<span>absorption spectra is your answer. i had the same multiple choice question last year</span>
The greenhouse effect occurs when rays enter our atmosphere and are reflected from the ground up. They get changed during their voyage through our atmosphere and they change in such a way that they can't leave the atmosphere anymore. Then they stay inside and heat up the planet which causes thing like global warming. That's what the greenhouse effect is.
The difference between temporary and permanent is temporary will only last a little while, permanent on the other hand lasts forever