I love it when people care enough to educate me and hopefully members of the Mrs. Green community about issues I talk about whether it be on the radio or in the written word.  So thanks to Beth Gorman from the Department of Environmental Quality for the following information.  Beth is an amazing person and is REALLY an expert on any number of topics.

Beth writes:

“There is an air pollutant called “ground-level ozone” (as opposed to the ozone layer above us that protects us from the sun’s radiation). Ground-level ozone is created when gasoline fumes, car exhaust, and other pollutants that are floating around in our air “bake” together in the presence of intense summer heat and sunlight. The technical term for the “baking” is called a “photochemical reaction.”  If we refuel while the sun is up during the hot summer months, we release gasoline fumes that can react with the sunlight and other pollutants to form ozone. When we refuel after the sun has set, the gasoline fumes that are released into the air will not have the intense sunlight available to begin that photochemical reaction, so our ozone levels will be lower.  Does that make sense?
AirInfoNow.org (our air quality website) has lots of good info. An activity that shows how ozone is made http://www.airinfonow.org/html/makingozone/o3play.htm  and information on the health effects of ozone http://www.airinfonow.org/html/ed_ozone.html as well as a mapping system that shows ozone as levels are increasing across our community http://www.airinfonow.org/html/ozoneMC.html.”
Thanks Beth.  And yes, it makes sense.  Scarey, I know.