In this third essay I want to illuminate the several strands of the core argument behind the notion that global warming is dangerous for humanity, as well as threatening for other residents in the eco-system of the planet. In my first venture into the debate (A Cool Look…) I summarised the 2008 AGW proposition like this:
Human activity in burning coal and oil, and clearing forests has, over the past century, put an enormous amount of carbon dioxide into the atmosphere where it has combined with water vapour and other gases like methane to increase global temperatures in an unprecedented way. The evidence that this has occurred is clear-cut, and the increase in temperature will have, according to our computer models, dire effects on the planet, causing the melting of polar ice, the raising of sea levels, droughts, floods, storms and desertification. We must put an end to this prospect by changing our way of life lest catastrophe strike us. It may already be too late.
I accepted that what I put forward then was what you would read in the newspapers or see on television rather than cool scientific analysis — but the media inform us about the news. In fact, the Summary for Policymakers (SPM) of the Third Assessment Report (TAR), the one available to me then, says all of the above except my last sentence. That what we might be doing could be too late was an inference anyone could pick up from what some commentators were saying in the early noughties.
If we move to the most recent IPCC Report, AR5’s SPM in 2013, there is not much difference in the core message. There is now, however, an added note of extra confidence couched in apparently statistical terms. What was missing from my summary, as well as the IPCC SPMs, was why it was that warming was bad for us. I will deal with that question in a later summary, but for now it is probably enough to say that the Global Circulation Models (GCMs), on which accounts of future climates were and are based, predicted that warming would just increase and increase, eventually making the planet more or less uninhabitable. Indeed, there were some who said that the warming could not be taken out of the system for a very long time. Things could only get warmer, and warm was bad.
Actually, it is cold that is bad. We need warmth for the germination of the seeds that are the basis of our foods. Life loves warmth, and a warmer Earth should be better for most plants and animals. How much warmth? Ah, that is for a later essay, but it is worth noticing that in earlier eras life flourished at much higher average temperatures than exist today, and with much higher concentrations of carbon dioxide as well. And one could note that people live in the tropics perfectly happily. One of my colleagues suggests that one reason for the scare is that people in the temperate regions have no idea from their own experience of how it is that people can live with high average temperatures and high humidity — and flourish.
Three things about the AGW proposition made it, in my eyes, an inadequate basis for far-reaching public policy of a global nature, which is what was being urged at the time. The first was that to a reasonable eye, the temperature data, the data about precipitation, and the data about extreme weather events, about glaciers and ice-caps, were a mixture of recent reasonably accurate data, older and much less accurate data, anecdote and surmises from one or two cases. The second was that the climate botherers (I didn’t use that term then) spoke about these data as if they were all gold-standard, which they plainly weren’t. The third was that almost everything about the future was based on the projections of GCMs, which had been neither validated nor verified. All this was couched in what I called the almost panicky media mood about ‘global warming’, in which human beings are pictured and some see themselves as evil actors in the destruction of their own habitation (through greed, arrogance and lack of will), and who deserve the punishment that will be theirs. I saw no reason to think this way and, nearly a decade later, I am still astonished at how many quite sensible people believe in this stuff without examining it at all closely.
I thought it would be helpful to my audience in 2008 to dissect the statement above into a set of topics which I could then analyse, and I chose these ones:
- the extent to which the planet is warming;
- whether or not such warming is unprecedented;
- whether or not the warming is caused by our burning fossil fuels;
- the likelihood of polar ice melting in a major way;
- the use of computer models in predicting future climates;
- the reluctance to admit uncertainty; and
- the extent to which we need to change our way of life to avoid catastrophe.
These days I would need to add topics about alternative energy and its utility, the difference between climate and weather, the role of the media, and probably extreme weather and its connection, if any, with ‘climate change’.
In 2008 it was relatively easy to deal with each of these topics with a few examples. Now the direction of each topic is the same, but the arguments and their complexity are much more extensive. In 2008 the ‘hiatus’ was only a few years old, and no one was talking about it. Indeed, everything was building towards the momentous Conference that would take place in Copenhagen and bring ‘climate equilibrium’ back (yes, there was such a phrase). In 2016 there is just so much more to argue about. Which means that the science is even less settled than it was then.
I returned to my Planning Institute paper three years ago to see what had happened since, and you can read that here. Even earlier, I tried to do what I am now doing, and started it here, and followed it with a piece on measuring global temperature, and you read that one here. Then I stopped because other things arrived in the news, and I wrote on those — that is one of the real problems in trying to plan a website’s topics. But all being well, this time I’ll really finish it!
Next: Is the planet warming?
Footnote: So much of the talk about ‘climate change’ is deadly serious, but every now and again I come across something that makes me laugh, which does clear away for a moment the ideological cobwebs that festoon this issue. Here’s an example. It’s old, but it’s fun.
