
LONDON – A team of scientists has calculated the area of floating ice that each of Antarctica’s ice shelves can lose before the portions connected to land collapse into the ocean, a study published in the journal Nature said.
The study indicates that although some ice plates can lose a large area without an immediate impact on the rest of the platform, other plates have a limited area where the melting of ice could have significant consequences for the whole, or they do not have any buffer zone.
The melting of Antarctic ice shelves has important consequences for global sea levels, scientists participating in the study conducted by the University of Erlangen-Nuremberg Institute of Geography and the Laboratoire de Glaciologie et Gophysique de l’Environnement in Grenoble, France, said.
The ice shelves’ floating plates, scientists said, anchor the area connected to land, preventing fractures, separation and the drifting of plate sections into the ocean.
Until now, researchers had not been able to accurately determine the support area required to prevent the collapse of ice shelves.
For each Antarctic ice shelf, researchers calculated and drew a map of the area with little or no effect at all, taking into account the stream of ascending ice whose loss has a low impact, something they called “passive shelf ice,” or PSI.
They found that, in general terms, roughly 13 percent of Antarctic ice shelves consist of PSI, with 7 percent in the Amundsen Sea and 5 percent in the Bellingshausen Sea, the most susceptible to ice loss.
The authors concluded that there was urgency in monitoring fractures in these platforms that goes beyond the margin where collapses could happen, since the Antarctic ice shelves have been shrinking over the past two decades.