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Let's address an important misconception. “Greenhouse gases” (abbreviated GHGs) do 𝒏𝒐𝒕 trap heat. When a scientist says that we are emitting ‘heat-trapping’ gases into the atmosphere by burning coal, oil and natural gas, that's just plain wrong. In an actual greenhouse, there is no convection. The glass acts as a physical barrier to prevent convection from taking heat and ventilating it out of the system. In the Earth's open, convective atmosphere, there is no ‘lid’ or physical barrier that inhibits infrared radiation (IR) from escaping into outer space, and because of that, we have convective overturning which is a very [and often overlooked] part of the energy budget in the diagrams you see published in textbooks. What GHGs actually do is absorb and emit photons of radiation in the IR portion of the electromagnetic (EM) spectrum. Upon collisions with other molecules, their polyatomic structures allow them to bend or rotate in such a way that they become “IR-active.” But, they are only IR-active if they generate dipole moments. Gases like H₂O, CO₂ and CH₄ generate dipole moments and thus can absorb and emit photons of IR. Diatomic N₂ and O₂, which constitute the bulk atmosphere, do not interact with IR since they lack dipole moments due to their structural symmetry. The GHGs absorb IR, and then emit it. They reduce the rate of radiative cooling; they don't stop it. Therefore, it isn't “heat-trapping.” This distinction is important.