95 degrees and you’re stopped in traffic on an August afternoon. Sweat drips from your neck all the way down your back until your shirt absorbs it, making a damp spot between you and the seat. Your legs are either stuck to the vinyl upholstery or leather seat covers. Your hands feel like they're about to slip off the steering wheel, and you're thankful your eyebrows are keeping the sweat from running into your eyes. Well, mostly. What's missing from this picture? Automotive air conditioning. It's become nearly universal, with 99 percent of all new cars as of summer 2014 coming equipped with it. When it's missing, we notice.