Human emissions of CO2 do not increase the concentration of CO2 in air except momentarily, locally. Any increase in concentration of a trace gas in air is offset by an equal increase in solubility of that trace gas by all liquids in contact with that gas. Any decrease in concentration of a trace gas in air is offset by an equal decrease in solubility of that trace gas by all liquids in contact with that gas.

Ocean surface, about 71% of Earth’s surface, is the largest absorber and emitter of trace gases like CO2. When ocean surface warms it emits relatively more CO2 than it absorbs per unit of time. When it cools it absorbs relatively more than it emits per unit of time. Emission and absorption of trace gases by liquids occurs continuously and simultaneously; the ratio is a function of temperature of the surface.

A trace gas is defined as less than 1%. Today, CO2 concentration in air is only about 0.04%. Millions of years ago, CO2 concentration was 0.6% and life was abundant, and as low as 0.018% and life was near extinction in an ice age. Other trace gases in air (for example methane, nitrous oxide, etc.) are far lower concentration than CO2. CO2 has been very slowly increasing (~2.5 ppm/yr) mostly because temperature of ocean surface has been slowly increasing due to various circumstances, but the amount of human-produced CO2 is not one of those circumstances. The Ocean is a huge sink or repository for CO2.

The amount of human-produced CO2 from all sources which is emitted to air is too small to be measured with acceptable accuracy and precision against ~160 times larger background CO2 flux being absorbed and emitted into and out of the environment.

This science is known as Henry’s Law.

Other posts on this blog about Henry’s Law:

And there are many more posts on this subject on my blog. Search on Henry, Henry’s Law, or CO2.