Without that, the Earth would be cooling towards a new 'ice age' - a glacial stage, to use the better term.
We know this because most of the things that cause glacial stages are regular patterns of movement by the Earth as it orbits the Sun.
The ice would start to return in around 1,500 years, but only if there was a lot less carbon dioxide in the air.
So is it a good thing that a lot of carbon dioxide is being made?
No.... the CO2 needed to hold back the ice was made by simple things like farming long before the Industrial Revolution.
The huge amount made over the last 150 years has taken things to a different situation, where very fast warming is happening.
This is going to change all kinds of things.
Atmospheric CO2 is now just below 400 parts per million (ppm) on average.
That has not happened since the Pliocene (5.3-2.6 million years ago).
At that time, temperatures rose to levels 2-3°C warmer than today.
Sea level rose by up to 20 metres (65 feet) in places.
It was a very different world.