The science is clear and undeniable. It's simple physics. CO2 traps heat.

https://climate.nasa.gov/system/charts/15_co2_left_061720.gi...

If you can look at this chart and not understand why man-made climate change is a real phenomenon I'm not sure what to say.

FUD about whether some scientist 40 years ago understood this or not is completely irrelevant. You don't need to "trust" anyone to understand this. It's incredibly simple.