I believe it is short sighted for anyone to believe that we as a planet can stop in a year or even 20 years what it took the last 100 years to start.
We need to accept the consequences of what will happen. Start Planning. We need better predictions 10+ years out so that we can be ahead of the tragedies, to minimize suffering. There will be suffering. Anyone who thinks we can prevent it all probably also thinks we can feed all the children in Africa for a dollar a week. People in poorer countries at sea level will bear the brunt. Richer countries with berms in place already or plans to build them will do better. Oceanfront property would be a good market to exit at some point.
Denial is a political game. You can get more votes if you are on the side that people want to believe, even if it isn't the truth. Isn't democracy grand? This is why the Supreme Court, Court of Appeals, and District Court Judges are appointed, not elected. Cronyism is a problem, but that is another subject.
The effects took a long time to show up, so we didn't get the immediate negative feedback on our activities. As such, it is beyond the timescale that our instinctual human minds use to learn what is good and bad. We can learn from something we did 1 week ago, 1 month ago, or even 1 year ago if it comes back to bite us. One decade is pushing it. I believe that is why people have such a hard time accepting responsibility.
100 years ago we had just invented cars! Cars are great. Lets all get big cars with powerful engines so we can go fast.