Antarctic sea ice has usually been able to recover in winter. But this time it's different, with levels taking a sharp downward turn at a time of year when sea ice usually forms reliably — and experts are worried.
For seriously though, its explained in the article:
For those of you who are interested in statistics, this is a five-sigma event. So it’s five standard deviations beyond the mean. Which means that if nothing had changed, we’d expect to see a winter like this about once every 7.5 million years.
Sigma balls. Am I doing this right?
For seriously though, its explained in the article: