Nature: Climate change is not only making Arctic sea ice disappear — it’s also changing the type of ice that forms. Researchers are now trying to determine how an increase in ‘pancake ice’ is affecting the far north, including whether it’s accelerating local warming. In the past, Arctic waters have been dominated by thick slabs of sea ice that last from one year to the next. But sea-ice cover is diminishing and thick ice that lasts for several years is disappearing fast, with researchers …