Scientists “Genuinely Shocked” at Antarctic Sea Ice Drop

New York Times:

It’s winter in the Southern Hemisphere, when ice typically forms around Antarctica. But this year, that growth has been stunted, hitting a record low by a wide margin.

The sharp drop in sea ice is alarming scientists and raising concerns about its vital role in regulating ocean and air temperatures, circulating ocean water and maintaining an ecosystem crucial for everything from microscopic plankton to the continent’s iconic penguins.

“This year is really different,” said Ted Scambos, a senior research scientist at the University of Colorado Boulder and an Antarctica expert at the National Snow and Ice Data Center. “It’s a very sudden change.”

A continued decline in Antarctic sea ice would have global consequences by exposing more of the continent’s ice sheet to the open ocean, allowing it to melt and break off more easily, contributing to rising sea levels that affect coastal populations around the world.

Less ice also means less protection from solar rays, which can raise the water temperature, making it harder for ice to form.

At the end of June, ice covered 4.5 million square miles, or 11.7 million square kilometers, of ocean around the continent, according to NSIDC data. That’s nearly a million square miles less than the expected average from approximately 40 years of satellite observations.

The clear departure from previous years is startling, since sea ice around Antarctica has been slower to respond to climate change than ice in the Arctic Ocean.