Huh? You talked about temperature rise and fall over millenia. I put up a graph that covered about 11,000 years. Temperature takes a rapid rise in the last 100 years as shown in the graph that I posted. Why are you talking about 30 years? That's what science deniers do. They cherry pick data after deciding what they want it to prove. I didn't do that. All the data is there.
All you said about CO2 is true. What you miss regarding CO2 is its heat trapping properties. When the sun strikes and warms the earth, the earth in turn emits infra red radiation. In absence of an atmosphere, that radiation leaves the earth with no warming effect. Earth's atmosphere contains heat absorbing materials like water vapor and CO2. Some of the infra red radiation emitted by the sun-warmed Earth is absorbed by these materials. The earth's surface is then warmed up this warmer layer of air -- the greenhouse effect. As you say, CO2 is heavier than most gasses in the atmosphere. This creates a signature "greenhouse" effect of much warmer air layer at ground level and much colder layer of air in higher elevations than without a green house gas effect. Climate scientists have been tracking air temperatures and confirmed that this is indeed happening.
We can't plant enough trees to absorb all the CO2 burned by today's generators and cars. We could if we drastically cut emissions. I mean really severely cut, not just stop using electric toothbrushes.
Did you know that science denial is a hugely profitable lobby funded by that very same money trail you mention?