The greenhouse effect is rightly called that because greenhouses allow heat to enter, but doesn't allow heat to leave, which warms plants.
On earth however, it's much bigger. Our own atmosphere acts similarly to this; it allows heat in, but doesn't allow it to leave which heats up the planet and causes global warming.
I hope this is the answer that you are looking for .
Groups IVB–VIII, IB, and IIB, or 4–12
