Myth Deconstruction - Lag (EN)

Reference

Deconstructing climate misinformation to identify reasoning errors
Cook, J., Ellerton, P., & Kinkead, D. (2018). Deconstructing climate misinformation to identify reasoning errors. Environmental Research Letters, 13(2), 024018. Link to PDF & Link to Supplement

Step-by-step deconstruction

The table below is inspired by the simplified supplement and may differ slightly from what is shown in the GIF. This is mostly due to make the text fit into the available space which made it necessary to reword some of it.

1 Identify claim Atmospheric CO2 lagged behind temperature changes in the past, so rising CO2 can't be the cause of rising temperatures.
2 Argument structure Premise 1: If CO2 causes global warming, then CO2 variations should precede temperature variations.
Premise 2: CO2 lags temperature in the past.
Conclusion: CO2 cannot be the cause of global warming.
3 Inferential Intent

Deduction

4 Validity VALID
4a Hidden premises NONE
5 Check premises Premise 1 is false: false choice. While it is true that CO2 causes global warming, that doesn't mean global warming might not also lead to increased CO2 in the atmosphere. Moreover, increases in global temperatures can lead to the release of large amounts of CO2, which then exacerbates the process. The relationship between to two is therefore not so simple.

Premise 2 is false: slothful induction. While it is true in the Antarctic ice core record that CO2 lags temperature, it is not the case in Greenland ice cores or tropical ocean sediment cores. Consequently, it's false to say that CO2 always lags temperature. It's a regional phenomena restricted to Antarctica.
6 Status of claim FALSE
The argument is valid but the premises are false.
7 Summary of fallacies False choice: While it is true that CO2 causes global warming, that doesn't mean global warming might not also lead to increased CO2 in the atmosphere. Just because a chicken comes from an egg doesn't mean eggs don't come from chickens—both are true. Similarly, CO2 causes warming and warming causes more CO2. The two combined comprise a reinforcing feedback.

Slothful induction: While CO2 lags temperature in the Antarctic ice core record, that is not the case in Greenland ice cores or tropical ocean sediment cores. Consequently, it's false to say that CO2 always lags temperature. It's a regional phenomena restricted to Antarctica.

Related material

CO2 lags temperature - what does it mean?

Blog post with background information about the myth deconstructions: Myth deconstructions as animated gifs

To learn more about the fallacies used in the myth deconstructions: A history of FLICC: the 5 techniques of science denial


Other versions


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