{
  "id": 9592407,
  "title": "Greenland ice shelf weakened by estuary ahead of recent calving event",
  "url": "https://urgent.news/2026/09/24/greenland-ice-shelf-weakened-by-estuary-ahead-of-recent-calving-event",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-24T17:20:08.000Z",
  "source": {
    "name": "Phys.org",
    "slug": "phys-org",
    "url": "https://phys.org/news/2026-09-greenland-ice-shelf-weakened-estuary.html"
  },
  "original_language": "en",
  "account": "In August 2026, a massive iceberg roughly the size of Manhattan calved from Greenland's Petermann Ice Shelf, marking the glacier's largest calving event since 2020. Scientists from the Cooperative Institute for Research in Environmental Sciences (CIRES) have now uncovered a new factor that may have contributed to this event: the formation of an ice shelf estuary. This estuary, where salty ocean water and freshwater from meltwater rivers mix, was discovered in 2021 and led to new research published in The Cryosphere. The study, led by CU Boulder geography and CIRES doctoral student Michela Savignano, reveals how the estuary formed and weakened the ice shelf by allowing ocean water to enter and flow back into it. This process of forming and reforming over multiple melt seasons may have weakened the ice shelf through the loading and unloading of ocean water, potentially contributing to the calving event. The research suggests that estuaries, while previously believed to be beneficial, can also be harmful to ice shelves. Understanding these estuaries is crucial as polar regions continue to warm, with implications for future calving events and sea level rise.",
  "summary": "In August 2026, an iceberg the size of Manhattan broke away from the Petermann Ice Shelf in northern Greenland. It was the glacier's largest calving event since 2020. Long before the breakup, CIRES scientists were developing a new method to understand the planet's first known ice shelf estuary on the Petermann Ice Shelf.",
  "key_points": [
    "Massive iceberg, Manhattan-sized, calved from Petermann Ice Shelf in August 2026",
    "Ice shelf estuary, formed in 2021, allowed ocean water to enter and weaken shelf",
    "Estuary, previously thought beneficial, can also harm ice shelves, crucial for future calving events"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}