Those of you in the know realize that farts are primarily methane but methane itself is odorless. It is sulfur compounds, and chiefly in farts, hydrogen-sulfide, which give farts their aroma.
Humans can detect concentrations of hydrogen sulfide at approximately 5 parts per billion. A typical fart will have between 1 part per billion (undetectable) and 300 parts per billion (maximum rank).
Something goes amiss when concentrations run above 300 parts per billion, our noses lose their ability to detect the smell. Concentrations above 1 part per million over an hour are hazardous to our health.
Here is an often unrecognized hazard of global warming that many are unaware of. As temperatures rise, the ability of our oceans to retain dissolved oxygen decreases. And as we add various nutrients such as nitrogen and phosphorous and iron to our oceans, surface algae bloom and their corpses, as they fall, consume all the remaining oxygen below.
In the absence of oxygen, anaerobic bacteria, that primarily derive their energy from reacting hydrogen with sulfur, bloom. These bacteria produce, as their waste product, hydrogen sulfide. If the oxygen depletion is severe enough these bacteria will multiply to the point where they first make our atmosphere smell really bad, and then make our atmosphere kill us, and most other forms of life on land.
So just another reason you might want to give up that hummer and buy a Prius.
I’m just saying.. To me death by giant fart just seems an unpleasant way to go. It is predicted that ocean oxygen levels will change significantly in the next 15-25 years. When you start smelling fart everywhere you go, it is the beginning of the end.