The Earth has experienced a constantly changing climate in the time since plants first evolved.

Earth had certainly experienced enough of that kind of strife in its history before achieving a unity of purpose.

It is conceivable that the Earth is currently experiencing something similar to this, skeptics say.

Earth has experienced climate change in the past without help from humanity.

In 1953, Earth experienced a War of the Worlds.

A riddle is why the microbe's skills evolved, since Earth apparently never experienced such high levels of radiation.

The military's contribution to this victory would bring them unprecedented honor and the Earth would finally experience universal, uninterrupted peace.

The Earth has undergone tremendous change in the past and is experiencing similar change now.

What would happen if the Earth experienced another ice age?

But long before then Earth may be experiencing catastrophic distress.