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World Climate Change
An overview of the findings from the exploration of the science of world climate history
A fascinating and hot (pun intended) topic, perhaps even red hot, is the matter of climate change, or human induced global warming, and of course the claims of the consequences of these trends and their attributed future consequences for human communities, civilisation, the fellow species with which we share the planet and even the planet itself.
These all being matters promoted in favour of drastic action to prevent the claimed future harms.
Like almost all topics of such note in the 21st century (and in the case of climate change, even the last decade of the 20th century) the whole topic has been subject to claim and counter-claim, repeatedly degenerating into argumentum ad hominem, rather than evidence led seeking of the best known facts and acknowledgement of the profound uncertainty in the evidence and the science associated with the behaviour of earth’s climate.
It is now well known and generally understood that the earth’s orbit is in a “goldilocks” zone from the sun and that the character of the planet and it’s atmosphere ensure habitability for the life forms we know to be present upon this planet.
In particular the major plank of the clamour is that CO2 emissions are The cause of The warming, which it is claimed result in ever more severe weather and greater destruction of habitats for both human and other species and will result in the extinction of at least human civilisation and possibly species on the planet.
Again it is well known chemically and physically that the major radiatively active gasses act as constrictors or limiters of the heat balance escape of infra red radiation from the earth back into space, having been energetically sent to the earth by the sun in the first place. This process helps to keep the atmospheric “goldilocks” state that all life enjoys, and does in fact directly result in the processes explained by the theory of evolution.
In contrast the claims about “climate change” seen in almost all media, promoted by activists, for and against the evidence, for and against climate change, and for and against it’s possible or impossible consequences are in fact almost all speculations and gross exaggerations on both sides of this deeply polarised topic.
Few of those in the media or activists for or against the arguments about claimed consequences actually have any knowledge of the best known evidence about the history of life on earth, the planet’s atmosphere and geology over the last several hundred million years, and even several billion years.
To inform myself on these topics I have spent several years investigating and researching the best known evidence around these facets of the topic and built a series of presentations documenting. in simple form. these best known facts available to us in the 21st century about this history of deep geological time of earth. The concept of deep geological time was beautifully encapsulated by John Playfair when accompanying James Hutton on their boat trip to Siccar Point in Berwickshire in 1788 when he said “The mind seemed to grow giddy by looking so far into the abyss of time.”
The results are fascinating and of course tell us that any warming and any levels of CO2 that we see in the last 150 years, even over 400 years, are certainly not geologically unprecedented.
Also the geological and paleontological records strongly support the robustness of life on earth in the face of vast upheavals in atmosphere, ocean and climate throughout the billions of years, as well as in land masses as a result of the movement of continents and the growth and subduction of earth’s crusts. The fossil and even DNA records attest to multiple extinctions and huge explosions of new life multiple times in the history of life on earth.
It seems only rational that in exploring these data it is essential to abandon the activist stances of hysterical panic and the see, hear and speak no evil “denial” in all real senses and instead calmly look at the evidence dispassionately to see what it tells us.
Sadly since the whole matter from the mouths of activists and much of the media now resembles a strange cult of some deity and profound hatred of humanity in many cases, I have instead explored the evidence myself to see what the best known facts suggest.
The obvious finding that again is well accepted is that the presence of liquid water in the oceans and rivers, water vapour, CO2, methane and oxygen in particular in the atmosphere are key components of the flourishing of all life on earth for at least 3.5 billion years.
It should be noted oxygen is thought to have not become abundant in the atmosphere until about 2 to 2.5 billion years ago, and itself caused a major extinction of earlier life forms that could not tolerate so much oxygen, that had itself resulted from it’s expulsion into the atmosphere over the previous hundreds of millions of years.
As such we must understand that liquid water, water vapour and CO2 (composed of Hydrogen, Oxygen and Carbon) are central sources of all life and are the basis of plant life on which almost all animal life tends to thrive. A key output from photo synthesis by plants are the carbohydrate sugars they develop to grow and the by-products of their life and death processes are free oxygen and methane released into the atmosphere.
Particularly notable is that CO2 and methane have been present in the atmosphere in much higher concentrations throughout most of the history of almost all life forms on earth. The current Quaternary period is in effect equivalent to CO2 desert conditions.
In addition most of the history of earth seems to have exhibited much higher average global temperatures than are measured at present and even projected and claimed into the future in connection with the estimated future concentrations of CO2 and possible future warming.
Notable in the geological and fossil records are the cycles of hot and cold prevailing global mean temperatures over detectable geological time, at least up to about 1 billion years ago, in which in general the cold periods remain of somewhat shorter duration than the much warmer periods.
Interestingly however the particularly cold period of what is known as the Cryogenian (Sturtian and Marinoan) some 750 million years ago is generally thought to be particularly severe and has popularly been dubbed the period of “snow-ball” earth (sometimes “slush-ball” earth). Another pair of less severe but still very cold glaciations are suggested in the geological record during the Ediacaran (Vendian) period perhaps some 590 to 600 million years ago, and another sometime during the Ordovcian into the Silurian periods some 450 million years ago. A particularly severe glaciation again is recorded throughout much the Permian period some 250 to 300 million years ago. A further less severe cooling appears to have taken place at the end of the late Triassic and early Jurassic some 180 million years ago.
