Global Warming and Climate Change} How do I, we, us, get the world behind my, our, anybody SOLUTION!

Could mankind survive, when the planet's carbon dioxide levels in the atmosphere reach below 150 parts per million? This is the level where C3 plants can no longer survive, although C4 and cam plant can, even if their production value does decrease. While mankind could survive, on a planet covered by deserts and growing all of there food in greenhouse type structures that would have to be airtight, so that carbon dioxide could be pumped into them. My best guess would be that because of all the treeless and plant less landmass, it would be very hot during the day, because of the sun's energy being converted straight into heat, but at night freezing cold because all of the heat generated during the day would escape straight out to space with little or no cloud cover. These temperature extremes would create havoc on the weather. Without C3 plant being around for grazing animals to feed on, many species would either go extinct, on their numbers would be very limited by whatever plant life would still be around. Even C4 and cam plant's production would become more and more limited, as co2 levels keep dropping, along with much lower rainfall amounts everywhere around the planet. And over time, oxygen levels would slowly begin to drop, until mankind would have to move into those same dome's that are keeping plant life alive! How many people could live in such a system, I have no idea. Once inside such a domed structure, there would be no more carbon sequestration, so any carbon dioxide inside could be recycled forever, the same with all the other requirement's of life, but after some time man would not be able to leave these domes, without wearing a space type suit, and the climate outside could very well kill you if the temperature extremes become what "I" think they would. There is, of course, the chance that the planet would enter into a forever ice age, no matter how much sunlight is hitting the ground and being converted to heat to offset the cold, upon losing all of that heat every night. All of this would depend on how fast C3 plants would disappear, and be replaced by deserts because this would release trapped carbon in the soil's, keeping C3 plant alive elsewhere on the planet. I can be reached at   danielkadavy212@gmail.com  or by phone @ 402-890-7946 Thank you. What do you see life, would be like on the planet with C3 plant's gone?