People keep calling CO₂ a pollutant. That is absurd:


CARBON DIOXIDE AND HUMAN HEALTH
By Nasif Nahle

Pollutants are dangerous compounds for living beings.

Like water, CO2 is vital for life on Earth; thus, CO2 is not a pollutant or contaminant.

The specific heat of CO2 is 850 J/Kg K, which means carbon dioxide is able to absorb, store and emit heat. However, we cannot take this property into account when considering if CO2 is a pollutant because Water has a specific heat of 1,996 J/kg K, which means it is more efficient than CO2 at absorbing, emitting and storing heat. Water, like CO2, is vital for living beings.

CO2 densities have increased to more than 4000 ppmv in some geological eras, for example, during the Permian Period. When CO in the terrestrial atmosphere has reached densities this high in the past, life flourished abundantly. Consequently, we cannot consider such a high concentration of atmospheric CO2 as "pollution".

CO2 is the basic nutrient for plants and other photosynthetic organisms. Plants form the base of every food chain. Thus, the greater the density of CO2 in a given environment, the greater will be the production of food for plants and of the animals that feed on them.

In recent times it has become fashionable to relate CO2 to global warming, but water in its liquid or gaseous phase absorbs, stores and emits heat 4 times (400%) more efficiently than CO2. If, therefore, by this property water is not considered a pollutant, CO2 then cannot be considered a pollutant either...

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