Five Sigma threshold crossed for Global Warming
What the heck is “Five Sigma?”
The online publication Earther recently reported the strengthening of the statistical case for global warming based on satellite data. If you find Earther’s Evidence for Global Warming Passes Physics’ Gold Standard Threshold readily comprehensible, then you need not read most of this post. (The “Gold Standard” is five sigma.)
If you have been pretty satisfied with the Earther article, I invite you to skip way down to the section “Three further notes of clarification [etc.]“
If Earther’s piece is not easily comprehensible, that’s probably because writer Daniel Kahn did not explain just what “five sigma” means statistically. My hunch is that 30% of my readers will understand and remember it, another 45% understood it in the past but have forgotten a lot of it, and the remaining 25% may never have had it presented to them. If you belong to the latter group, don’t blame yourself—blame the scattershot American education system.
Simply said, “five sigma” comes down to we have zillions of measurements and 99.99994% of them confirm that global warming is real. There is an item of faith here: you have to trust that NASA has amassed enough data over a long enough period of time to meet the requirements of a statistical analysis. My “zillions of measurements” encapsulates that faith to my satisfaction. Very scientifically of course. (Well . . . The Shorter Oxford English Dictionary defines zillion as “a very large but indefinite number.”)
Does understanding “five sigma” matter?
It matters if you’d like to have a scientifically bulletproof case for the existence of global warming. Don’t you want bulletproofness?
Continue reading “Statistical Case for Global Warming Approaches Certainty”