ancient smoking astronauts from Earth, forced to go to another planet to smoke, due to all the PC concerns about second hand smoke
Or futural time-travelling earthlings forced to go to Venus due to second hand smoke?
BTW, if I was in Low Venereal Orbit (band name!) would I be able to see the surface at all even bits of it or is the cloud cover too thick.
The better question is where did ours all go to. Earth and Mars both have much thinner atmospheres than we could support, given our temperature and gravity. Last I heard, the best guess for us is that we lost most of it in the event which formed the Moon.
Acid rain. There’s evidence of that too in the modern Venusian climate.
Case closed.
♫ We rot in the molds of Venus,
We retch at her tainted breath.
Foul are her flooded jungles,
Crawling with unclean death. ♫
-"Noisy" Rhysling - *The Green Hills of Earth*
Well, not quite. The ancient Venusian civilization recognized the beginning effects of a climate change and in an attempt to halt it they outlawed all forms of technology that required any significant use of energy. This was necessary to eliminate the only known methods of producing large amounts of reliable, easily accessible and usable energy and the resulting by-products.
Unable to support the population using only hand tools and word of mouth communication, it quickly died back to a pre-industrial level. Even this could not offset the massive amounts of green-house gasses being produced by natural means (volcanoes, bovine flatuation, and the constant output of too many politicians and tabloid news services). Actually the attempts to burn the billions of rotting bodies only added to the problem (without mechanization they could not bury them fast enough).
A few remaining Venusians, realizing that life as they new it growing up would never be the same, climbed aboard the few remaining mothballed space ships (the politicians had killed the space program decades earlier) and moved to the next planet out from the sun. There they assimilated the small existing population and proceeded to while away the time building pyramids, drawing huge pictures on the ground, walking around with pots on their heads with small metal rods sticking out, and basically rebuilding there new home in their own image.
And building giant statues on Easter Island… You have to mention Easter Island.
Oh, and don’t forget to mention area 51, too…
How much CO2 is accounted for by organic sequestration – oil, coal, calcium carbonate, etc?
An ancient textbook I own from my long-ago college days, Holmes Principles of Physical Geology, says that eleven atmosphere’s worth of carbon and oxygen have been absorbed into the crust, after photosynthesis split the atmospheric CO2 into carbon and oxygen which were then absorbed separately, as oxides, carbonates and kerogen. I believe that modern estimates are even higher.
All we are left with is one fifth of a bar of oxygen in the atmosphere, and practically all the nitrogen that has been there all along.
Whatever else is missing was probably lost in the impact that formed the Moon; if we had an 80 bar atmosphere, like Venus, this loss could have been considerable.