A huge iceberg called the A68 releases more than 1.5 billion tons of fresh, freshwater into the ocean every day due to melting ice. This is 150 times the amount of water consumed daily by the UK. The A68 was briefly the largest iceberg in the world. Its area was almost 6,000 square kilometers when it separated from Antarctica in 2017. But by early 2021 it was gone, as were billions of tons of ice.
The team from the University of Leeds analyzed the satellite data to gain insight into the icy shoreline as it traveled north across the Southern Ocean and into South Antarctica.
The researchers estimated the variations in the melting of the coast that has existed for three and a half years. One of the key periods is when the A68 was approaching warmer climates in South Georgia. There was concern that the huge ice block could be stranded in the surrounding shallow water and block the path of millions of penguins, seals and whales, but that did not happen. The researchers found that the A68 had lost enough of its thickness to be able to continue sailing.
By April last year, the A68 had broken down into much smaller parts that could no longer be tracked. But the impact on the ecosystem will be permanent. These smaller parts have a significant impact wherever they occur, and their freshwater will change local currents. Iron, other minerals, and organic matter that they have accumulated over the course of their lives will end up in the oceans and alter their biological reproduction.
The British have set up devices near the A68 coast designed to monitor conditions, and the data collected is interesting. There are strong indications of a change in the flora of phytoplankton around the A68 coast, as well as in the deposition of materials in the deeper parts of the ocean, the researchers conclude.