The implication of global warming is that "every little bit counts." Not so. In nature, the prevailing influences will render most other influences irrelevant. All minor influences disappear in the background. The extremely small heat created by greenhouse gases is overwhelmed by larger influences and disappears in the background.

Most heat gets into the atmosphere through conduction, convection and evaporation. It doesn't matter how energy gets into the air, because the result is determined through equilibrium.

The most extreme example of miniscule effects being promoted is the claim that secondary effects are twice as large as the primary effect. In other words, global warming caused by carbon dioxide causes more water to evaporate into the air, and water vapor is a stronger greenhouse gas than CO2; so the increased water vapor does more heating than the direct effect of carbon dioxide.

This claim totally defies the fact that any secondary effect would be so miniscule that it would get overwhelmed by other influences. In fact, there is a tendency throughout physics to ignore, or be totally oblivious to, the infinite number of complicating influences that interact with each other in nature. Physicists analyze effects as stand-alone concepts uninfluenced by any complexities.

If the extremely minute influence of global warming upon water vapor were relevant, why were not such influences occurring in the past and resulting in total thermal runaway? It's preposterous to say secondary effects never existed until humans influenced global warming. What would a base-line be for an absence of secondary effects? There would be no such thing as an absence. The supposed flat handle on the hockey stick graph would always be increases due to secondary effects, if there were such a thing as secondary effects.

If there were such a thing as a straight line in nature, why would it have existed at just the level of CO2 and temperature that existed before humans influenced the result? There is no force in nature that determines what "just before human influence" would be.

Both the temperature of the globe and amount of CO2 in the air vary wildly throughout history. Why did not each increase result in a compounding effect causing thermal runaway? Only because secondary effects are absurd.