Green house gasses prevent the sun’s energy from completely leaving the planet. Without that trapping effect, Earth would be a ball of ice incapable of hosting much in the way of life.
Throughout the numerous ice ages Earth has been through, including the last one where we find ourselves at the tail end of, there has never been a moment free of green house gasses. No matter how long the ice ages have been or severe, there has never been one that covered the totality of the planet.
Green house gasses are not some threat to combat. It is something to be grateful for.
According to the British Geological Survey, The greenhouse effect:
“‘Greenhouse gases’ are crucial to keeping our planet at a suitable temperature for life. Without the natural greenhouse effect, the heat emitted by the Earth would simply pass outwards from the Earth’s surface into space and the Earth would have an average temperature of about -20°C.”
The current level of gasses makes it possible for animals to live and thrive. Seeking to reduce them is seeking the destruction of many species. How can people claim they care about the environment when they seek to destroy the environment? Destruction is the only thing reducing green house gasses will do. There is nothing positive that comes from reducing them.
To put simply, greenhouse gasses are good. Reducing them is bad. Greenhouse gasses keeps the animals alive. Reducing them kills animals.
As for those who believe Earth has never been warmer, they are lacking any understanding of historic temperatures. Earth has been hotter numerous times. There has not been just a single ice age, but several. Those times between the ice ages resulted in no ice at either pole.
It was only 90 million years ago when the dinosaurs ruled the planet. There was no ice as a result of Earth being far warmer than it is today. Had there been an ice age, the lizards would have frozen to death in places where fossils are found, like Antarctica.
Greenhouse gasses are not a threat to the planet. Seeking to reduce them is.
As for CO2, there are only trace amounts in the upper atmosphere. Reducing them by 100% would have no impact, since all life released carbon even after death. The only thing reducing CO2 would accomplish would be to have fewer plants, since it is what plants need to survive.
CO2 is one of the heaviest elements in the air, which keeps it close to the ground. If it were lighter, plants would not do well.
Those current levels of gasses are necessary for the balance of life that exists today. Anyone who believes otherwise has no idea what the science makes clear. There are no shortage of people claiming to believe science who have no idea what they are talking about.