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Misconception: Severity

CO2 makes up a small fraction of the gases in the atmosphere, but is very powerful

About 99% of the Earth’s atmosphere is made of just two gases: oxygen and nitrogen. By comparison, the amount of carbon dioxide — which at more than 400 parts per million, is the highest it’s been in several million years — may seem small. It’s equivalent to just 0.04% of the atmosphere.

This fact is often cited by people who are trying to falsely claim that CO2 isn’t responsible for global warming. These individuals also often add that the amount of CO2 from humans is just a fraction of that already small total. 

How can carbon dioxide be harmful if it’s ‘plant food’?

The notion that carbon dioxide is “plant food” and that climate change is therefore a good thing or not a problem is a common refrain from those who deny the reality of climate change or who oppose reducing greenhouse emissions.

It’s true that carbon dioxide, the main heat-trapping gas that is causing global warming, is essential for plant growth. Most — but not all plants — tend to respond to increased levels of CO2 by growing more. 

But more CO2 is not always good.

Warming Beyond 1.5 C Harmful, But Not a Point of No Return, as Biden Claims 

Warming Beyond 1.5 C Harmful, But Not a Point of No Return, as Biden Claims 
April 27, 2023

It’s increasingly likely that the planet will reach 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, of warming, probably within the next two decades. But while that level of warming comes with a variety of dangerous effects, it’s not a point of no return, scientists say, and it doesn’t mean “we’re done,” as President Joe Biden has claimed.