They claim that the surface of the earth is smoother than a ping pong ball, in relative terms. How could microscopic – nanoscopic activities possibly effect this?
But yet, driving down to LA from the mountains there is a yellow-brown haze, static, unnatural, thick, and sickening. Acid rain, CFC, nuclear fall out, all products of volcanic, meteors, or other natural phenomenon. However the “smoke-oil-gas” was mainly attributed to poorly regulated night time refining of the local petrol. Not as bad as it used to be, sure it still is a problem, in areas like the lower San Joaquin valley, where the San Francisco green people’s pollution tends to gather, over the farmland, bottled up by the Sierra Nevada mountains.
So believe what you want, but, some areas of this nano-scopic human activity has demonstrated, and is widely recognized, as having a negative impact on the air quality.
Just walk on a sidewalk in Caracas, as a herd of two stroke mopeds putter past. You can just watch the blue-green haze, float in the air, like the ever present demons of my mind.