Iceberg A-23A is looking a little blue these days. At the end of December 2025 NASA and NOAA's Terra satellite discovered massive iceberg covered with blue meltwater. A-23A is one of the largest and longest-lived icebergs ever discovered by scientists, but it risks being completely destroyed as it drifts in the warm waters of the South Atlantic.
In 1986, a flat-topped iceberg broke off from Filchner Ice Shelf in Antarctica. Then it was over 15,000 square miles– almost twice the size of Rhode Island. Today US National Ice Center estimates The iceberg's area is about 456 square miles. Although it is much smaller than its original size, it is still larger than New York City. IN July, August and September 2025 Iceberg A-23A suffered significant damage when it moved into the relatively warm summer conditions of the Southern Hemisphere by December.
MODIS (Moderate Resolution Imaging Spectroradiometer) on the Terra satellite took this photo of what was left on December 26, 2025. Astronaut on board a spaceship International Space Station Then (ISS) a photograph was taken a day later showing a larger view of the iceberg with an even larger pool of meltwater.
The extensive pools of “blue mush” on the iceberg's surface are likely the result of ongoing decay processes.
“The weight of the water sits inside the cracks in the ice and causes them to open,” he said. “Note also the thin white line around the outer edge of the iceberg, which appears to be held in blue meltwater—a ‘shaft-moat’ pattern caused by the upward bending of the iceberg plate as its edges melt at the waterline,” senior researcher at the University of Colorado Boulder. Ted Scambos explained in the statement.
The blue and white striped patterns are most likely related to stripes which were encased in ice hundreds of years ago as ice dragged along Antarctic bedrock.
“It's impressive that these bands are still showing up after so much time has passed, so much snow has fallen, and so much melting has occurred from below,” added the retired University of Maryland, Baltimore County scientist. Chris Shuman.
A sick iceberg could also leak. The white area to the left of it could be the result of what Schumann called a “blowout.” This occurs when the weight of water accumulating at the top of the iceberg creates enough pressure at the edges to break through it.
These signs indicate that the iceberg may only be a few days or weeks away from completely disintegrating.
“I certainly don’t expect the A-23A to last through the southern summer,” Schumann said.
The clearer the sky and warmer air and water temperatures in summer in the Southern Hemisphere are accelerating the process of disintegration in an area known among ice experts as the “graveyard” of icebergs. Climate change only speeds up this process as air and water temperatures continue to rise. break records.
Even as A-23A fades, huge new icebergs remain or drift along the Antarctic coastline. A-81, B22A and D15AEach of them has an area of more than 500 square miles and can also begin its journey north.
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