If you found an odd lump on your body one day, what would you do? You could see a licensed doctor, whose knowledge has been gained from mostly objective, clinically tested, and peer reviewed research. You could see an oil tycoon who has made millions by being a wise businessman. You could also just do nothing.
I'd go to the doctor, myself. Yes, there's probably a small percentage that are bad, so I'd probably ask a second, or even a third to see if I get a consistent answer. If I went to 100 doctors, and 97 of them said the same thing, I'd put my money there, simply because they have knowledge from looking at history. If not, I might as well believe the sun still revolves around the earth, and that if I walk too far, I might fall off the edge of the "world".
Or, if astronomers predicted a 97% chance that a meteorite would land in your town, would you take a day trip? Or stay at home? The trip is pretty cheap: drive/take a bus to family or friend in another state.
Yes, fixing CO2 emissions is much more expensive than a day trip; we can't do it all in one day. We can start though, and give future generations a little more time to figure out a good solution.