What ?
Wait....
You're telling me that we are going to revert geologically and atmospherically/climatologically, back to a previous state, because CO2 wasn't in the ground but in the air and so it will return??
Well as colorful as that is, it would show a cycle wouldn't it. And so far no one on the AGW side is willing to concede that there is a pattern so I don't think that's the case here..
Also, Co2 isn't just from the breakdown of bio-matter as we know it. it also comes from the earth itself volcanoes produce a great deal of it. No dead bio-matter needed, lots of things can produce it naturally with or without carbon-based life forms.
Here's what is indisputable. Carbon dioxide is a greenhouse gas. That means it's transmissivity is higher for the spectrum of radiant energy from the sun, than it is for the spectrum reflected back from earth. Energy is trapped on earth.
Fossil fuels are made from biological waste trapped under ground which is made from carbon dioxide.
We know during the years that fossil fuels were sequestered from the atmosphere that atmospheric CO2 concentrations predictably went down, and so did global average temperature. (The Carboniferous Period occurred from about 360 to 286 million years ago). Look at the graph that you referenced for that Period. Look at what happened to CO2 concentrations and global temps.
Cause and effect predictable from energy balance. Animal life could not flourish at the start of that period. It did after that period.
For the last 100 years we've been steadily returning to the CO2 concentrations of that period by releasing all of that sequestered greenhouse gas.
Now, we could do nothing and hope that something that we don't know about will save us from what we do know about. But, we know that we will run out of fossil fuels anyway.
So, despite what you wish, private industry is investing in sustainable energy, and the transportation industry is working hard on getting more good, and less waste out of each pound of greenhouse gas we dump into the atmosphere.
We already spend billions of dollars and thousands of lives every year recovering from AGW enhanced extreme weather.
It's pretty certain that the lowest cost path, based on what we know, goes through fixing, rather than ignoring, AGW.
I didn't have to go past the bolded second sentence in your post to know that your scientific information is somewhat lacking. But setting that aside, yes we do know that climate change appears to be cyclical both short term (within a 1000 year or so period) and long term in which we get into the mega millions and billions of years.
But the question has not been answered, to my satisfaction however, whether significant CO2 increases CAUSE global warming or whether they FOLLOW global warming. Strong cases are made for both points of view.
But you did hit one truth. It is likely that humankind will eventually use fossil fuels faster than they are created in the earth and will eventually have to utilize other forms of energy. I have absolutely complete faith in humankind to figure out how to harness and use new forms of energy by the time we will seriously need them.
But until that time, they are and will continue to be used. Modern humans, after all, are a natural result of evolutionary processes as much as any other living things on Earth are, and there is no reason to think human activity is not as natural as activity of any other living organisms. But since humans of all living organisms have the greater ability to intentionally adapt to changing conditions, why not encourage us to be the best we can be?
Time and again we are told that we cannot return to an earlier, more innocent time of human existence re our morals and values. Why should we believe it any more feasible to return to a more primitive way of life re our energy use? Most especially when it is those already doing a good job who are expected to make the greatest sacrifices while the biggest 'polluters' are given a pass?
I for one do not wish to hand over my liberties, choices, options, and opportunities to government entities who have given me no confidence they care about me in any way and their primary motive is to force my obedience and to possess my assets. And I am simply not willing to agree to consigning huge populations of people to more generations of crushing poverty because they are denied ability to exploit their resources as we have already done.
Monitor global warming yes. But we know from the scientific record that plants, animals, and people flourish much more in warmer climates than they do in cold ones. Let's focus on helping people ADAPT to climate change and exploit it rather than perpetuate the often self serving myth that we must change something that in all probability is unchangeable by us.
Let's start with basics. Fossil fuels were created only during the Carboniferous Period. They aren't being created any more. What we have is what we will have, less what we we use.
Every carbon atom in them is from carbon dioxide from the atmosphere, used during that Period, by life, mostly plants and algae, to build themselves. When they died, during that period all of that carbon was sequestered from the atmosphere and held underground, to be transformed from dead plants and algae, by heat and pressure, into fossil fuels.
As those fuels are oxidized, the vast majority of those same carbon atoms are turned into CO2 and re released back into the atmosphere, from wence they came, and resume their prior job of transmitting more solar spectrum radiation to earth, than they allow earth radiation spectrum back out into space, thus elevating the temperature of earth to something higher in order to maintain energy balance.
Are you following so far?