During the Mesozoic era (The age of the dinosaurs), the Earth’s atmosphere had much higher CO2 concentration than current day, and that Era which was hundreds of millions of years in length, is noted for the explosion of life and overall warmth planet-wide. There weren’t even any ice caps on the planet, and the daily temps were around 120 degrees F.
Generally speaking, warmth is conflated with life, and to worry about it getting too hot is anti-science. We are never going to have a runaway greenhouse effect on Earth, as seen on Venus. We are too far from the Sun for that to happen.
It would take some serious evidence to convince me daytime high temperatures were around a 120 degrees. That is some animal killing heat, when there is a fair amount of humidity in the air.
We only get that kind of heat, now, in desert areas, and very rarely.
Near 90, I could believe that.
With the ice caps gone, and much larger oceans, I would expect the temperatures to be much milder over the whole planet, while averaging higher. Just not as much variation.
Oceans are the great moderator in temperatures.
Ferns were as tall as the dinosaurs!
This planets climate has been all over the place. Geologist have found evidence of river beds in the Sahara, that Mediterranean Sea had pretty dried up and land bridges between North Ameria and Eurasia, Britan and Europe, Japan and Asia.
Not too long ago a prehistoric shark fossil was found in the Peruvian desert.
You need to understand the solar output over the lifespan to-date to make such comment. I don’t think that you or your source have considered solar input with regards to you theory. When it comes to climate change the Sun calls the shots. Human impact on climate change is insignificant in comparison to the Sun’s impact. The fact that solar variation occurs over considerable time durations results in Solar derived data being excluded from most climate studies. Also neglected are dwell and lag times of Solar driven climate change. The preceeding statements are further complicated by orbital mechanics and the internal physics of the Sun itself. There are, at present, eleven known cycles of heating cooling of the planets based on orbital mechanics and Solar physics. Man’s contibution to climate change has about as much effect as pissing in a hurricane.