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Thursday, Apr. 8, 2021

Is carbon dioxide a pollutant?

John Cook, Skeptical Science
yes

Increased atmospheric CO2 from human activities is warming the planet. This poses many threats, including more extreme and destructive weather events, expanded disease vectors, biodiversity loss, and sea-level rise, which could displace billions of coastal dwellers.

The Clean Air Act mandates that the U.S. Environmental Protection Agency keep a list of pollutants that “may reasonably be anticipated to endanger public health or welfare.” In 2007, the Supreme Court ruled that CO2 and other greenhouse gases are pollutants that may be regulated by the EPA.

The misconception that CO2 cannot be a pollutant because it helps plants grow oversimplifies its impact on the climate, which includes the aforementioned threats. Additionally, while more CO2 spurs photosynthesis and reduces water loss in crops, it also exacerbates drought and desertification, making its long-term impact on agriculture unclear.

Sources

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Fact briefs are bite-sized, well-sourced explanations that offer clear "yes" or "no" answers to questions, confusions, and unsupported claims circulating online. They rely on publicly available data and documents, often from the original source. Fact briefs are written and published by Gigafact contributor publications.

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Skeptical Science is a non-profit science education organization. Our goal is to remove a roadblock to climate action by building public resilience against climate misinformation. We achieve this by publishing debunking of climate myths as well as providing resources for educators, communicators, scientists, and the general public. Skeptical Science was founded and is led by John Cook, a Senior Research Fellow with the Melbourne Centre for Behaviour Change at the University of Melbourne.

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