THE DECLINE OF ANTARCTIC SEA ICE AS A FIVE-SIGMA EVENT
It has been confirmed that during the winter of 2023, the sea ice around Antarctica is in sharp decline. Experts are now concerned it may not recover.
Why is sea ice important? What has it got to do with a Five-Sigma Event? This might hurt your brain but hang in there…
First and simply, sea ice helps regulate Earth’s temperature. The ice reflects the Sun’s heat back into space, helping to regulate the temperature of the planet. Second, the annual cycle of freeze and melt drives global currents that transport nutrient-rich water into the rest of the ocean, feeding ecosystems. Physical oceanographer Edward Doddridge says vast regions of the Antarctic coastline were ice-free for the first time in the observational record. He says this is a five-sigma event.
What is a Five-Sigma Event?
The elusive “five-sigma event” represents a level of significance that researchers strive to achieve in experimental results, indicating a confidence level of 99.99994%. A five-sigma discovery has far-reaching implications. In scientific research, achieving a five-sigma standard is no mean feat. It implies that the odds of the observed data arising purely by chance are less than one in 3.5 million. Dr. Doddridge says that means, if nothing had changed, we’d expect to see a winter like this about once every 7.5 million years.
Consequently, a five-sigma event is synonymous with groundbreaking discoveries. Scientists are trying to work out what is causing the decline in sea ice. Is it natural variability? Or is climate change responsible? Dr Doddridge says it is more likely the latter. Yep, you guessed it!
So, together let’s reduce emissions to close to zero to help the ice stay icy, one blizzard at a time.
Strong brain nectar:
The concept of sigma, rooted in statistics, refers to the number of standard deviations by which a measured value deviates from the average. A one-sigma event implies a 68% confidence level, while a two-sigma event corresponds to about 95%. As we progress to three, four, and eventually five sigma, the confidence levels reach 99.73%, 99.994%, and 99.99994%, respectively.
References:
<https://www.abc.net.au/news/2023-07-24/antarctic-sea-ice-levels-nosedive-five-sigma-event/102635204>