Join the discussion 15 Comments
Good, lucid discourse, Don, and you end splendidly with a cartoon I had not seen before. To your list of topics I’d be tempted to add a question configured around the social pathos that has accompanied the AGW panic, its kinship to other mass scares in human history, and the subversion it has done to the integrity of Science.
I would add examples of the failed, false and fallacious predictions which litter the CAGW scare. The latest being Al Góre’s declaring on 27th January 2006 we had a “planetary emergency” and we would be doomed within 10 years if we did not act. And ask the question how many failed, false and fallacious prediction are required before the climate botherers begin to realise that the CAGW hypothesis does not add up.
The previous Eemian interglacial was much warmer than our Holocene, with sea levels at least 5 metres higher and therefore more polar ice melt etc. So what happened to the poor polar bears I wonder? Well obviously they’re still here and their numbers have increased five fold since 1960.
Today we know that satellite data has shown no warming over Antarctica since 1979, so that stuffs up the theory of polar temp amplification.
Global SLR from NOAA tide gauges show about 1.5mm to 2 mm a year or about 200 mm max per century or about 8 inches. Just the same as the previous century. So where’s their CAGW impact? Of course NOAA now shows Sydney SLR at just 0.65mm year and Brisbane 0.09 mm a year or about 2.6 inches and 0.36 inches per century. Where’s the Co2 impact?
Remember SLs on our east coast were at least 1.5 metres higher at the end of the NATURAL Holocene climate optimum just 4,000 years ago. See Narabeen man ABC Catalyst.
We could go through so many of the CAGW icons and we find they are wrong. Droughts ( over OZ) were much worse in the past than today, see the recent Vance and Baker studies. Vance found many periods over the last 1,000 years that were the same as our worst droughts and the 12th century was much drier than anything we’ve experienced over the last 100 years. And Baker found many worse droughts over the last 500 years. Also the Calvo study found that temps had dropped over southern Australia and it has been drying out over the last 5,000 years.
Dr Goklany, Lomborg and Oxford Union studies show that death rates from extreme events have dropped by 97% since the 1920s. Once again where is the impact from more co2?
Polar bears. North Pole. Floating ice. Archimedes.
More idiotic nonsense from more of these silly donkeys. Climate change is causing animals to behave strangely in the UK. What next?
Don, in my view when you write a paragraph like this it places you on the very periphery of the debate.
” Actually, it is cold that is bad. We need warmth for the germination of the seeds that are the basis of our foods. Life loves warmth, and a warmer Earth should be better for most plants and animals. How much warmth? Ah, that is for a later essay, but it is worth noticing that in earlier eras life flourished at much higher average temperatures than exist today, and with much higher concentrations of carbon dioxide as well. And one could note that people live in the tropics perfectly happily. One of my colleagues suggests that one reason for the scare is that people in the temperate regions have no idea from their own experience of how it is that people can live with high average temperatures and high humidity — and flourish.”
“Peripheral” as is, not very influential. It is hard to imagine that a statement like
” And one could note that people live in the tropics perfectly happily.”
would have resonance with anyone who was remotely informed about AGW. The idiom “Jumping the shark” comes to mind.
You would be the shark then, or perhaps the troll.
Don, thanks for these essays, I”m enjoying them.
This comment caught my eye;
“Global Circulation Models (GCMs), on which accounts of future climates were and are based, predicted that warming would just increase and increase, eventually making the planet more or less uninhabitable. Indeed, there were some who said that the warming could not be taken out of the system for a very long time. Things could only get warmer, and warm was bad.”
I’m wondering if you have any thoughts or observations on the following aspect.
It is known that the greenhouse, heat accumulating properties of CO2 are logarithmic, not linear. A steep initial increase, the curve gradually flattening out once a certain level has been reached, eventually warming from CO2 alone, stops increasing.
I almost never see this mentioned.
As you commented there, the public view from proponents gives the implication, intended or not, it’s never ending – and certainly more linear than logarithmic. The shape of that sensitivity curve, if that’s the right term, and where we might actually be on it, never seems to be discussed. Are you aware of any research, or even opinion, on this aspect?
The short answer to your principal question, Wayne, is that the IPCC can pass by the logarithmic relationship because it is focussed on ‘climate sensitivity’. Yes, it accepts the logarithmic relationship but points out that whatever the increase it will be multiplied by ECS, conventionally 1.5 to 4.5. So a 1 degree C increase becomes 3 degrees C. You can see all this in an relier piece of mine at
which provides some other useful links. I am not a fan of ECS, as you will see from the essay.
The climate sensitivity curve is essentially a straight line for CO2 concentrations that span preindustrial times to double what they are now.
Here is a log function (see second graph)
And here is a graph of temperature increase over the last 100 years.
The rise in temperature over the last 100 years does not look like a simple log function Clearly other factors are at play. Eg. ECS
For a bit more climate change humour try this link which was posted recently at Climate Etc.
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