“Five-nine” doesn’t have quite the cadence as “nine-eleven,” but when we look back on the early 21st century, I believe that May 9, 2013 — the day the concentration of carbon dioxide in the atmosphere exceeded 400 parts per million for the first time in recorded history — may in the future be understood as a far more important date than September 11, 2001. It may even be that 5/9 will be seen as the long-anticipated tipping point at which human impacts caused irrevocable harm to our planet.
Read the rest of Aaron Ellison’s post here