Are air pressure variations over geological times controlling Earth’s climate?

Fossil of a Pterodactyl, a flying lizard, called Quetzalcoatlus that lived about 70 million years ago, just a few million years before the disappearance of the dinosaur, is the largest Pterodactyl that has ever been found. Pterodactyls were not dinosaurs but belonged to another branch of reptiles. They were probably warm blooded. The name Quetzalcoatlus is taken from the Aztec serpent god. If Quetzalcoatlus would exist today they would have a big problem, they couldn’t fly. They were too heavy to take to the air in today’s skies. It was as large as a Cessna airplane and it is estimated that it weighted about 200 kilogram.

Yet, we know they manage to fly 70 million years ago. The most logical reason they were able to fly, was that the air pressure near sea level was much higher than today. It is estimated to have to have been about 4 atmospheres for the animal to be able to fly.

Here is a lecture on the Quetzalcoatlus flight by astronaut Don Pettit who made me start to think about the potential impacts from pressure variations over geological times.

And if air pressure at that time was that high, this also increased global temperature because of adiabatic pressure. Higher pressure, higher temperature. What do we know of the conditions of the atmosphere over geological times? Not that much. Adiabatic pressure differences cause temperature differences between high altitude (mountains) and sea level. The pressure at Mount Everest is about 30% of that at sea level.

We do know proxy values for CO2 as the stomata density on leaves from fossils can be calculated, which give values for CO2 levels. It is more difficult to know air pressure and the relationship between oxygen and nitrogen in the atmosphere over geological times. Variations of CO2 levels are claimed by advocates of the dangerous human caused global warming theory to be the dominant force for climate change, despite lack of any evidence for that being the case. Could it instead be cause by air pressure variations?

Given that Quetzalcoatlus is a kind of proxy for air pressure for the period right before the KT boundary, what if variations of air pressure drive climate change or at least are an important part of it?

Imagen that gases released from volcanic activity fills the atmosphere with gases over time and that volcanic and lava lake gas release varies over geological times. At the same time we have loss of gases to space driven by the solar wind which is going on all the time. If volcanic activity is low, Earth is losing gases from the atmosphere. If volcanic activity is high, air pressure is increasing.

I looked at this graph over CO2 and temperature over geological time. I know of two outgassing events. The Siberian trap during the Permian extinction 252 million years ago and the Deccan trap which formed the Western Ghat in India 66 million years ago just before the KY-boundary. And then we have the breakup of Pangea which occurred in steps during the age of the dinosaurs which formed the Atlantic Ocean of today.

At the time of the Permian extinction, which was the largest known extinction, and is associated with the Siberian trap 252 million years ago we can see a sharp increase in temperature and also an increase of CO2. At the time of the Deccan trap near the time of the KT boundary the temperature was also high.

I also found out about a fossil called Argentavis Magnificens which was a bird that lived 6 million years ago that weighted about 60-70 kilogram. It is the largest flying bird we know to have lived. The temperature at the time was lower that of the time of Quetzalcoatlus but higher than that of today. So, the pressure was probably higher than today too. During the Carboniferous and late Permian era large dragonfly insects existed.

I often see claims by advocates of CAGW that the heat of Venus, where the temperature at the surface is warm enough to melt lead, that this is caused by high CO2 levels. This is completely nonsense, as the warm surface is caused by extremely high pressure. The pressure at the surface is 100 atm which is the same pressure 1000 meters bellow the surface of the oceans. Compress the atmosphere to that pressure and you get these temperatures. It doesn’t matter if the atmosphere is mostly CO2 as on Venus or a combination of Nitrogen and Oxygen as we have on Earth. If you have had the same gases on Venus as we have on Earth and it was 100 atm at the surface then you would have the same temperature because of the adiabatic pressure. Because Venus is closer to the Sun than the Earth, it should be warmer from more solar energy. Calculation show that the temperature should be about 50 degree Celsius. If you look at temperature profile of Venus and look at the upper part of its atmosphere then you find that at 1 atm the observed temperature is about 50 C, Coincidence? I think not.

Of the 3 planets Venus, Earth and Mars, Earth is different because Earth has a strong magnetic field and the other two have not. Because water molecules are dipoles, water are kept on Earth as these molecules less easily are lost into space, while the other two planets have no magnetic fields that protect them from water loss. Water has a stabilizing effect on Earth’s climate. Earth is unique in another way as we have tidal effect because of the Moon. This cause turbulence in the upper atmosphere that sends away molecules of oxygen and nitrogen into space. Add to that, that the tidal effect earlier in Earth’s history was much stronger then as the Moon’s orbit was closer than it is today.

A surprise to me has been that climate researchers don’t seem to connect air density variations to climate change over geological times. Instead, they connect climate change to variations of CO2. The correlation between CO2 and temperature is poor, but I can see correlations between CO2 in the age of mammals and temperature. But there is no evidence that CO2 variations is a main climate driver which I show here. https://www.coolingnews.com/climate-hysteria-part1.html

Higher pressure also affect the estimated proxy for CO2 values. CO2 values during higher pressure are too high and should be lowered during higher pressure as more CO2 molecules are absorbed by stomata with higher pressure.

Climate scientists seem to think that the air pressure over geological time has been constant.

To conclude, CO2 variations are not what caused climate variations over geological times, but air pressure variations were.

What do you think?

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