Study shows that an enormous iceberg three-and-a half times bigger than London once released astonishing 152 billion tonnes freshwater into the sea.
According to University of Leeds researchers, the massive slab of ice liberated fresh water as it passed the South Georgia island last year.
Satellite images have been used by experts to track A68A the “mega-iceberg”, also called A68A. It was discovered in Antarctica from the Larsen-C Ice Shelf.
The 152 billion tonnes of fresh water dumped into the ocean from it melting is enough to fill Loch Ness 20 times over, or 61 million Olympic sized swimming pools.
According to researchers, it melted in three months between 2020 and 2021.
A massive iceberg that once weighed three-and-a half times more than London released incredible freshwater into the sea, according to a study.
In July 2017, the iceberg broke away from Antarctic Peninsula. It traveled almost 2,500 miles through the Southern Ocean covering an area half the size of Wales.
The iceberg was six times the size of the previous record when it came off the shelf.
The news coverage was dominated by the Christmas 2020 incident, which occurred after it came within striking distance of South Georgia. This raised concerns about its potential damage to the fragile ecosystem.
British Antarctic Survey and Centre for Polar Observation and Modelling (CPOM), used satellite measurements for A68A iceberg area and thickness changes throughout its lifetime.
It had been melting enough, the authors discovered. This allowed it to drift away from South Georgia’s seafloor.
A side effect to melting is the massive amount of freshwater that gets dumped in the sea near the island.
British researchers described it as an invasive species that may have a profound impact on South Georgia’s marine habitat.
A68A was close to Antarctica for the first two-years of its existence, in the Weddell sea’s cold waters. It experienced very little melting during this time.
It began traveling northwards across Drake Passage, but it soon travelled through more warm water and started to melt.
Overall, the iceberg shrank by 219ft. This is a difference of its initial thickness, which was 67 meters, and its original thickness, which was 770ft. The rate of melting has increased sharply in the past.
Laura Gerrish (GIS and mapping specialist at BAS) and coauthor of this study, said that it was an interesting iceberg to follow, right from its creation until the end.
“Frequent measurements enabled us to track every movement and breakup of the Berg as it traveled slowly northwards through the Iceberg Alley, into the Scotia Sea and then picked up speed to approach the Island of South Georgia.
According to the team, if the keel of an iceberg is too thick, they can become stuck on the seafloor.
Scour marks could be harmful to the fauna. The iceberg can also prevent ocean currents from reaching predator foraging areas.
Three and a half years ago, the Antarctic Peninsula was broken up by the iceberg. The epic journey took the iceberg almost 2,500 mile across the Southern Ocean. This covered an area that is a quarter of the size Wales.
These potential consequences were all feared by A68A as it approached South Georgia. However, the latest study shows that A68A only briefly touched the seafloor.
The keel broke up shortly thereafter and, by the time the vessel reached the shallow waters of South Georgia, it was 462ft under the surface. This was enough for the vessel to escape the 492ft seabed.
According to the team, South Georgia’s ecosystem and wildlife will feel the effects of the massive iceberg’s arrival.
Icebergs can detach themselves from their ice shelves and drift along the currents and winds, releasing fresh meltwater as well as nutrients.
This affects local ocean circulation, and encourages biological production around the Iceberg.
The iceberg, at its maximum, was melting at 22 feet per month and releasing a remarkable 152 billion tonnes worth of water and nutrients.
British Antarctic Survey and Centre for Polar Observation and Modelling (CPOM), used satellite measurements for A68A iceberg area and thickness changes throughout its lifetime to map them.
Anne BraakmannFolgmann is the principal author of this study.
“Because A68A used a common route through the Drake Passage we hope to find out more about how icebergs take a similar trajectory and what their impact is on the polar waters’.
Tommaso Parrinello is the CryoSat mission manager at the European Space Agency. He said that satellite technology and techniques made it possible to follow every movement of an iceberg.
The images from satellites are used to determine the exact location and form of an iceberg. Data from satellites that measure the height of satellites can be added as well.
The findings have been published in the journal Remote Sensing of Environment.
What is the A-68 ICEBERG and what caused it to BREAK AWAY from ANTARCTICA
A huge crack in Antarctica’s Larsen C Ice Shelf caused a trillion-ton iceberg to rupture from the southern continent.
This huge chunk of ice is called iceberg A68 and measures approximately 5,800 km2 (2,240 miles). It’s four times larger than Greater London.
The fate of A-68 has been a mystery since its breakup. It’s not known what the massive mass will do next. Satellite tracking may be too difficult to follow and it might end up in shipping lanes.
The iceberg, which was the third largest in size ever measured by Antarctica’s Larsen C glacier, broke off from Antarctica’s southern continent. This detailed image was captured using instruments aboard Nasa’s Landsat 8 satellite.
Larsen C is still showing cracks according to experts. It’s possible for the ice shelf to collapse if these cracks continue growing.
Larsen C could collapse, and the remaining ice might increase global sea level by 4 in (10 cm).
Numerous scientists believe that the climate change did not cause the calving.
It could be that it simply reflects the natural decay and growth cycle of an ice shelf.