The effect of added CO2 in the atmosphere is unknown.
It is the cause of from zero to one hundred percent of the global warming since the 1970s.
No one knows the correct percentage.
Many people claim 100%.
Lab experiments with CO2 spectroscopy suggest CO2 should cause mild, harmless warming in the troposphere, by reducing Earth's ability to cool itself.
We have had mild harmless warming since the 1970s.
That may be evidence the lab experiments were right.
If you assume the lab experiments are right (without proof), then CO2 was the main cause of of the mild, harmless global warming since the 1970s.
That's not scary global warming -- that's pleasant global warming.
Unless you add an unproven, imaginary, and hard to believe, water vapor positive feedback theory.
Which magically triples the expected warming effects of CO2 alone, creating a 'CO2 is the devil in the sky' fairy tale.
If you consider one real effect of CO2 -- greening the Earth -- then adding CO2 by burning fossil fuels, when using modern pollution controls, is beneficial.
The IPCC originally wild guessed that more than 50% of the warming after 1950 was caused by man made greenhouse gases.
Then the IPCC started claiming, without proof, that after 4.5 billion years of only natural causes of climate change, causing huge changes of the climate, natural causes of climate change were now just "noise".
The right answer, which makes people uncomfortable, is that no one knows the actual effect of adding more CO2 to the atmosphere.
But about seven billion people living on our planet have had experience with some, or all, of the global warming since the 1970s, and it has been pleasant.
There is no logical reason to expect future global warming ( a "climate emergency"?) to be completely different from past global warming (a pleasant experience!).
The coming climate emergency is wild speculation.
We know that because 'CO2 is evil' believers refuse to debate their climate astrology (consistently inaccurate computer game predictions of more than double the global warming that actually happens).
Real science encourages debate.
Junk science avoids debate!