The raw materials that solar energy makes into carbohydrates are and water.
Carbon dioxide furnishes the carbon and oxygen, and water furnishes the hydrogen for carbohydrate, .
Like solar energy, the quantity of and water form another elementary limit on food production. So the silver lining in the growing cloud of atmospheric that may warm the planet is more raw material for photosynthesis. Optimists see a stimulation of photosynthesis from more , and pessimists see little benefit or even harm. Compare the following two headlines. On September 18, 1992.