• A massive ice blocknearly 100 times the area of Manhattan is poised to break off Antarctica’s Larsen C ice shelf, scientists reported. The fragile West Antarctic ice sheet — where Larsen C is located — holds enough frozen water to raise global oceans by at least four metres (13 feet).
• Recent studies have suggested that climate change may already have condemned large chunks of it to disintegration, though whether on a time scale of centuries or millennia is not known.
• The breaking off, or calving, of ice shelves is a natural process, but global warmingis thought to have accelerated the process.
• Warming ocean water erodes their underbelly, while rising air temperatures weaken them from above. The nearby Larsen A ice shelf collapsed in 1995, and Larsen B dramatically broke up seven years later.
• The ice block currently separating from Larsen C contains about 10 percent of its mass, and would be among the 10 largest break-offs ever recorded. 
• If all the ice held back by Larsen C entered the sea, it would lift global oceans by about 10 centimetres (four inches).
• “We are convinced — although others are not — that the remaining ice shelf will be less stable than the present one,” Oceans in recent decades have absorbed much of the excess heat generated by climate change, which has lifted average global air temperatures by one degree Celsius (1.8 degrees Fahrenheit).
• The world’s nations have undertaken in the Paris Agreement, inked in the French capital in December 2015, to cap global warming at “well under” two degrees Celsius (3.5 degrees Fahrenheit) above pre-industrial era levels.

About: Larsen C:

• The Larsen Ice Shelf is a long, fringing ice shelf in the northwest part of the Weddell Sea, extending along the east coast of the Antarctic Peninsula from Cape Longing to the area just southward of Hearst Island.
• It is named for Captain Carl Anton Larsen, the master of the Norwegian whaling vessel Jason, who sailed along the ice front as far as 68°10′ South during December 1893.
• In finer detail, the Larsen Ice Shelf is a series of shelves that occupy (or occupied) distinct embayments along the coast.
• From north to south, the segments are called Larsen A (the smallest), Larsen B, and Larsen C (the largest) by researchers who work in the area.
• Further south, Larsen D and the much smaller Larsen E, F and G are also named.