Let us explain about green house gases
Step-by-step explanation:
Green house effect 
It can be explained as :
- The sun emit radiations that consist of infra red rays , ultra violet rays and visible light .
 - The infra red rays (responsible for heating ) when come from sun , it travels through atmosphere and reaches earth surface .
 - On striking the earth surface , it gets reflected and reflected infra red ray has greater wavelength .
 - Then this reflected rays moves back through atmosphere .
 - On doing so , they encounter certain gas molecules like carbon dioxide , methane etc .
 - This gases absorb these rays and do not let them to escape through them .
 - As a result, they get trapped .
 - As we have already mention that they cause heating effect , due to this property they raise the temperature of atmosphere leading global warming .