As the Earth cools, it changes from hot white to red to blue.

Whether the earth has warmed and cooled isn't the issue.

Past history shows us that the Earth has warmed and cooled many times with the influence of man.

And because there is less carbon dioxide in the atmosphere, the Earth would cool.

For several years the earth cooled and settled, producing many local earthquakes.

Throughout its long history, Earth has warmed and cooled time and again.

It was the following morning before the earth had cooled sufficiently for the skinners to go out to work.

In Darwin's lifetime, physicists did not know about radioactivity, and therefore thought that the earth would cool down rather quickly.

By the beginning of the Archean, the Earth had cooled significantly.

Let's not forget that the earth has warmed and cooled for hundreds of millions of years.