The jury is the total community of the scientists who devoted their lives to learn as much as possible about the topics they judge.
If you ask "as a beginner" you should first learn about the
https://en.wikipedia.org/wiki/Greenhouse_effect
If it's too hard for you to grasp how it functions, imagine that you cover yourself with the invisible plastic bag. The bag won't produce any heat but it would prevent the heat from your body to dissipate as it would otherwise, effectively warming you up. The same way function the greenhauses. CO2 has that effect for Earth, known since 1824 and elaborated since.
I figure that there have to be 2-3 solid research papers on the subject.
https://en.m.wikipedia.org/wiki/Ice_core
The expected rise of CO2 closely matches our fosil fuels consumption.
https://www.skepticalscience.com/human-co2-smaller-than-natu...