CO2s effect on global warming reaches a ceiling, and it is close/ already reached ... more just helps plants and sea creatures grow :). We've had far higher CO2 levels in the atmosphere im the past and then the planet was much more bountiful with wildlife and giant animals and plants, on the land, in the ocean and air, everywhere.
Yes I'm a plant! provided I have adequate water, sunlight and minerals, I'd grow faster in the carbon dioxide rich atmosphere, produce oxygen at a greater rate, reduce the CO2 and increase the oxygen just as in the carboniferous period when the carbon dioxide levels were much much higher. I'd trap carbon in my leaves, stem, fruits and seeds, which if not eaten would eventually build up as sediment called soil, or peat, or if I'm particularly woody, as coal.
