Climate Change - Is There a Case for CO2 to Answer?
There is nothing in current global temperatures to indicate there is anything wrong. Despite substantial increases in atmospheric CO2, the current warming is not out of line with past climate cycles.
I have written several posts at www.awah.uk on aspects of the Climate Change narrative which is being sold assiduously, but with diminishing effect, by legacy or Mainstream Media (MSM). It’s a complex topic. It has many different aspects. It is clearly a narrative designed to divert resources – well over a trillion dollars of malinvestment - into unreliable and over-priced ‘renewable energy production. In the form of the Net Zero policy in Britain, it has played a big role in reducing the population’s standard of living. The electorate will probably destroy the Tory Party as payback.
One complexity is the difference between what might happen and whether and when it might be worth doing anything about it. Nobody is actually suggesting, with any scientific basis anyway, that the Earth will become seriously or significantly uninhabitable. Nor is there any support for the constantly repeated refrain that time is ‘running out’. The science in the UN IPCC reports themselves does not suggest this, or indeed provide many grounds for concern.
Finding the trillions needed to achieve the unfeasible Net Zero target would, however, wreck society. At least it would wreck the floundering and confused West. The Global South, comprising the other 7 billion inhabitants of Earth, is uninterested. They see it as a Western elitist scam.
A reasonable expectation, reflected in some climate models, might be that carbon dioxide (CO2) could cause a one or two degree increase in temperatures. Alarmists hate to admit it, but such a warmer world is generally agreed to be a more agreeable, productive and stable world.
Even if man-made CO2 emissions could raise temperatures by, say four or five, degrees, the costs of adapting locally would probably be smaller, and much further in the future, than those of panicky but lucrative (to the elites) net zero initiatives.
This time, I am returning to the Climate Change topic by reusing a modified version of a recent letter to a friend giving a different take on the controversy. It is that there is no ‘signal’, no unexpected or untoward change in temperatures, which would lead an impartial observer, if such there be, to suppose that there is a man-made global warming problem of any kind.
In my last post on Covid I discussed the idea that Covid had not really existed, at least as a potentially serious threat to the population. Once deaths caused by, in particular, the UK and US medical establishments are accounted for, there was little to write home about. This time I wonder about the ‘CO2 as a ‘Greenhouse Gas’ assumption. What’s the evidence for this?
Here is the modified text of my letter:
It does seem unfair of me not to engage with you about Climate Change, having suggested that I would. I take this opportunity to make amends. I propose to do so largely on the basis of my knowledge of archaeology and recent climate history - none of which is really controversial.
I would also draw your attention to several posts in my www.awah.uk blog on aspects of the Climate Change controversy, and to Bruges Group publications by Jeremy Nieboer laying out much of the scientific background. I would be happy to send them to you.
My case is that there is no case to answer concerning the likelihood that mankind is having any worrying influence on climate. We may well be putting more CO2 into the atmosphere. Atmospheric CO2 levels have risen from a little over 320 Parts Per Million to more like 450 PPM over the last 150 or so years, but this has had clear benefits in terms of greening the planet.
The Earth has been in an ‘Ice Age’ for two million years. This means It has had permanent ice caps at each pole. This is exceptional. Normally there have been no ice caps, and the Earth has been considerably warmer than it is now.
During these last two million years, freezing glaciations (what we used to call ice ages in school) lasting the better part of 100,000 year have alternated with warmer, briefer interglacial warmer periods lasting 10,000 to 20,000 years. We are roughly 10,000 years into the current interglacial. Within a few thousand years London will probably be tundra again.
Even now the Earth, in our current interglacial, is colder than it has been on average over the past few hundred million years. Atmospheric CO2 has been as much as ten times higher than it is now. Apart from the sea level presumably being 50 metres or so higher, allowing for water currently still trapped as ice, the pre-2 million BC Earth was in apparently excellent health and no danger. It was just a lot warmer, wetter, and fuller of life than it is now.
The climate history of the current interglacial appears to be that the first 5,000 years were appreciably warmer, say up to two degrees centigrade warmer, than the second half from 3,000BC onwards. A warmer world is indeed a wetter world. The Sahara was open Savanah or grass-land. It was a bit like the Serengeti, with lakes, rivers, teeming herds and sizeable human populations.
From around 3,000 BC the inhabitants of the Sahara, including the ancestors of the Egyptians and probably the Minoans, were pushed out of the developing desert as the world cooled somewhat.
Within the last, rather cooler 5,000 years we can discern three warmer periods - the Minoan, Roman and Middle Ages warm periods. These correspond to flourishing civilisations. In between them are cooler periods when temperatures fell by a degree or more. Such apparently modest falls made a big difference to human populations. They shortened crop growing seasons appreciably and made marginal environments uninhabitable. The most recent, 15th century to 18th century, cooling was the Maunder Minimum or Little Ice Age. Hence the paintings of the Thames icing over.
From some time in the nineteenth century, temperatures rose rapidly back towards the levels which were characteristic of previous ‘warm periods’. These levels had been largely achieved by the 1930s, which are still recorded in many places as having the highest temperatures of recent times. Temperature changes up to the early twentieth century must be natural. They cannot be the result of changing CO2 levels because atmospheric CO2 levels changed very little.
It was only after the warming trend had been largely completed by the 1930s, that atmospheric CO2 began to rise markedly to current levels of over 400 parts per million, whether caused by natural or manmade factors. This rise is not associated with a particularly clear trend in global temperatures, especially when measured by satellite.
Satellites remove an element of monkeying around with data from ground stations, and corrects for the Urban Heat Island effect which accidentally overstates ground station temperatures. There was, in fact, a slight cooling between the 1940s and the 1970s at the same time as global industrialisation proceeded apace. It also led to alarmism about global cooling, naturally.
It is likely that we have not reached the peak temperatures of the Medieval warming when the Vikings settled Iceland and Greenland. The Little Ice Age drove them out of Greenland, and nearly from Iceland too. When archaeologists excavate sites in Greenland, they find bodies buried in what is still permafrost. This indicates that temperatures were warmer then than they are now.
Similarly, glaciers retreating in the Alps and Norway have left uncovered previously unsuspected mountain passes which were used in the Roman and Medieval warm periods – as evidenced by abundant rubbish from those periods.
All we really have, outside the arcane realm of climate modelling, is a weak and possibly lagging correlation in the post-1850 period between atmospheric CO2 and global temperatures. Further back in time, there were hundreds of millions of years of negative correlations between the two.
Importantly, we just don’t see any patterns in the climate record of the past few millennia which cannot be explained by normal and natural cyclical change unaffected by human activities.
As with Covid, models based on unsubstantiated assumptions may have been used to create unjustified alarm, resulting in political and commercial gain for some, but loss for most. The key assumption in the models is that CO2 is a greenhouse gas. I have seen articles asserting that CO2 is not a greenhouse gas. I have not heard about laboratory experiments which demonstrate the existence of such a greenhouse effect. If you know of any please direct me to them.
Recorded atmospheric CO2 levels have apparently increased by around 50% since the mid twentieth century. If CO2 is such a significant greenhouse gas, why is the world still no warmer than it was during the Medieval Warm Period? One answer, by the way, is that even if CO2 is a greenhouse gas at lower levels of concentration in the atmosphere, further increases in atmospheric CO2 levels will have next to no warming effects. This is discussed in the Bruges Group publications mentioned above.
In any case, temperature data over past millennia and centuries do not suggest there are grounds for supposing increased levels of CO2 are having a significant warming effect. The current warming cycle is indistinguishable from past warming cycles.