In the Arctic Ocean, some ice stays frozen year-round, lasting for many years before melting. But this winter, the region hit a record low for ice older than five years.
This, along with a near-record low for sea ice over all, supports predictions that by midcentury there will be no more ice in the Arctic Ocean in summer.
“First-year ice grows through winter and then to up to a maximum, which is usually around in March,” said Mark A. Tschudi, a research associate at the Colorado Center for Astrodynamics Research at the University of Colorado, Boulder. “As summer onsets, the ice starts to melt back.”
Some of the new ice melts each summer, but some of it lingers to grow thicker over the following winter, forming second-year ice. The next summer, some of that second-year ice survives, then grows even thicker and more resilient the next winter, creating what is known as multiyear ice. Some ice used to last more than a decade.
Back in 1984 approximately 25% of the Arctic’s ice was older than 5 years when March rolled around. Fast-forward to 2018 (only 34 years later), and less than 5% of the Arctic’s ice is older than 5 years come March. That’s an 80% drop in 35 years! Scary news, folks. Go see the Arctic before it’s gone forever…and wear a One World Bracelet on your trip and send us a pic!