CO2 Emission: Are Climate Models Based on Erroneous Data?

Are CO2 emissions really responsible for climate change? Some scientists question this long-held belief, suggesting reverse causality. Check out this controversial perspective.

Are CO2 emissions really responsible for climate change?
Are CO2 emissions really responsible for climate change?

For decades, the scientific consensus has mainly attributed global warming to the increase in concentrations of carbon dioxide (CO2) in the atmosphere, due to human activities such as the use of fossil fuels.

However, a minority of scientists propose a radically different vision: what if the increase in atmospheric temperature was actually the cause of the increase in CO2 levels?

Disputed causality

According to recent studies, in particular those led by Demetris Koutsoyiannis and his colleagues, the relationship between temperature and CO2 could be bidirectional, or even reversed compared to what is commonly accepted.

Using advanced methods of stochastic analysis, these researchers suggest that temperature increases could precede and cause an increase in CO2 levels.

Evidence in favor of fossil fuels

However, many elements still support the dominant theory. The Global Carbon Project indicates that human activities, in particular the use of fossil fuels, emit about 40 billion tons of CO2 per year, of which 88% come from these fuels and 12% from land use changes.

In addition, analyses of the carbon isotopes present in the atmosphere reinforce the idea that excess CO2 comes mainly from fossil fuels. Since the industrial era, the decrease in the ratio of carbon-13 (13C) to carbon-12 (12C) in the atmosphere indicates that additional carbon comes from fossil, and not natural sources.

Natural systems absorb more than they emit

Another argument in favor of traditional theory is that natural systems absorb more CO2 than they emit. About 45% of human-made CO2 emissions remain in the atmosphere, while the rest is absorbed by terrestrial ecosystems and oceans.

This absorption by natural systems helps to mitigate the increase in atmospheric CO2.

Simple analogy: the bathtub

To better understand this dynamic, let's imagine a bathtub where water flows and empties at a balanced pace. Adding a small additional flow (human emissions) will gradually increase the water level over time, disrupting the balance.

Carbon cycle and human interference: analogy of the bathtub.
Carbon cycle and human interference: analogy of the bathtub.

Similarly, although human emissions are smaller compared to natural emissions, they disrupt the balance and increase atmospheric CO2 levels.

Historical variations and short-term fluctuations

It is true that historical climate changes sometimes show temperature increases preceding CO2 increases, often due to factors such as changes in Earth's orbit or volcanic activity. However, these conditions are not present today.

Short-term fluctuations in CO2 levels, influenced by phenomena such as El Niño, do not contradict the long-term trend caused by human emissions.

The majority of scientific evidence continues to maintain that CO2 emissions from human activities are the main driver of current climate change. Theories suggesting inverse causality are intriguing but fail to reverse the established consensus.

To effectively address climate change, it is crucial to understand and accept the roles of natural and anthropogenic emissions.

Any hypothesis deserves to be examined, but political and environmental decisions must be based on the most robust data and models available.

References: Koutsoyiannis, D., Onof, C., Kundzewicz, Z.W., & Christofides, A. (2023). On Hens, Eggs, Temperatures and CO2: Causal Links in Earth's Atmosphere. Sci, 5(35).