People who say that greenhouse gases don’t warm the atmosphere, shouldn’t use microwave ovens. Because they believe that “a cooler object can not warm a warmer object.”
Microwave ovens use the same principle as the greenhouse effect – generating heat by absorption of electromagnetic radiation. Astonishing that some people are incapable of accepting the basic science which they take advantage of every day.
The troposphere has a fairly linear temperature gradient. If you increase the temperature in the upper troposphere by adding greenhouse gases, you will necessarily raise the temperature in the lower troposphere too. The entire line will shift upwards.
