Sunday, 9 August 2020

Why I love Skeptical Science

Here's their supposed debunk:

Climate Myth: CO2 lags temperature

"An article in Science magazine illustrated that a rise in carbon dioxide did not precede a rise in temperatures, but actually lagged behind temperature rises by 200 to 1000 years. A rise in carbon dioxide levels could not have caused a rise in temperature if it followed the temperature." (Joe Barton, US House of Representatives (Texas) 1985-2019"

What the science says:

CO2 didn't initiate warming from past ice ages but it did amplify the warming. In fact, about 90% of the global warming followed the CO2 increase.

The article is the usual contortions, they discuss cause and effect in a circular sort of fashion, convincing nobody but their Disciples.

But to really shoot themselves in the foot, they include this chart. Click to enlarge:

That shows a clear correlation between temperature and CO2 levels, doesn't it?

Historically, yes. But actually... NO!

Look at the right and left hand scales. In case it's not obvious, I have cut and pasted the chart into Excel, extended the scales, and extended the blue CO2 line to indicate current CO2 levels.

(The current high CO2 levels are almost certainly due to us burning fossil fuels over the last two centuries, so we can rule out current levels as being caused by higher temperatures, whether or not that was true in the past.)

Handily, this extrapolation also rules out CO2 as a cause of higher temperatures, or else current temperatures would (or will) be about 18 degrees hotter than they are now. In which case humanity would (or will be) pretty much buggered and we might as well throw in the towel. Click to enlarge:

Sometimes I wonder whether Skeptical Science isn't actually a sophisticated Big Oil-funded counter-propaganda exercise?

Taken at face value, Skeptical Science is an endless series of appallingly cack-handed own goals and unforced errors, all in apparent sincerity.

Proper Alarmists would have left off the left hand scale on the first chart and then included a "close up" chart of CO2 vs temperature for the last century as well, which would also show a very close correlation and quite possibly have fooled a lot of people.

You'd have to look closely to spot that in the first chart 80 ppm = 9 degrees (and 0 degrees is set at 260 ppm); and in the second chart 80 ppm = 0.8 degrees (and 0 degrees is set at 340 ppm), i.e. if second chart is correct, temperatures would be about 0.2 degrees warmer than they are now (which I am sure we can cope with).

I thought that the "science was settled"? So can they not tell us whether temperatures will be 18 degrees higher or 0.2 degrees higher? That's out by a factor of a hundred.


Sobers said...

I can never understand how anyone can look at the the official chart of temperature anomalies (your 3rd chart) and not ask themselves 'If the temperature rose by about 0.6C from 1910 to 1940, and the rise in CO2 only kicked off post WW2, how come the rise of 0.6C from 1975 to 2000 has got to be down to the CO2?'

Mark Wadsworth said...

S, nobody says there is an exact one-to-one link between CO2 and temp, so let's gloss over that.

You are right though, in terms of propaganda appeal, doing a chart from 1960 onwards would have been the most convincing.

Robin Smith said...

Have you seen the work of Dr. Rupert Sheldrake on skeptical scientists defending the indefensible?

Stephen Stretton said...

Hi Mark,

Thanks for posting this. This was a very important graph, and I dealt with it in depth when I used to give talks about climate 10 years ago.

The key thing to understand in relation to this graph, is that it's a complex system: CO2 affects Temperature, and Temperature affects CO2, and over different time scales. The causation is different between the two graphs.

Over the integlacial period, the 'temperature' side was the core driver ie Temperature -> CO2 -> Temperature etc
In the current period, the causation is CO2 -> Temperature.

I could explain in a bit more detail but that would take me away from what I want to do today. Have fun! Keep thinking and having fun.


Robin Smith said...

Steve, why not charge for your services as you offered to me when I asked you to furnish your evidence?

This is what climate scientists do