Ice that never fully returned
Arctic sea ice reached its lowest winter maximum on record this year, scientists said. The ice cover peaked smaller than in any winter since satellite records began. The finding adds to a year of extreme heat around the planet. Several regions recorded their hottest months ever measured this summer.
Winter is when Arctic ice should be at its thickest and widest. This year, it never came close to the historical average. Scientists said the missing ice is a direct result of warmer air and warmer water in the region.
Why the winter ice matters
Winter ice acts as a foundation for the ecosystem. When it is thin, it melts faster in the summer and leaves more open water. Open water absorbs more heat from the sun, which warms the region further. Scientists call this the ice-albedo feedback loop.
The shrinking ice threatens polar bears, seals, and the communities that depend on them. At the same time, shipping routes in the Arctic are opening earlier each year. More ships mean more noise, more pollution, and more risk of accidents in a fragile environment.
A warning for the rest of the world
The Arctic warms roughly four times faster than the global average. What happens there does not stay there. Melting ice sheets in Greenland are raising sea levels worldwide. Weaker polar winds are also letting cold air spill south in winter, which is why some regions see brutal cold snaps even as the planet warms.
Climate researchers said the record low is in line with what models predicted decades ago. They said cutting greenhouse gas emissions remains the only way to slow the decline. Each year of delay, they warned, locks in more ice loss for the generations that follow.