Heat: A factor or not in ground-level ozone formation? Addressing the uncertainty

By now, ground-level ozone is a subject most everyone is familiar with – it is more commonly referred to as smog. But, I would say, what most people probably are unsure of is what exactly it is that feeds it. In other words, what makes ground-level ozone form in the first place?

Well, what I know about how ground-level ozone forms, this is based on the correct combination of factors or ingredients being present and these so-called ingredients are: hydrocarbons (HC), oxides of nitrogen (NOx) and sunlight.

That said, I’ve seen it written in different places (in a variety of sources, in other words) and I’ve even written it myself, that, among those ingredients, heat is included also.

So, which is it: Is heat a factor or not? Well, is it or is it not?

Alright, so, I had heard or read a report somewhere, sometime, though I can’t put my finger on it exactly, but, I remember an instance during one really hot summer day that ground-level ozone and therefore smog formed in the Fresno sky.

Well, the fact of the matter is, after the temperature had reached I think 110 degrees, that would be Fahrenheit, poof! The ground-level ozone, and consequently the smog, were gone. Amazingly, the skies had cleared.

Now, in sizing this up, some might be inclined to think that I might be making this stuff up as I go or that this is the stuff that dreams are made of. But that could not be farther from the truth. This is something that is not without merit – it really did happen!

And, being that it did transpire, this leads to my asking whether or not heat is a factor in ozone’s formation/dissolution, meaning how it could at the same time also be a factor in its disappearance.

From my recollection, what I remember was this being a one-time occurrence. But, that it happened at all, it really makes me wonder – I’m puzzled by it all.

All of which leads me to believe that it isn’t heat per sé that ozone – among the key ingredients which are necessary for ground-level ozone to form – requires.

That all said, let’s be clear: If someone reading this has a definitive explanation, I’d sure like to hear it, if for no other reason than this matter relating to ground-level ozone formation being cleared up once and for good.

Just so you know, I looked up the word “ozone” in the Random House Webster’s College Dictionary (1991 edition) and as it relates to what is being discussed in this thread, in my opinion, and sorry for the pun, but, honestly, it doesn’t shed any useful light.

I would like nothing more than to have this matter settled once and for all.

A smoggy New York

Image above: Dr. Edwin P. Ewing, Jr., Centers for Disease Control and Prevention

– Alan Kandel