[nemo44x]

The fact you don’t even understand this basic fact and yet are so certain should concern you.

1. Logarithmic effect of CO₂ • The warming effect of carbon dioxide grows logarithmically with concentration, not linearly. • This means the first 100 ppm of CO₂ caused a much larger temperature impact than, say, an increase from 400 → 500 ppm. • Each additional molecule of CO₂ contributes less extra warming because much of the infrared spectrum it absorbs is already saturated.

2. Geometry of “forcing” • Scientists describe this as radiative forcing, measured in watts per square meter. • Roughly, each doubling of CO₂ concentration produces about +3.7 W/m² of forcing, which translates (with climate sensitivity) to ~1.5–4.5°C warming. • So it takes geometrically more CO₂ to achieve each additional degree of warming. For example: • Going from 280 → 400 ppm may give ~1°C warming. • Going from 400 → 560 ppm (another 160 ppm) gives another ~1°C. • Going from 560 → 840 ppm (280 ppm more) gives another ~1°C. • And so on — the increments needed get larger each time.

[jaybrendansmith]

This is a bit better. You are saying it IS happening, but just not gonna be that bad. I sure hope that's correct, but don't you think 1000s of climate scientists have taken this simple fact as a consideration in their analysis? Even if the effect is logarithmic, we are now at 420 CO2, well above preindustrial 280. We’ve already added 1.2 degrees of global warming. Continuing on the current trajectory will push us to 560 or higher within this century for multiple additional degrees C of warming. The fact that each extra ppm does a bit less does not mean the danger goes away, it means you need bigger increments of CO2 to get the same forcing, and presently we are adding those big increments very quickly. Climate scientists already use the logarithmic law of CO2 and the forcing geometry in all their calculations.