For example, when carbon dioxide levels increase in the atmosphere, plants grow more quickly.

During this period, another process must be involved in controlling carbon dioxide levels.

In a year or maybe even less, they'll start noticing the carbon dioxide levels going down.

Every morning his blood is drawn to test the oxygen and carbon dioxide levels at a cost of $93.75.

The carbon dioxide levels were roughly 16 times higher than today.

China says rich countries bear responsibility for the increase in global carbon dioxide levels that has already taken place.

Before the industrial revolution, the carbon dioxide level was about 280ppm.

The carbon dioxide level is rising because we are burning things.

The soil also lost nutrients at the high carbon dioxide level.

In such a case, carbon dioxide levels should be slowly diminished.

For example, when carbon dioxide levels increase in the atmosphere, plants grow more quickly.

During this period, another process must be involved in controlling carbon dioxide levels.

In a year or maybe even less, they'll start noticing the carbon dioxide levels going down.

Every morning his blood is drawn to test the oxygen and carbon dioxide levels at a cost of $93.75.

The carbon dioxide levels were roughly 16 times higher than today.

China says rich countries bear responsibility for the increase in global carbon dioxide levels that has already taken place.

Before the industrial revolution, the carbon dioxide level was about 280ppm.

The carbon dioxide level is rising because we are burning things.

The soil also lost nutrients at the high carbon dioxide level.

In such a case, carbon dioxide levels should be slowly diminished.