A new cool glacial period is now well understood to have started about 30 to 35 million years ago when the southern polar regions and the Antarctic continent started to form glacial ice sheets. It took a further 20 million years or so before ice sheets started to form in northern polar regions eventually forming large and persistent glacial ice sheets for most the last 2½ to 3 million years over Greenland and the Arctic ocean.
It is the last 2.7 million years that geologists refer to as the Pleistocene ice-age, in which we are living.
In between these various cool and ice ages the majority of time (perhaps 70 to 80 percent of the last billion years) the global mean temperatures were much higher than present, and are calculated in fact to be higher than anything humans are experiencing at present, at least in global mean terms. Perhaps as much as 15 or more degrees Celsius warmer than at present, on average.
The causes of the over-arching cycles of warm and cool sequences of some 150 million years give or take 20 million years peak to peak are not fully understood, but may be cosmic in origin as our solar system orbits the centre of our galaxy, though again the explanation often given by some is of course CO2. Whilst this gas and it’s radiatively active fellows undoubtedly plays their part there are many instances where it’s role as a driver is very hard to justify from the evidence.
The last million or so years, when the historical records are very strong thanks to the ability of scientists to extract key chemicals from the polar ice, tells a particular story of alternating cycles of relatively moderately cool and very severe glacial cold over some 100 thousand or so years peak to peak. This is very well supported for the last 100 millions years also by the benthic cores drilled from the sea beds around the world thanks to such similar scientific and engineering advances these last few decades.
It is quite well known that the modern human era of our agricultural civilisation in fact thrives in a less cold phase of the latest cycle. This we have dubbed the Holocene. This is now accepted as the most recent inter-glacial epoch of many identified from the evidence describing the last million years.
The previous four inter-glacial periods (the Eemian peaking between 130 and 120 thousand years ago, La Bouchet peaking between 240 and 230 thousand years ago, the Purfleet peaking between 330 and 320 thousand years ago and the Hoxnian peaking perhaps between 420 and 400 thousand years ago) in fact all generally exhibit evidence of substantially greater warmth than today and in fact anything currently projected to the end of the 21st century even by IPCC assessment reports.
Whilst the geological evidence of climate change is hardly proof or otherwise of what may or may not await humanity, other life forms and the planet over the coming 70 to 80 years, it does force one to give some pause to any tendency to catastrophise the future and instead look more realistically at what is being claimed.
Even the principle IPCC Working Group 1 report of the science simply does not make any of the claims seen in the media or from the activists. Equally it gives no credence to those claiming there is no warming either.
Both approaches are patently unfounded, by any measure.
The question then remains what truly are the causes of short term changes, for example over the last century, the last several hundred thousand years, the last several tens of millions of years or even these detectable cycles of the last several hundreds of millions of years.
This science is not settled at all and many plausible theories are posited from multiple quarters including many from very well qualified scientists that suggest causes and feedbacks to both the shorter term to medium term cycles and changes in temperatures and CO2 in the geological record.
Most of the evidence tends to demonstrate many, many instances of non-correlation of temperature and CO2 and all too often counter correlation, none of which prove causation.
The recent ice core record (800 thousand years) in fact clearly shows CO2 mostly following the time correlated temperatures. Again the physics involved in this case is well known in which as temperatures warm the oceans then take several hundred years to degass some of their store of CO2 into the atmosphere, and when temperatures cool the opposite happens over a similar time span in which the oceans sequestrate some of the CO2 from the atmosphere.
Another reason to remain calm, balanced and evidence led and accept the reality of the profound uncertainties is that the actions proposed by governments and activists are almost certainly bound to be so damaging to peoples livelihoods and well-being that caution against action is far more to be advised than precipitate and unthinking action.
Again we cannot avoid seeing that the pursuit of the environmentalists “precautionary principle” from the most vitriolic activists and the indulgent politicians is leading to the acceptance of imbalance in assessing the best policies and possible courses of actions, in which “solutions” are demanded without consideration of the consequences.
As Thomas Sowell expressed the counter-balance to this tendency in humanity “There are no solutions. There are only trade-offs.” (A Conflict of Visions: Ideological Origins of Political Struggles).
We are unfortunately faced all too often with hopeless failures from governments, authorities and activists over the decades from which few seem to learn to calm down and consider as many options as possible.
I heartily recommend the following books for those of an open and inquiring mind, in which scientists explore the scientific literature in a scientific way to elicit some understanding of the evidence currently available:
· “Unsettled. What Climate Science tells us, what it doesn’t, and why it matters.” By Professor Steven. E. Koonin.
· “Climate of the Past, Present and Future, A Scientific Debate, 2nd edition” By Dr. Javier Vinós.
· “Solving the Climate Puzzle” By Dr. Javier Vinós.
I also heartily recommend the following TV/film/video presentations from the last two decades or so which rationally and dispassionately explain the best knowledge we have of these trends from the “abyss of time” to the present:
· “Earth Story. The Shaping of our World.” From the BBC (1998), presented by the late Professor Aubrey Manning.
· “The Birth of Britain. The story of how Britain exploded into life.” From Channel 4 and National Geographic (2010), presented by Tony Robinson.
· “How Earth made Us.” From the BBC (2010), presented by Professor Iain Stewart.
· “Men of Rock.” From the BBC (2010), presented by Professor Iain Stewart.
· “Rise of the Continents.” From the BBC (2013), presented by Professor Iain Stewart.
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