Here’s my eighth Cranky Uncle video, debunking the myth that CO2 has followed warming in the past so CO2 can’t cause warming. This animated video is adapted from cartoons in the Cranky Uncle vs. Climate Change book.
When we burn fossil fuels, we release carbon dioxide into the atmosphere. Carbon dioxide, or CO2, is a heat-trapping gas and causes warming. But when it gets warmer, the oceans release CO2. This is because warmer water _ can’t hold as much dissolved CO2. This results in more CO2 in the air _ which results in more heat being trapped and more warming. So more CO2 causes warming, and warming causes more CO2—a reinforcing feedback.
In the past, when the Earth warmed due to factors like wobbles in the Earth’s orbit, this caused the oceans to release more CO2. The extra CO2 in the atmosphere added even more warming. This reinforcing feedback was strong enough to pull the Earth out of ice ages. Over the last half million years, climate and CO2 marched together in lock-step. But Cranky Uncles look at past climate change and come to the wrong conclusion. They argue that in the past, CO2 rose after warming, therefore CO2 can’t cause warming. This commits the logical fallacy known as false choice, otherwise known as false dichotomy.
A false choice is where you have to choose only one of two options, when both options could be correct or there could be other options. In the case of CO2 and climate, we know that more CO2 causes warming and warming causes more CO2. Both options are correct.
The false choice fallacy is like arguing that either eggs come out of chickens or chickens come out of eggs. In reality, both are true. Arguing you have to choose one or the other is a false choice.
If you want to delve into this myth in greater detail, we debunk the myth “CO2 lags temperature so CO2 can’t cause warming” at Skeptical Science. We also debunk the myth in our MOOC Denial101x: Making Sense of Climate Science Denial:
Check out the full list of Cranky Uncle videos on YouTube.
P.S. – this video is my first attempt at genuine character animation (clumsily done but be forgiving, it’s my first go). Here’s a GIF of the animation (you never know when you’ll need a GIF to illustrate how CO2 and climate have marched in lockstep during Milankovitch cycles):
Leave a Reply