## Climate Conclusions: The American Petroleum Institute (1980)

The following are excerpted from a memorandum quoted by the Inside Climate News team, documenting the minutes of a 29th February 1980 of a task force on climate change at the American Petroleum Institute.

Hat tip to Climate Denial Crock of the Week. Emphasis added by me. I have also taken most of the text and reduced it to mixed case rather than the all upper case in the original document.

CLIMATE MODELING — CONCLUSIONS

• Global averaged $2.5\textdegree$ C rise expected by 2038 at a 3% p.a. growth rate of atmospheric $\text{CO}_{2}$ concentration
• Large error in this estimate — 1 in 10 chance of this change by 2005
• No regional climate change estimates yet possible
• Likely impacts:
• $1\textdegree$ C rise (2005): barely noticeable
• $2.5\textdegree$ C rise (2038): major economic consequences, strong regional dependence
• $5\textdegree$ C rise (2067): globally catastrophic effects

Note the proper interpretation of uncertainty when they quote “1 in 10 chance of this change by 2005”. The task force clearly understood that one wants to consider the worst possible impacts, not the least. Elsewhere in the document, the task force reports that:

• $\text{CO}_{2}$ “doubling” date is 2038 at a 3% p.a. growth of atmospheric release rate
• Error in this estimate is small compared with other sources of error

They also note

• Strong empirical evidence that rise caused by anthropogenic release of $\text{CO}_{2}$, mainly from fossil fuel burning