The SEQUESTRATION of CO2 or a FERMI PARADOX FILTER?
Updated: May 19
In about 4.5 Billion years he sun will go nova and expand into a Red Giant and swallow the earth. There will be no life on Earth, at least no life as we know it long before this happens.
About 750 million years ago the earth went through two Snowball Earth periods which were controlled by the interplay between the earth releasing greenhouse gases into the atmosphere and then the development of life that used up those greenhouse gases faster than they were being produced forcing us into another Snowball Earth. During this second snowball Earth life forms developed which used oxygen instead of the greenhouse gases and the winner finally being the ones that gobbled up oxygen instead of those greenhouse gases. In other words there was finally a balance between those lifeforms that used greenhouse gases to produce non-greenhouse gases and lifeforms that used the non- greenhouse gases to produce greenhouse gases allowed the earth to stay warm for a long enough period for other forms of life to flourish and evolve. This all happened from about 750 million years ago until right at 600 million years ago.
So life in the form that evolves into humans has been on earth consistently for only around 600 million years of the suns last 4.5 billion years. And this was brought about only because life forms happened to evolve that used oxygen to survive in balance with life forms that use greenhouse gases to survive. If those oxygen using life forms had not accidentally evolved the earth would have been stuck in a never ending cycle of snowball/warm/snowball . . .. One may well need to consider this balance as critical to the survival of intelligent life, and over the last 50 million years mammals are contributing to the depletion of the 02 component of keeping our species alive.
It seems that in the big picture we are almost at the end of the life of our kind here on earth. It is indeed a bit ironic that life with enough intelligence to maybe do something about the end of its own kind of life has chosen the route of the heard to bring about their own kinds demise. But don’t get overly worried, even though health regulations say we should stay above 19.5% oxygen the fact is people have managed to climb Mount Everest without auxiliary oxygen and survive which at its peak is an equivalent value of 7% oxygen at sea level. When they got to the top all they could do was breathe and exert extremely small amounts of effort and some died without the auxiliary oxygen but some lived a long life after their adventure.
Since there is no research on the survivability of animals versus altitude relative to the survival rate of humans versus altitude we do not know at what point our technology will succumb to the remainder of the natural world. What we do know is that the first symptoms associated with lack of oxygen occur around 19.5% oxygen at sea level and by 7% at sea level the strongest and most adapted to high altitude can live provided they don’t have to do anything except live.
Based on this the next question would be how low will oxygen go burning all of our carbon-based fuels? According to the latest numbers oxygen would drop 3.3% if we could burn all of our known carbon-based fuels. At the rate we are burning them now that will take (3.3%/4ppm per year) 8,250 years. I would think that within those 8,250 years humans would no longer be burning fossil fuels because we have advanced enough to be using fusion.
But even after we quit burning fossil fuels we and all other animal life forms will still be using up O2 faster than the plants present ability to produce 02. In the case that we immediately convert from fossil fuels to fusion our concern is how long will it take until the oxygen is low enough to kill off life on earth. And considering in this case life to be even bacteria types which can survive down to about 2.5% oxygen it would take about (19.4%/0.0005ppm per year) 388 million years and all the oxygen would be gone.
Now 388 million years is a long time for us to comprehend but then the expected remaining lifetime for the sun before it goes nova is about 4.5 billion more years. So the earth will be barren of life almost 11.5 times longer than the oxygen will last. And since the total life of the sun from birth to when it goes nova is 9 billion years, and bacterial type life formed about 3.8 billion years ago and will probably die off in about 388 million years that means life on earth will exist for less than 1⁄2 the life of the sun before it nova’s into a Red Giant star. Based on this we can say we are in the twilight years of life on earth.
You would think that an intelligent species would try to find a balance where the plants were using up as much CO2 as the animals were using to keep the 02 either constant or rising at such a rate that in 4.5 billion years it would still be within the acceptable values for the life we know. Instead we are attempting to sequester CO2 and thus reduce the O2 output of the plants to take the oxygen away quicker. And then we laugh at those people that say they wonder if there is intelligent life on earth.
The graph above shows us that there is a long term trend (in red) of CO2 dropping. Just as gravity, the weakest known fundamental force, is the extremely long term dominant effect on the universe, the sequestering of CO2 by oceanic life forms using it to build their protective shells and the surface rocks and soil chemically reacting with the CO2 has been the dominant force in the amount of CO2 available in the atmosphere, even more so than geological activity (volcanoes and such) returns CO2 to the atmosphere. Even though there are times when other forces over drive it, in the extremely long term of hundreds of millions of years it is the dominant factor. And as we can see even though the CO2 has leveled off again around the 240ppm point (until humans inadvertently started putting CO2 back into the atmosphere) the sequestration point will inevitably result in the loss of all CO2 and thus all plant life and all animal life long before loss of 02 is the problem.
The past has shown that CO2 for some reason never seems to go below between 180ppm and 240ppm, which is apparently some type of balancing point?
This balancing point has the limitation in that, like during the carbonaceous period, there was excess oxygen being made indicating the O2 makers (plants/oceanic life) were finally limited in their ability to consume CO2 as their numbers dropped off and oxygen increased. Evolutionary wise this seemed to balance out until about 180 million years ago when evolutionary changes such as the Avis species and the demise of some large dinosaur species resulted in CO2 users decreasing CO2 and raising O2. From that point on the plants again dominated slightly and raised the oxygen in the atmosphere until mammals came along.
When mammals with warm blooded metabolisms became dominant they began reducing O2 without increasing CO2 which in all previous times had been a balancing act that kept things more balanced. Unfortunately this has resulted in a long term reduction of both Oxygen and CO2 which cannot result in a balancing adjustment.
How soon will it be before there is not enough CO2 in the atmosphere to support life? If we started at the 290ppm point (often pointed to as a gold standard called the pre-industrial level) and assume we have to go down to 100ppm (the point below which C3 plants die) at the natural sequestration rate it would take (190ppm/0.001016ppm per year) 187,007 years. A rather long time considering a single human lifetime but only about half as long as we homo sapiens have been around so far.
At the natural sequestration rate and the present value of 402ppm CO2 it will take approximately (302ppm/0.001016ppm per year) 297,103 years until the C3 plants die. Again, a long time compared to a human lifetime, and about as long as our species has been around so far. Considering it is unreasonable to think our societies would last this long since even though plants will survive humans ability to feed a large population will not be there long before 297,000 years from now as CO2 and thus plant life drops off.
Is this the fate we wish to strive for? Continuing to reduce CO2 through sequestration and non production? At least nature left a large enough deposit of carbon that can be used to keep a balance as long as the intelligent species decides to use it properly. So ultimately I guess the question is will humans become intelligent enough to prevent their kind from dying off prematurely?