THE’Iceberg A23agreat over double in London, interrupted his Travel to drift started from Antarctica 39 years agocrashing on a submarine platform about 80 km from the coast of the South Georgia. This is the last press release of British Antarctic Surveey (BAS)the British research body specialized in monitoring the Antarctic continent, its glaciers and ecosystems. Despite the initial concerns for the local biodiversitycurrently the position of the iceberg is stable And it does not seem to hinder the supply routes of the island’s fauna, which houses seals, penguins and marine birds.
The long -term effects. With the progressive dissolutionA23a could fragment in smaller icebergsdangerous for navigation, and release into the ocean large quantities of nutrientswith consequences still to be evaluated on Ecosystem balances. The monitoring of A23A is also crucial to better understand the impact of Oceberg adrift. With the raising of the temperatures in Antarctica, the detachment of other gigantic blocks of ice could become more and more frequent, placing new challenges for both marine biodiversity and for the safety of commercial routes.
The impact of the A23a iceberg on the fauna of South Georgia
The approach of the A23a iceberg to the coasts of the South Georgia he turned on the alarm for the wildlife of the island, which hosts one of the most rich sea biodiversity of the planet, providing refuge to vast colonies of penguins (from the royal to the macaroni and gentoo), seals and marine elephants, as well as hosting Albatros and numerous marine birds that nest on its cliffs.
Scientists feared that the gigantic iceberg could block access to the main ones supply routes of the local fauna, as happened in 2004 in the sea of Ross, when theIceberg A38-B He had caused a drastic reduction in the number of local penguins and seals. Considering the imposing dimensions of A23A, in this case an impact was feared even more devastatingbut the block of the iceberg About 80 km from the coast it seems to have averted the worstavoiding the direct destruction of the habitats closest to the coasts, where animals usually feed.
The real impact on local ecosystems, however, can only be evaluated in the near future. Like all icebergs, the fate of A23a is of dissolvereleasing large quantities of nutrients in the ocean. This event could stimulate the growth of phytoplanktonat the base of the Marina food chain, increasing the availability of food for many species – including the penguins and seals that inhabit the island – which could benefit from the arrival of the ice giant. However, it is feared that a so drastic change In the composition of the waters it could favor some species instead of others, Descase the entire marine ecosystemwith effects still difficult to predict.
The consequences of the dissolution of A23A on navigation
The main danger, at the moment, concerns the navigation. Currently, the iceberg maintains its structure and it is so imposing that boats can easily avoid it. However, as happened with other icebergs in recent decades, theErosion of the sea and the increase in temperatures they will fragmente the ice walls progressively, giving rise to smaller blocks of ice and difficult to identify. These mini-oceberg they could represent one serious threat to navigation And fishing activities, making some maritime routes and local ports inaccessible to boats.
The journey of the Oyberg A23a from Antarctica to the South Georgia
The iceberg, a mountain of ice of about 3,200 km² (about twice the London surface), reached the coast of the South Georgia after a long journey that lasted 39 years.
It was in fact the 1986 when the large mass of ice (which then measured 3,900 km²) detached from the Filchner-Rronne glacial platform In Antarctica, starting to move the drift, that is, letting himself be transported by marine currents, directed north.
His journey was far from linear. Over 30 years it remained Stop in the seabed of the Weddell searesuming the drift only in 2020. Shortly thereafter, however, his journey north was slowed down again by one Taylor column, A circular oceanic current caused by the presence of underwater mountain ranges. Only at the end of the 2023the iceberg has resumed its movement, approaching South Georgia islands with a speed of 30 km per dayuntil you get stuck on an underwater platform a 80 km from the coast.
The causes of its detachment are still the subject of debate: while some scientists believe that it is a phenomenon naturallinked to the normal cycle of growth and fracture of the glacial platform, others hypothesize that the climate changetriggered by fossil fuels emissions, accelerated the process.
