As I write, the temperature in New York City is 86° F. The relative humidity is 56, the winds are south-westerly at seven mph, visibility stands at six miles. What do those numbers really signify? The temperature doesn't sound extreme, yet when I leave my air-conditioned house I don't feel that I'm stepping outside so much as entering another atmosphere. My spirits sag, my lips soon taste of sweat. Is this 86°? Well, yes, because that's what the New York Times says it is. On the other hand, as any schoolchild knows, what really matters is the humidity, and the increasing capacity of air to retain moisture as its temperature rises.

LRB 22 August 2002 | PDF Download