According to Radar images by ESA’s Sentinel-1 pair of satellites, an Antarctic iceberg A-74, which is twice the size of Mumbai, collided with its parent Brunt ice sheet and closely avoided breaking off of another piece from its parent. However, the collision has created a crack in the Brunt ice sheet making the other nose-shaped iceberg that is barely attached to its parent. The satellite images were shared by the space agency on August 20.
The official Twitter account of ESA’s Earth Observation wing posted the images on Twitter in the form of a GIF animation that shows A-74 colliding with the nose-shaped section of the Brunt ice sheet. A-74 had broken off the Brunt ice sheet in February this year. According to ESA Earth and Mission Science Division Head Mark Drinkwater, the nose-shaped iceberg is larger than A-74 and is still connected to the Brunt ice sheet despite the crack.
Berg-watch!The #A74 iceberg near collision with Brunt Ice Shelf as seen by @CopernicusEU #Sentinel1🚨In early August, strong winds have spun the iceberg around the western tip of Brunt.A-74 then gently 'booped' the ice shelf before heading southwards: https://t.co/JY8NeQjuwz pic.twitter.com/2qtqTMdPgW
— ESA EarthObservation (@ESA_EO) August 20, 2021
“If the berg had collided more violently with this piece, it could have accelerated the fracture of the remaining ice bridge, causing it to break away,” says Drinkwater in a statement. When the portion from where A-74 broke off was deemed unsafe because of propagation of a large crack, British Atlantic Survey had shifted its Halley VI Research Station to a more secure location.
Halley Research Station is a research facility in Antarctica operated by the British Atlantic Survey that studies Earth’s environment and observes the planet’s climate and space weather. The location of the station, despite being hardly accessible, is important because it is a climate-sensitive zone. Moreover, ice sheets are good indicators of climate not just because of their sensitivity to climate change but also because they play the main role in the global sea-level rise. The research station also keeps an eye on our planet’s atmosphere. For example, it was the Halley Research Station that discovered the hole in Earth’s ozone layer.
Scientists say that they are routinely monitoring the situation of the ice shelves using imagery from the Sentinel satellites. ESA’s Sentinel-1 constellation is a pair of satellites Sentinel 1A and Sentinel 1B, which were launched in 2014 and 2016 respectively. The satellites provide imagery of the earth’s surface in all weathers, day and night.