One of the great environmental and human-health success stories of the past 50 years has been the improving quality of America’s air.  Acid rain is less acidic than it was a generation ago and particles harmful to human health are less concentrated in our air.  But that is not to say that air quality is especially good in all parts of the country, all of the time.  The picture below was taken on my way home to Davis (well, the Sacramento airport) from a conference in LA.  The picture is taken looking east at the southern end of the Central Valley as the sun was setting.  This particular setup, with the sun behind me and my looking far off to the east, results in a particularly hazy looking picture.  If you’re interested to know why, please take ATM 128.  But, getting back to my point, individual locations in the US are still susceptible to conditions that result in poor air quality.  Unfortunately, the Central Valley is one of those places.

(Disclaimer: I do not endorse Southwest or any other particular airline)