How Two Scientists Accurately Predicted Global Warming in 1967 (medium.com)

Slashdot reader Layzej shares an article from this spring marking the 50th anniversary of the first accurate climate model: Astrophysicist Ethan Siegel looks at a climate model (MW67) published in 1967 and finds "50 years after their groundbreaking 1967 paper, the science can be robustly evaluated, and they got almost everything exactly right."

An analysis on the "Climate Graphs" blog shows exactly how close the prediction has proven to be: "The slope of the CO2-vs-temperature regression line in the 50 years of actual observations is 2.57, only slightly higher than MW67's prediction of 2.36" They also note that "This is even more impressive when one considers that at the time MW67 was published, there had been no detectable warming in over two decades. Their predicted warming appeared to mark a radical change with the recent past:"

Comments

Actual science

[jandrese]

This paper is arguably the origin of the modern disinformation campaign against carbon pollution. This is the point where politically powerful interests realized that their core business model was in danger and that they needed to do something to stop it. Now we have an entire political party who's official position is to ignore the blatantly obvious and to be actively hostile to the kind of research that produced this paper.

Re:Actual science

[Oceanplexian]

I'm a trader and read a lot into statistics. It's quite interesting how most people quickly jump to conclusions based on bad data.

Just because you can predict something, does not mean you can repeatedly predict it, or that your prediction implies a pattern. Investors tend to lose their shirt on a regular basis thinking they can time the market, even with rock solid data. Even predictions that can be replayed on historical data, frequently fail when applied on new, future data. I can virtually guarantee if you tried to apply the same model to an expanded data set it would be a hell of a lot less conclusive. Unfortunately the blogger that posted this has neglected to apply the model to the last 1,000, or 10,000 years, and has instead decided to come to conclusions based on 0.0001% of the actual data we should be looking at. This, too, is a common tactic, intended to obfuscate the facts and imply that carbon pollution is a much more serious threat than it actually is.

Re:The coming Ice Age

[hey!]

Yes. Because science doesn't dabble in truth, it deals with evidence, and likelihoods. Truth may be unchanging, but the most probable scenario has to change as you obtain more evidence.

From the 1940s to around 1980, the globe actually cooled because of industrial aerosol emissions, which reflect solar energy back out into space. From around 1910 to around 1960, CO2 mediated warming was believed to be impossible because (a) atmospheric CO2 was mistakenly believed to be in a stable equilibrium with ocean dissolved CO2 and (b) CO2's emission spectrum was mistakenly believed to overlap that of water vapor, which is much, much more common.

In the 1950s both those beliefs were disproven, by Roger Revelle's study of ocean CO2 chemistry and by more precise spectrographic instrumentation. This meant CO2-mediated warming was physically possible, however in the 1960s cooling was still the consensus because at that time scientists thought aerosol cooling would outpace CO2 warming. That was easy to believe, because the Earth was cooling before our very eyes.

In the 1970s measurements of increasing CO2 along with newly available computer modeling techniques tipped the balance of scientific consensus toward warming in the upcoming decades even though we were still in a aerosol-mediated cooling phase.

This is about as robust as a scientific result gets: an accurate prediction of a reversal of current trends. Were the predictions being made perfectly precisely correct? Of course not. But on the whole the prediction of a reversal of current temperature trends was correct. There was still significant dissent about the direction of future climate in the 80s, but by 1990 it was clear to virtually everyone in the climate research field that CO2 warming was overwhelming aerosol cooling.

Again, that's how science works. It's about reasonable extrapolations from evidence, not eternal and unassailable truths.