Two thousand years ago, Plutarch posed the question that defines the dilemma of causality: which came first, the egg or the chicken? Over the centuries, the answers varied depending on who gave them: philosophers, priests, biologists, paleontologists, etc. In the case of individual events, the formulation of the answer must respect the temporal priority of the cause over the effect. The same requirement applies (with certain modifications) in the case of comparing deterministic or stochastic processes.

The first are processes whose results are completely determined by the initial conditions and rules of the system. This means that if the initial state of a deterministic process is known, its future state can be accurately predicted (the movement of the planets, the mechanism of the clock, the spread of fires, etc.). Their advantage lies in the complete predictability of playback results.

On the other hand, stochastic processes contain a certain element of risk. This means that even if you know the initial state of a stochastic process, you cannot accurately predict its future state. Instead, one can only predict the probability of various possible outcomes. Classic examples: the result of a coin/die toss, the price of a share in the stock market on a certain day, the weather forecast, etc. Their prevailing character is the inaccuracy of the offered forecasts.

The climate and its variations, synergistically interconnected in the individual evolutions of five subsystems – the lithosphere, hydrosphere, atmosphere, biosphere and cryosphere – belong to stochastic processes, for which the “egg or chicken” causal relationship takes the form: process X is a potential cause of process Y or vice versa.

The cause-and-effect relationship of the two best-studied climate processes – temperature changes T and concentrations of carbon dioxide CO₂– indicate growth as a reason T which leads to an increase in CO₂ for hundreds of thousands of years before the beginning of the industrial revolution (around 1850) (Fig. 1).

Fig. 1. Changes in the temperature anomaly in the area of ​​the South Pole (blue line) over the past 400,000 years, constructed on the basis of Antarctic ice cores. Carbon dioxide (orange line) is measured from air bubbles embedded in the ice. (from Dessler, 2022)[1]

A simple visual inspection shows that the concentration of CO is changing₂ emerge after temperature changes. Compliance with the condition imposed by the time priority requires the determination of the temperature rise T as a cause of increased CO₂. Similar measurements made on Greenland ice cores point to the same direction of causality: T → CO₂.

With the onset of the industrial revolution and the burning of fossil fuels, the paradigm that has developed over millennia has changed: humans are “poisoning” or “polluting” the atmosphere (one of the five climate subsystems) CO₂ anthropogenic, the increase of which causes an increase in temperature, that is, global warming. In short, the chicken-or-egg causality has been reversed over the past two centuries: CO₂ → T. This paradigm has dominated in recent decades the environmental policies of developed countries and is less or not dominant in countries with poor or developing economies, the majority in terms of population. Based on IPCC reports and most climate experts (97%, better yet 99.99%), hysteria has recently erupted over an existentialist, apocalyptic, “code red for humanity” climate crisis, “boiling oceans” of young people who don’t want to have children , other young people who destroy works of art and do many other things, etc. The climatic “salt shaker” barely holds on to the CO stack₂ and if a cat comes up to tear it down, we’re done for.

Much of the story has its source in the remarks made by Carl Sagan in the motto of the article, and in a number of recent scientific developments that question modern causality, CO.₂ →T : It’s still a one-sided chicken-or-egg relationship, but it’s the opposite of what has been assumed for the past 200 years. These developments of scientific thought without ideological corsets include, among others:

– The first study published in 1990 in naturally and which initiated the current paradigm shift, clearly states:

The hypothesis that the increase in the content of carbon dioxide in the atmosphere is related to the observed climate changes is tested using modern methods of time series analysis. The results confirm that the global average temperature is increasing and that temperature and atmospheric carbon dioxide have been significantly correlated over the past thirty years. Changes in carbon dioxide content lag behind temperature changes by five months.[2] [s.m]

– A study that looked at temperature and CO data₂ and demonstrated that variations of CO₂ it follows after temperature fluctuations T → CO₂;[3]

– A study (in two parts) that created an extended theoretical framework for testing causality based on a stochastic assessment of the potential causal relationship between two processes using the notion of an impulse response function;[4]

– A study published last month that provides a practical application of an advanced theoretical framework using “hard” CO concentration data₂ and temperature fluctuations (“hard” data in this context means official data used by the authors of IPCC reports and other documents. In other words, the client’s “material” was worked with). The title of the latter study also inspired this article.[5]

The mathematical apparatus and many of the figures created in the mentioned studies have a high degree of complexity, unsuitable for a more informative than formative platform. Therefore, I suggest that interested readers familiarize themselves with the mentioned literature, which is freely available. I prefer to quote the main findings of the group led by hydrology professor Demetris Koutsoyanis:

Analysis of correlation gaps of two values, T and CO₂the study argues that although both directions of causality exist, the results support the hypothesis that the dominant direction of causality is T is Co.₂. Variations of CO₂ it follows temperature fluctuations with a lag of about six months on a monthly scale or about a year on an annual scale. The researchers then tried to interpret this mechanism in terms of biochemical reactions, as higher temperatures increase soil respiration and therefore CO emissions₂.

Of course, the results [. . .] assumes a potentially causal (unidirectional) system with T as cause and CO₂ as an effect Hence, it is widely believed that an increase in CO₂ the cause of the increase in T can be ruled out because it violates a necessary condition for this direction of causality.

[. . .] in other words, it was the increase in temperature that caused the CO concentration to increase₂.

Although this conclusion may seem contradictory at first glance, because contrary to popular belief [. . .], actually smart. The rise in temperature began at the end of the Little Ice Age, i.e. at the beginning of the 19th century, when CO emissions₂ were insignificant [. . .].

The main hypothesis of the causality direction of CO₂ is T is compelling because it all comes down to one cause – human CO2 emissions₂. Indeed, this story has been popular for decades. However, popularity does not necessarily mean correctness, and here we have presented strong arguments against this assumption.

Since we identified atmospheric temperature as the cause and CO₂ atmosphere as an effect, we may be tempted to ask: What is the cause of the modern rise in temperature? It is probably much more difficult to answer this question, since we can no longer attribute everything to one agent.

We do not pretend to answer this question, the study of which goes far beyond the scope of the article. We also do not believe that mainstream climate theory, which focuses on human CO2 emissions₂ as the primary cause, and considers the rest to be feedback from the single primary cause, can explain what happened on Earth during the 4.5 billion years of climate change.

If not from humans, where is the increase in CO coming from₂?

In addition to the argument of ignorance, there is an argument of causation that simply cannot be ignored:

Variations of CO₂ they appear after temperature fluctuations on all time scales that we can measure.

If you do not object to this, then it should be understood that CO₂ it Feedbacknot alone forcing temperature If previous warm periods showed a corresponding increase in CO₂then the same question must be asked: “Where did SO come from and where did it go?₂?”.

About the current carbon budget in the form of CO₂ in the atmosphere, simulations have been carried out and numerous studies have been written. Koutsoyanis et al. (2023) provide a balance of sources and sinks of CO emissions₂ again using “client material” –

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