Pictured: California’s smoky Labor Day Weekend 2013. Smoke isn’t a new phenomenon. Here is a newspaper article describing smoke 165 years ago:
Unusual Phenomenon – LOS ANGELES STAR – April 20, 1851
It is now about six days that we have in this and the surrounding country been the spectators of unusual phenomenon, which, from its peculiarity, has given occasion to manifold surmises, conjectures, speculations and rumours. The atmosphere has been so filled with smoke as to confine the vision within a small circumference. And as the smoke was wanting in those aerial properties which affect the eyes and nostrils, there were not many who denied the assertion that it was smoke.
CALIFORNIA SMOKE & POLLUTION (STATS)