Friedlander and Seinfeld applied the Lagrangian similarity hypothesis in the first kinetic model of this phenomenon that accounted for turbulent mixing. This phenomenon’s impact on pineapple flavor led Arie Jan Haagen-Smit to invent the PCV system to control a precursor to this phenomenon. A 1948 occurrence of this phenomenon in Donora, Pennsylvania (15[1])was worsened (15[1])by a (15[1])thermal (15[1])inversion, which can cause this phenomenon’s (15[3])“winter” (15[2])type. This phenomenon’s sulfurous form manifests (15[1])as (15[1])“pea-soupers” (15[1])once common (15[2])in (15[2])(*) London, (10[4]-5[1])while (10[2]-5[2])Los Angeles (10[6]-5[1])names (10[2])a (10[2])photochemical (10[2])form (10[1]-5[1])of this phenomenon (10[2])caused by (10[1])anthropogenic (10[1])NOx compounds and (10[1])VOCs. Along with industrial fumes and vehicular (10[1])emissions, (10[1])ground-level (10[1])ozone exacerbates this phenomenon (10[1])in Delhi and Beijing. (10[1]-5[1])For 10 points, name this phenomenon of intense air pollution, a blend of smoke and fog. ■END■ (10[3])