Climate Alarmism

Both images are sized at exactly 1000x1000 pixel or one million in total. In the upper one are 280 white pixel and in the lower one 410.

This accurately represents the concentration change of pre-industrial CO2 to current levels, but still doesn't indicate the potential greenhouse effect.
Both Mars and Venus atmoshphere is almost exclusively CO2 at around 96%. They would look the same in our example. However Venus surface temperature is on average 464°C and Mars is only -63°C. Earths 15°C is far closer to Mars than Venus even though it's CO2 concentration is only 0.04%.

What matters is not the concentration in percent, but the amount of CO2 over a square meter of a planets surface.

On Venus there is 1,006,956 kg/m2 of CO2. (4.63E20 kg / 4.6E8 km2)
On Earth there is 4 kg/m2 of CO2. (4.63E20 kg / 4.6E8 km2)
On Mars there is 165 kg/m2 of CO2. (4.63E20 kg / 4.6E8 km2)

Even with a 39.8 times higher CO2 density Mars is still bitterly cold. Venus on the other hand is super hot with 243,000 times the CO2 of Earth. In the purely mathematical scenario where we never run out of fossil fuels (or free oxygen) and burn them at the current rate it would take 90 million years to reach Venus levels of CO2. (CO2 absorbtion by plantlife is also considered constant )

sources: https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html
https://en.wikipedia.org/wiki/Atmosphere_of_Venus
https://en.wikipedia.org/wiki/Atmosphere_of_Earth