Huge Iceberg Could Threaten Penguins in the South Atlantic Ocean
Scientists are worried that a large iceberg heading toward an island in the South Atlantic Ocean could threaten wildlife there.
Researchers say the iceberg is the largest in the world. It is moving through the South Atlantic toward the island of South Georgia. The island is a British overseas territory that is about 1,400 kilometers east of the Falkland Islands.
Scientists say South Georgia is a main mating ground for wildlife, especially penguins and seals.
The iceberg is officially known as A23a and it measures about 3,500 square kilometers. It has existed since 1986, when it broke off from the Antarctic shelf.
Andrew Meijers is an oceanographer with the British Antarctic Survey. He told the French News Agency (AFP) that scientists have been using satellite imagery to follow the iceberg's movements.
Meijers said observations had shown the iceberg had not broken into smaller pieces like some other so-called "megabergs" that passed through the Southern Ocean. He added that predicting the iceberg's exact path is difficult. But ocean conditions suggest it should reach South Georgia in two to four weeks.
Meijers said he is worried the iceberg will get caught on the underground continental shelf around South Georgia. But he said it is also possible the large ice mass could miss the shelf and continue moving into open waters beyond South Georgia.
If the iceberg does get caught, or stuck, on the shelf, Meijers said it could remain there for months or it could break into pieces. Meijers is concerned that this could harm efforts by penguins and seals on the island to feed and raise their young. Icebergs that have grounded there in the past led to the deaths of young penguins and seals, he said.
Raul Cordero is a mechanical engineer from Chile's University of Santiago. He is also a member of the National Antarctic Research Committee. Cordero told AFP he thinks the iceberg will miss South Georgia.
"The island acts as an obstacle for ocean currents and therefore usually diverts the water long before it reaches the island," he said. "The iceberg is moved by that water flow, so the chances of it hitting are not that high." Cordero added, however, that some iceberg pieces could affect the island.
Soledad Tiranti is a glacier expert who is currently on an Argentinian exploration trip in the Antarctic. She told AFP that icebergs such as A23a "are so deep that before reaching an island or mainland they generally get stuck" on the seabed.
It is currently summer in South Georgia and penguins and seals from the area have been looking for food in the cold Antarctic waters to bring back to their young. Meijers said the animals might have to go around the iceberg if it gets stuck.
He added that if they had to move around it, this would take a lot of their energy, possibly leading to animal deaths. The seal and penguin populations on South Georgia have already been having a "bad season" with cases of bird flu, Meijers said.
Iceberg A23a remained stuck for 30 years before finally breaking free from the Antarctic shelf in 2020. Scientists watching its movements say the iceberg has followed nearly the same path as other large ice masses in the past.
The icebergs generally pass the east side of the Antarctic Peninsula through the Weddell Sea along a path known as "iceberg alley." They are pushed by the world's most powerful ocean current system, the Antarctic Circumpolar Current.
I'm Bryan Lynn.
Agence France-Presse reported on this story. Bryan Lynn adapted the report for VOA Learning English.
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Words in This Story
iceberg – n. a huge piece of ice that floats freely in the sea
shelf – n. an area of relatively shallow water that surrounds a land mass
continental shelf –n. an area of relatively shallow water that extends from the world's great land masses and beyond which is the deep ocean
obstacle – n. something that makes it difficult or gets in the way of doing something; a barrier
divert – v. to send someone or something to a place other than where they had expected to go
glacier – n. a large mass of ice that moves very slowly, usually down a hill or valley
alley – n. a narrow street or place where things are likely to pass
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