Why East Antarctica is a 'sleeping giant' of sea level rise

Are they really blaming melting glaciers on "heat waves" that reach -10c? Cause it almost sounds like they are trying to say the artic is melting due to freezing temperatures.

And how about the "experts" who describe weather events as impossible and inconceivable?

"At Dome C, the easterly apex of the sloping ice sheet, European researchers from the Concordia base staged a photo in swimwear under blow-up palm trees. The -10.1C (13.8F) temperature on March 18 was 38.5C (69.3F) higher than average, the biggest rise above normal observed by any weather station in history. Antarctica experts described the heat wave as "impossible", even "inconceivable".