This is a side-commentary on the physics of the greenhouse effect and some “popular” ideas and words which don’t quite get at the actual physics of the problem.
First of all, temperature does not increase with greater greenhouse effect because “less heat gets out”, at least not in the sense that people intuitively believe. That is, it isn’t really as if extra solar heat is being “stored” somewhere (though oceans will take some) and that’s why it’s hotter.
The total amount of outgoing energy from the Earth is extremely well balanced by the total ingoing energy to the Earth from the Sun (plus a tiny bit from the cosmic background), and this stays so even with a greater greenhouse effect. The notion of “trapping heat” is thus somewhat imprecise.
What is happening is that with greater greenhouse gases some of the radiation reflected from the Earth’s surface hits the upper atmosphere, excites some molecules, which then re-emits in a random direction, which half the time is back down, which of course will be partially aborbed, reflected and re-emitted. This continues the cascade until you again reach equilibrium in the total energy in equals total energy out. (ignoring ocean heat capacity).
A hotter surface does of course radiate back out MORE energy.
However, the equilibrium temperature is higher when there is more greenhouse gas.
The best way to think about it is this:
Without greenhouse gases, looking up from the Earth’s surface your source is the energy from the Sun, principally in visible frequencies. With the greenhouse effect, you add in another source in the infrared. Increase the greenhouse gases and this second source gets more important.
This is not exactly how a real ordinary gardener’s greenhouse works (completely)—there a significant effect is that you insulate your plants from strong heat losses from convection of air.
