I am aware of this. As the concentration of CO2 increases, the incremental warming effect decreases. The first 20 ppm has an incredibly dramatic global impact. Every 20 ppm incremental increase after that decreases.
It is true that any addition will have some impact, but the incremental impact of 20 ppm today is just about unnoticeable. Every molecule of CO2 does prevent some heat from escaping into space.
Climate experts compare this to painting a window to keep light from escaping out of a room. The first coat of paint had a pretty dramatic effect.
Every succeeding coat of paint has a vastly reduced impact. Incremental increases at this point really have a very diminished impact.
Before the amount of CO2 has risen to the point at which we are "cooked", we will have asphyxiated. You can relax.
The Diminishing Effect of increasing concentrations of atmospheric CO2 on Temperature | edmhdotme
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[FONT="]The logarithmic diminution effect is an inconvenient fact for Global Warming advocates and Climate Alarmists. It is nonetheless well understood within the climate science community. But the effect is not much discussed nor ever emphasised.[/FONT]
[FONT="]An illustration of the CO2 diminution effect with increasing concentrations, can be imagined as if one was painting over a window with successive layers of white paint. The first layer will still be translucent, subsequent layers will progressively reduce the translucency until the window is fully obscured and thereafter further paint layers can make no further difference to the fact that the window is already fully obscured.[/FONT]
[FONT="]Similarly extra concentrations of atmospheric CO2 have ever diminishing effects on temperature, until at about 1000 ppmv they become totally negligible.[/FONT]
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The logarithmic diminution effect is the likely reason there was no runaway greenhouse warming caused by CO2 in earlier eons when CO2 levels were known to be at levels of several thousand parts per million by volume, (ppmv).
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