Carbon Dioxide is the foundation of the world's food chain. It's not pollution. Try studying some geology courses. The earth has had climates in the past with CO2 concentrations 10x higher or more than current levels, and life was thriving. Our planet is still stuck in a glacial climate. People don't realize how close our planet actually came to complete extinction a mere 20,000 years ago when the CO2 concentration was under 200ppm. This is approaching the lower boundary for plant life to survive.