Photosynthesis, CO2, and Warming

During photosynthesis, plants use energy from sunlight to combine carbon dioxide with water and produce sugars and oxygen. Burning coal, oil, and gas transfers carbon stored in geological deposits into the atmosphere as CO₂. The rise in CO₂ and other greenhouse gases due to human activity is the main cause of modern global warming. Uptake of some CO₂ by plants and the ocean does not offset total human emissions.