shelf on January 25, 2023. The new berg is approximated to be around 1550 sq km, which is around the size of Greater London, and is around 150 m thick. It calved when the crack referred to as Chasm-1 split northwards severing the west part of the ice shelf. The white square indicated the last breakpoint near the McDonald Ice Rumples. Regular monitoring from satellites uses exceptional views of occasions taking place in remote areas. The Copernicus Sentinel-1 mission carries radar, which can return images regardless of day or night and this allows us year-round watching, which is particularly essential through the long, dark, austral cold weather.
Regular monitoring from satellites provides unequaled views of events occurring in remote regions and demonstrate how ice shelves are actively responding to changes in ice characteristics, air and ocean temperatures. In February 2021, another huge berg, around 1270 sq km (490 sq miles), broke off from the northern area of Brunt. Found by Sentinel-1 imagery, it has currently wandered away from the Brunt Ice Shelf into the Weddell Sea.
What happens now?
The calving of icebergs from an ice rack has actually been observed to be followed by change in the flow of ice into the ice shelf. It could influence the behavior of other fractures in the area if Brunt now experiences an acceleration.
Mark explained, “The calving of iceberg A74, and latest separation, now concentrates back onto the Halloween crack– whose extension might add to more destabilization of the Brunt Ice Shelf.
” A normal accompaniment to such stress release occasions and elimination of pinning of an ice shelf front by bottom functions such as McDonald Bank which forms the McDonald Ice Rumples might be an acceleration in the speed of ice streaming into the ice shelf. We will be using the capabilities of the Copernicus Sentinels to closely monitor the behavior and stability of the remaining Brunt Ice Shelf.”

These images from the Copernicus Sentinel-2 satellite reveal the before and after of the massive piece of ice that broke away from the Brunt Ice Shelf. The image left wing reveals fractures and gorges of the ice shelf on 25 October 2022, while the image on the right shows the iceberg breaking away from the ice shelf on January 24, 2023. Credit: Contains modified Copernicus Sentinel data (2022-23), processed by ESA, CC BY-SA 3.0 IGO
Satellite imagery verifies a massive iceberg, around five times the size of Malta, has actually finally calved from Antarcticas Brunt Ice Shelf. The new berg, approximated to be around 1550 sq km (600 sq miles) and around 150 m (500 feet) thick, calved when the fracture called Chasm-1 totally extended northwards severing the west part of the ice shelf. This enormous size makes it over 12 times the area of the city of San Francisco, California, which is 121 sq km (47 sq miles).
This crack was very first revealed to be extending in early 2012 after having been inactive for some decades. After numerous years of frantically sticking on, image information from the Copernicus Sentinel objectives aesthetically verify the calving event.
The timing of the calving event, although unexpected, had long been anticipated. Glaciologists have kept track of the numerous cracks and gorges that have actually formed in the thick Brunt Ice Shelf, which borders the Coats Land coast in the Weddell Sea sector of Antarctica, for years. It was only a matter of time that Chasm 1, which had been dormant for decades, would fulfill with the Halloween Crack, initially found on Halloween 2016.