Saturday 11 December 2021

"How do we know more CO2 is causing warming?" Part 2

Easy, just take it as a given.

The British Antarctic Survey, who really ought to know better, have come up with this piece of nonsense:

It is often said that the temperature ‘leads’ the CO2 during the warming out of a glacial period. On the most recent records, there is a hint that the temperature started to rise slightly (at most a few tenths of a degree) before the CO2, as expected if changes in Earth’s orbit cause an initial small warming.

But for most of the 6,000-year long ‘transition’, Antarctic temperature and CO2 rose together, consistent with the role of CO2 as an important amplifier of climate change (see Fig. 4 overleaf).

In our modern era, of course, it is human emissions of CO2 that are expected to kick-start the sequence of events. We see no examples in the ice core record of a major increase in CO2 that was not accompanied by an increase in temperature.


If we look at Fig 4: we can also see that the converse could be true, as they start to imply, then rapidly back-pedal from, presumably before they are hauled up in front of the Inquisition for heresy. They then go on to state a fairly conclusive proof why CO2 isn't causing warming, presenting it as proof of the opposite.

From the air in our oldest Antarctic ice core, we can see that CO2 changed in a remarkably similar way to Antarctic climate, with low concentrations during cold times, and high concentrations during warm periods (see Fig. 3 overleaf). This is entirely consistent with the idea that temperature and CO2 are intimately linked, and each acts to amplify changes in the other (what we call a positive feedback).

Well, no, if it was positive feedback, the warming would release more CO2, which would cause more warming, which would release more CO2, which would cause more warming and so on, until the seas boiled away into space. This they haven't done, from which we conclude that a rise in CO2 levels cannot both cause warming and be caused by it. Since no-one seems to dispute the latter, then the conclusion about the former is obvious.

6 comments:

Mark Wadsworth said...

What sort of insane vertical scale have they applied to the lower part of the chart? They are just making up stuff.

Al Gore's long term chart shows a distinct correlation, plus 100 ppm CO2 = plus 10 degrees C.

The Warmenists' short term chart show a distinct correlation, plus 100 ppm C02 = plus 1 degree C.

So what does plus 100 ppm mean? Plus 10 C or plus 1 C?

Mark Wadsworth said...

In response to your last sentence, it's pretty clear that the latter - warming oceans release more CO2 - is true. Therefore the former - CO2 causes warming - cannot be true (which we have established independently).

Bayard said...

Sorry, got it the wrong way round, now corrected.

Mark Wadsworth said...

B, ta.

You make a good argument, but they firmly believe at there IS positive feedback (not sure why or based on what evidence, but belief is belief), and your logic is based on the fact that there clearly isn't any and never has been.

Bayard said...

Roman Catholicism was once defined as "believing six impossible things before breakfast", which itself is a quote from Alice in Wonderland, but all belief systems, including Alarmism, require a certain suspension of the critical faculties.

Mark Wadsworth said...

B, having now read the original thing, those two lines show concentration of CO2 and concentration of deuterium (hydrogen with an extra neutron).

They correlate very well. We assume, probably correctly, that higher levels of either gas correlates with warmer periods. That's about all we can take away from that.

Based on that info alone, it's just as likely that deuterium causes global warming as CO2 does.