Living creatures sometimes speak to the outside world. They can be looking for a mate, or shouting warnings. Sometimes they merely express content, such as when a cat purrs.
So why do crickets chirp? Count the number of times a cricket chirps in 14 seconds. Add 40, and you'll get the temperature in Fahrenheit, according to the Farmer's Almanac. Does temperature truly motivate a cricket to express itself?
According to Snopes, male crickets are the chirpers, doing mating calls. This only happens when the temperature is at least 55 degrees. Apparently, they aren't in a loving mood when it's cold.