When faced with reports about the climate crisis, many people can’t conceive just how much impact human activity has made on the earth’s atmosphere. Here’s a new way to understand it: compare today’s crisis to past catastrophic events.
A research team did just that, performing an analysis using well-accepted atmospheric and geological data from around the world. Their conclusion:
The total amount of human greenhouse gas (GHG) emissions in the atmosphere is comparable to the material ejected by the planet’s largest asteroid collisions and volcanic events from eons ago.
Hal Nelson, PhD, Associate Professor at Portland State University, led the team for this “thought experiment” analysis which was just published in the scientific journal Anthropocene Review. The paper compared the mass of human-produced greenhouse gases (GHGs) to the mass of material kicked up by historical planetary events, particularly asteroid strikes and volcanic eruptions. Here are some top-line findings:
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If it had been produced by a volcano, the mass of human-produced GHG emissions would rank as an 8 (“mega-colossal”) on the 0–8 Volcanic Explosivity Index.
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If an asteroid strike produced as much matter as human GFG emissions have, that asteroid would be considered “. . .capable of causing global climatic catastrophe”.
This infographic paints the picture. There’s much more information in the paper “The carbon crater: Comparing anthropogenic greenhouse gas emissions to historical planetary events.”
Now when you need to help someone understand the impact that human-caused GHGs can have on our planet, you have an answer.
If you'd like more information from Dr. Nelson, you can reach him at 503.236.6720 or hnelson at pdx.edu.