Fast Company on the Five-Sigma Event

Antarctic Sea Ice Sees Record Low Growth

Earlier this summer (for those of us in the northern hemisphere), as Antarctica reached it’s peak winter season, scientists observed what came to be known as a “five-sigma event” in Antarctic Sea Ice. This referred to the unprecedented record low maximum sea ice extent observed this year, which far surpassed previous records.

Oscar Schofield, the PAL LTER Principal Investigator, was one of many PAL scientists who were asked by the media to comment on this event and it’s possible impact on the Antarctic ecosystem.

Here is a snipped from an article in Fast Company

“What we’re seeing this year we’ve never seen before,” says Oscar Schofield, chair of the Marine Science Program at Rutgers University and one of the principal investigators for Palmer LTER, a Long Term Ecological Research site on Antarctica. “Unless something dramatic happens in late winter, which I’m not expecting, this will be the lowest year ever recorded for sea ice.”

The decline is so extreme that researchers have been calling it a “five-sigma event,” basically referring to how many standard deviations it is beyond the mean: “It’s like, okay, we’re five times outside of deviations,” Schofield says, “so it’s an extreme event.”

“If you change the state of the Southern Ocean, there’s great potential for it to have big ramifications on planetary carbon, biogeochemistry, and all those kinds of things,” Schofield says. “There are a lot of discussions going on now about, what does a super-low-sea-ice year like this mean?”

You can read the full article here…

What is a 5-sigma event? Why the sea ice in Antartica is alarming scientists
By Kristin Toussaint, July 27, 2023

Image from NASA Earth Observatory