The amount of Arctic ice at its annual high point – the “maximum” – was 5.607 million square miles this year; the lowest on record according to NASA.
With 13 of the smallest maximums recorded in the last 13 years, Walt Meier, a sea ice scientist at NASA’s Goddard Space Flight Center sees a trend:
“It is likely that we’re going to keep seeing smaller wintertime maximums in the future because in addition to a warmer atmosphere, the ocean has also warmed up. That warmer ocean will not let the ice edge expand as far south as it used to… Although the maximum reach of the sea ice can vary a lot each year depending on winter weather conditions, we’re seeing a significant downward trend, and that’s ultimately related to the warming atmosphere and oceans.”
Coming on the back of February’s highest global temperature on record, shrinking sea ice raises the prospect of another feedback loop in which more water vapour (a greenhouse gas) evaporates into the atmosphere above the Arctic, further increasing the temperature and accelerating the loss of ice.