Fact Brief – Does breathing contribute to CO2 buildup in the atmosphere?

Posted on 18 May 2024 by SkS-Team

Skeptical Science is partnering with Gigafact to produce fact briefs — bite-sized fact checks of trending claims. This fact brief was written by Sue Bin Park in collaboration with members from our Skeptical Science team. You can submit claims you think need checking via the tipline.

Does breathing contribute to CO2 buildup in the atmosphere?

The CO2 we breathe is part of a balanced carbon exchange between the air and the earth. In contrast, burning fossil fuels injects CO2 into the atmosphere that has been stored underground for millions of years, causing a rapid buildup.

Fast cycling of carbon is seasonal. CO2 increases in colder months when plants decay and release their carbon. In the warmer months, CO2 decreases as plants take it in, along with sunlight, to produce energy and oxygen. Animals — including humans — eat plants, breathe in oxygen, and exhale CO2. Graphs of CO2 show a wave pattern reflecting this seasonal change.

Fossil fuels are part of the slow carbon cycle that operates over geological timescales. Burning fossil fuels takes carbon stored in the slow cycle and introduces it into the fast one. This activity is unique in Earth’s history; no other life-form has done anything on the same scale.

Go to full rebuttal on Skeptical Science or to the fact brief on Gigafact

This fact brief is responsive to conversations such as this one.

Sources

MIT Climate Portal Does the carbon dioxide that humans breathe out contribute to climate change?

US San Diego The Keeling Curve

McGill University Office for Science and Society Why isn’t the carbon dioxide from breathing a concern for global warming?

About fact briefs published on Gigafact

Fact briefs are short, credibly sourced summaries that offer “yes/no” answers in response to claims found online. They rely on publicly available, often primary source data and documents. Fact briefs are created by contributors to Gigafact — a nonprofit project looking to expand participation in fact-checking and protect the democratic process. See all of our published fact briefs here.