You'll never convince those who practice confirmation bias.
My personal belief is that the CO2 forcing in models is overstated by 1/3 in an effort to blame CO2, and allow for government control of CO2 to raise revenue. Why would persons in the government act in this manner? The answer is obvious to anyone with an ounce of experience with either people or business. Any item that can be regulated and used to generate revenue is seen as a good thing to our dear government class. They threaten the cutting of vital services and never trim any uneeded projects. Instead they cry for their own, the poor overpaid government worker.
Global warming, climate change, or whatever you call it next, is the ultimate revenue machine for the government class. If you require your information to have their seal of approval, you limit the depth of your knowledge and leave them with the total control of your paradigm. As we've seen from the last few months, the science is far from the best.
But, dear warmers, you must keep your faith. You'll make for such rich comedy in the future.