Mass loss of the Antarctic Ice Sheet has been driven primarily by the thinning of the floating ice shelves that fringe the ice sheet1, reducing their buttressing potential and causing land ice to accelerate into the ocean2. Observations of ice-shelf thickness change by satellite altimetry stretch back only to 1992 (refs. 1,3–5) and previous information about thinning remains unquantified. However, extending the record of ice-shelf thickness change is possible by proxy, by measuring the change in area of the surface expression of pinning points—local bathymetric highs on which ice shelves are anchored6. Here we measure pinning-point change over three epochs spanning the periods 1973–1989, 1989–2000 and 2000−2022, and thus by proxy infer changes to ice-shelf thickness back to 1973–1989. We show that only small localized pockets of ice shelves were thinning between 1973 and 1989, located primarily in the Amundsen Sea Embayment and the Wil
New Antarctic observing system proposed
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Helicopter-based observations uncover warm ocean flows toward Totten Ice Shelf in Southeast Antarctica
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Abstract. Antarctic ice shelves provide buttressing support to the ice sheet, stabilising the flow of grounded ice and its contribution to global sea levels. Over the past 50 years, satellite observations have shown ice shelves collapse, thin, and retreat; however, there are few measurements of the Antarctic-wide change in ice shelf area. Here, we use MODIS (Moderate Resolution Imaging Spectroradiometer) satellite data to measure the change in ice shelf calving front position and area on 34 ice shelves in Antarctica from 2009 to 2019. Over the last decade, a reduction in the area on the Antarctic Peninsula (6693 km2) and West Antarctica (5563 km2) has been outweighed by area growth in East Antarctica (3532 km2) and the large Ross and Ronne–Filchner ice shelves (14 028 km2). The largest retreat was observed on the Larsen C Ice Shelf, where 5917 km2 of ice was lost during an individual calving event in 2017, and the largest area increase was observed on Ronne Ice Shelf in