The American government and European governments are forcing obedience to the idea that human-caused emissions of carbon dioxide will lead to catastrophic global warming and must be eliminated.  This idea is entirely and unequivocally false. CO2  is not now and never will be a problem.

To see why this is so, it is necessary to understand:

1. the role of greenhouse gases[1] in enabling Earth to maintain just the right balance between incoming radiation[2] from the Sun and outgoing radiation from the Earth;
2. how a change in the atmospheric concentration of CO2 affects its ability to absorb radiation.

If there were no greenhouse gases (GHGs), much of the Sun’s radiation would return to space and the Earth would be way too cold for life. Because of greenhouse gases, however, there is a 30% reduction in the radiation of energy back to space so enough heat is retained to make life possible. Conversely, if Earth had no way of getting rid of heat from the Sun, it would become unbearably hot.

The Earth sheds heat by radiating  energy in the infrared (IR) wavelength range. This is the same range of wavelengths (the same range of wave frequency) that a CO2 molecule can absorb. The more IR radiation absorbed, the more heat is retained in the Earth’s atmosphere. It is no wonder then that people get alarmed when they are told that the amount of CO2 in the atmosphere might double. They reasonably assume that if the concentration of CO2 doubles, the heat retained by CO2 will double and Earth will “boil”. Fortunately, this assumption is not true.

Suppose that CO2 levels doubled from the current 440 parts per million (PPM). What would happen? Basically nothing. Doubling CO2 reduces the radiation of heat to space by only 1%.  This would increase temperature by slightly less than 1⁰ C. No one would notice the difference

Why can physicists who understand radiation transfer have confidence that this conclusion, derived from a model, is correct? The relationship between the radiation of heat from the Earth, measured in milliwatts per square meter, and wave frequency, measured in waves per centimeter, in the absence of greenhouse gases, is known for sure. The frequency at which GHGs absorb radiation is also known. With these inputs scientists can calculate what a curve on a graph showing wave frequency on the x axis and heat emission on the y axis should look like, given the Earth’s mix and concentration of GHGs. By comparing the modeled curve to what is observed, it can be determined whether the model is correct. It turns out that the match of model to observation is almost perfect. Therefore, model simulations to see what happens when a GHG concentration is changed can be viewed with confidence. The model’s result that a doubling of CO2 causes only a 1% increase in temperature is robust.

Why is it true that the relationship between CO2 levels and warming is not linear, i.e., warming doesn’t double with a doubling of CO2? As the concentration level rises, the fixed capacity of a single molecule to absorb heat gets used up. Saturation per molecule (reduction in radiation absorptive capacity) offsets the increase in the number of molecules. At the current concentration of 400ppm, the per molecule absorption of radiation is reduced by four orders of magnitude relative to absorptive capacity in a low-concentration, mostly transparent environment. The process works the same way and creates the same outcome for water vapor as well.

As a way of explaining the effect in physical terms we are all familiar with, physicist William Happer uses the analogy of painting a barn with two coats. Although the second coat doubles the amount of paint applied, it has a very slight effect on the color created by the first coat. The higher the concentration, the less will be the heat absorbed per molecule. The system is self-regulating; it is impossible for it to run away.

The history of the Earth’s climate provides compelling evidence in support of the conclusion that the concentration of CO2 in the atmosphere plays a negligible role in climate change, and is not now and never will be a problem. At the very most it induces a very mild warming. Over the past 600 million years, it usually has been colder when CO2 levels were higher and warmer when they were lower. Furthermore, an increase in CO2 tends to follow a warming trend. Something that follows something else can’t cause it. The main reason for this sequence apparently is that when the oceans, a huge storage sink for CO2, warm, the result is CO2 outgassing.

What do independent scientists, retained by  the government-sponsored Intergovernmental Panel on Climate Change (IPCC), say about the effect of greenhouse gases on climate change? Two quotes summarize  their conclusions:

• “No study to date has positively attributed all or part [of the climate warming observed ]to [manmade] causes”.
• “None of the studies cited … has shown clear evidence that we can attribute the observed [climate] changes to the specific cause of increases in greenhouse gases.”

What leading scientists consulted by the IPCC have said is in direct contradiction to the IPCC’s Summary for Policymakers, an advocacy document written to support what government officials want to hear.

In sum, what we have here with the climate alarmism narrative is government-driven, media-hyped nonsense. If not repudiated, the consequences for global freedom and prosperity will be dire.

[1] The primary greenhouse gases are water, CO2, methane, and nitrous oxide.

[2] Radiation is the flow of electromagnetic waves which carry energy. The waves vibrate at different frequencies along a spectrum. The lower the frequency, the longer the wavelength, and the lower the energy.