File:Iceberg A-23A Continues Northward Drift (MODIS 2023-12-24).jpg

English: On December 20, 2023, clear skies allowed the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite to capture a true-color image of the world’s largest iceberg drifting north-eastward into the South Atlantic Ocean.

Iceberg A-23A calved from the Filchner Ice Shelf in 1986 but did not drift far before it became stuck on the seafloor of the southern Weddel Sea. It remained nearly motionless until 2020, when scientists first spotted tiny movements. However, it wasn’t until late in 2023, during the Southern Hemisphere springtime, that the massive ‘berg began to make serious headway in its drifting travels. By early December, A-23A had passed the tip of the Antarctic Peninsula and was heading towards warmer waters.

Despite the long hours of daylight and the relatively warm air temperatures typical of late spring/early summer in the Antarctic, A-23A does not appear to be losing much mass. As of November 24, 2023, the iceberg measured about 4,300 square kilometers (1,700 square miles), according to the U.S. National Ice Center. This is essentially the same size estimated on the December 21, 2023, update. This means that A-23A remains the largest of any iceberg currently adrift in the world’s oceans. Larger bergs have come and gone. For example, icebergs A-68 and A-76 briefly took the largest iceberg title in 2017 and 2021, respectively, before they fractured into smaller ‘bergs.