Green house gasses are carbon dioxide that traps the sun’s rays in the atmosphere which traps the heat in the atmosphere.
Lots of green house gasses are emitting into the Earth’s atmosphere because of coal being burned and other fossil fuel used. If more heat gets trapped in the atmosphere the polar ice caps and glaciers will melt which could flood various places making it uninhabitable. Trees are turning the CO2 into oxygen but people are cutting down trees to make land for farmland. In places such as Brazil rainforests are disappearing.
Green house gases will make the world warmer if we don’t act quickly and stop people cutting down trees.