The butcher, the baker, and the candlestick maker are all talking about Net Zero.

This condition exists when all the carbon emissions emitted into the Earth’s atmosphere balance the carbon emissions taken from the Earth’s atmosphere; a presumed idyllic condition that does not exist today.

It is argued that the carbon emissions from man’s use of fossils fuels in the last two hundred years has so disrupted a presumed recent historic net zero balance in the Earth’s atmosphere that excess carbon emissions will now cause catastrophic global warming.

The logic of this position calls for the banning of fossil fuels and the restoration of policies that will achieve net zero and ensure humanity’s survival.

Surely before accepting the above argument and promoting Net Zero policies, three critical questions need to be answered. Firstly, is there a credible link between the rise in greenhouse gas emissions from the burning of fossil fuels and modern global warming? Secondly, is there a limit to the warming effect of an increase in atmospheric greenhouse gases, particularly carbon dioxide? Thirdly, are there any benefits from an increase in greenhouse gas emissions that may outweigh any curtailment in those emissions?

On the first question, it is easy to argue that there is no credible link between the rise in greenhouse gases and the global warming that has occurred since the middle of the 19th Century.

Such a statement may seem a shock to many, but there were at least 70 years of temperature pauses in the past 150 years while carbon dioxide levels increased without any global warming. For example, between 1945 and 1975, carbon dioxide levels rose strongly, and yet global temperatures paused for 30 years.

The CIA even warned the American President of an impending ice age.

There is a further anomaly. Why is there no change in the rate of a global warming when carbon dioxide levels change? For example, the rate of warming remained unchanged at around 0.16°C per decade while past carbon dioxide concentrations tabled by NASA rose: 4 parts per million between 1860 and 1880; 8 parts per million between 1920 and 1940; around 38 parts per million between 1975 and 2000. But, if carbon dioxide levels determine the rate of warming, how could the rate of warming be the same in periods with different rates of change in carbon dioxide levels? Such an anomaly suggests that there are more important factors in the climate system that far outweigh any climate effects due to changes in greenhouse gas levels.

Regarding the second question, the net zero argument presumes that the rise in greenhouse gas concentrations in the atmosphere will lead to catastrophic global warming, if unchecked.

This presumption is false.

The warming effect of carbon dioxide is limited as that gas can only absorb certain infrared wavelengths emitted by the Earth’s surface; wavelengths around 15 microns. This wavelength represents a very narrow section of the infra-red spectrum emitted by the Earth’s surface; a spectrum with wavelengths ranging from 4 to 70 microns. Consequently, once infrared radiation of 15 microns is absorbed by atmospheric carbon dioxide, there is no other bands of infrared radiation that carbon dioxide gas can absorb.

Indeed, there is geological evidence that extremely high carbon dioxide levels, well above today’s level of 430 parts per million, will not lead to hothouse conditions. For example, there was an ice age, not a hothouse, when atmospheric carbon dioxide levels reached 4,000 parts per million 445 million years ago in the Ordovician Period.

There was also no catastrophic global warming for over 55 million years when carbon dioxide levels were around 2,000 parts per million during the Jurassic Period. Such historic events dispel any idea that very high greenhouse levels lead to hothouse conditions.

Finally, with regard to the third question, there are other effects linked to carbon emissions that need to be considered.

With regard to toxicity, carbon dioxide levels above the current 430 parts per million pose no danger to human life. In submarines carbon dioxide levels of 3,000-4,000 part per million are normal and those levels can safely rise to 6,000 parts per million.

And about plant growth, plants benefit from high carbon dioxide concentrations. Plant species are subdivided as either C3 or C4 plants because there are two different photosynthesis pathways in the plant kingdom. In high carbon dioxide concentrations, all C3 and C4 plant types need fewer pores on the under-leaf to exchange gases with the atmosphere. Since such pores also exchange water vapour with the atmosphere, all C3 plants (e.g. wheat, rice, and soyabeans) and C4 plants (e.g. maize, sugar cane, and sorghum) transpire less water and become more drought tolerant in high carbon dioxide concentrations. In addition, the C3 plants, enjoy much higher growth rates in high carbon dioxide concentrations. Such high growth rates also occur in modern greenhouses where carbon dioxide levels are maintained around twice present levels ~ 800 to 1,000 parts per million.

There is abundant evidence that the effect of higher carbon dioxide levels has benefited vegetation worldwide since the mid 19th Century. Scientists now talk about the Greening of the Earth and assert that further increases in carbon dioxide levels will be even more beneficial to agriculture production.

For example, the Australian CSIRO has shown an 11 per cent increase in foliage cover occurred in arid areas of Australia, North America, the Middle East and Africa between 1982 and 2010. Such an improvement in foliage indicates that crop production also increased; a real benefit during a period when world population grew from 4.2 billion to 7 billion. Such evidence suggests that the Earth’s food production will continue to benefit from further rises in carbon dioxide levels. But as the world’s population continues to increase food production will stall if Net Zero policies are implemented.

In conclusion, Net Zero policies should be abandoned completely as those policies are based on bad science. Net Zero policies cannot alter climate change. Net Zero policies will have restrictive effects on world agriculture. Net Zero policies will further undermine the economy of those countries where their internal policies have led to an over-reliance on intermittent renewable energy for electricity production.

Unfortunately, there are politicians trying to appease the proponents of Net Zero policies by pushing for longer timelines for these goals to be achieved. Such politicians think any argument to drop Net Zero quickly will result in their political death, so they muddy the water by promoting longer timelines for green goals.

Such arguments only support the efforts of the Net Zero protagonists to rapidly curtail the use of fossil fuels and further damage modern industrial economies. These politicians are the enemies of future generations as they only consider their short-term political aims. They take neutral vague positions because they do not think that the man-in-the-street has the intelligence to understand sound arguments against Net Zero policies. They fail to realise that the man-in-the-street will respond to political argument against Net Zero policies, but only when such argument is proposed by politicians with strong convictions.

Howard Thomas Brady is a member of the Explorers Club of New York, the Heartland Institute (USA), and the CO2 Coalition (USA). He is the author of two books: Mirrors and Mazes: A Guide Through the Climate Debate and Letters from Hurrell Street.