Context:

Researchers corrected a long-standing map error by identifying an unidentified Antarctic feature as an island in the northwestern Weddell Sea, after which they mapped and surveyed it for the first time. The discovery stemmed from an expedition aboard the AWI icebreaker Polarstern when harsh weather forced shelter on Joinville Island, revealing a rock-like formation previously labeled as a danger zone. The team used echo sounding and drones to chart the seabed, revealing an island about 426 feet long that rises roughly 52 feet above water. The finding underscores gaps in nautical charts, prompting a formal naming proposal to SCAR and signaling that much of the Weddell Sea remains uncharted. This work hints at further landforms awaiting discovery as charting coverage remains incomplete.

Dive Deeper:

• An Antarctic feature long marked as a navigation hazard was identified as an actual island during an AWI expedition in the Weddell Sea. The discovery occurred after researchers sheltered on Joinville Island due to severe weather and then observed a rock-like ‘iceberg’ that proved to be land.

• The team conducted circumnavigation and seabed surveying using an echo sounder and drone imaging, marking the first time the region has been formally recorded as an island. The feature was not previously named and will enter the formal naming process with a proposal to SCAR.

• Measured dimensions place the island at roughly 426 feet in length and 164 feet in width, with an emergence of about 16 meters (52 feet) above water. Officials note it resembles nearby icebergs from an aerial view, complicating initial identification.

• A contributing factor to the mislabeling is the prevalence of uncharted shoals and hummocky underwater mounds, where depths can change abruptly over short distances. Most nearshore areas rely on low-resolution satellite data, creating white spots or gaps in nautical charts.

• The finding highlights that less than a quarter of the Weddell Sea is fully charted, suggesting many coastal and seabed features remain undiscovered. Officials emphasize ongoing potential for new landforms to be identified as mapping coverage improves.