Environment.

Air pollution by a mixture of smoke and fog.

An effect in which heat is kept inside the Earth by some gases such as carbon dioxide or methane.

A tropical forest with high annual rainfall.

The shaking from the movement of rock beneath Earth's surface.

Disappearance of a species and they no longer exist.

The issue of having to many people in a place

The process of useful land becomes dry desert as a result of deforestation or not having enough rain.

An extreme shortage of food.

The pollution of water from industrial waste

A rapidly spreading and usually fatal (serious) disease.

A long period of dry weather.

Rain that contains more acid than normal.

The decrease of trees in the forest due to human actions.