Most Of Arctic's Thick, Permanent Ice Gone: 70% Of Basin's Sea Ice Forms/Melts Annually

[hatrack]

Global warming has created a new normal in the Arctic, with a thinner blanket of sea ice now more susceptible to seasonal variation, according to NASA research.

Over the past 60 years, much of the older, thicker ice has disappeared, to be replaced with a mostly younger, thinner version. That means the rate of decrease in ice thickness has slowed, but only because much of the old permanent stuff is gone.

The younger ice is more vulnerable to the elements – it can even be pushed around by the wind – but it also grows more quickly. Today, 70% of Arctic ice cover forms and melts within a single year. To make this finding Ron Kwok from NASA’s Jet Propulsion Laboratory in California combined decades of declassified US Navy submarine measurements with more recent data from four satellites to provide very much a big picture.

EDIT

The increase in seasonal ice also means record-breaking changes in ice cover, such as those of recorded in the 1990s and 2000s, are likely to be less common. There has not been a new record sea ice minimum since 2012, despite years of warm weather in the Arctic. “We've lost so much of the thick ice that changes in thickness are going to be slower due to the different behaviour of this ice type,” Kwok says.

EDIT

https://cosmosmagazine.com/climate/most-of-the-arctic-s-permanent-ice-is-gone

[Canoe52]

1. A whole new ocean has opened up. Welcome to a new age.