Plants are amazing little chemical ... well, plants. In the process of photosynthesis, they take carbon dioxide and water and turn it into sugar and breathable oxygen. We have been adding carbon dioxide to Earth's atmosphere at dangerously high rates, leading to global warming, but could we reverse the process by doing what plants do on some kind of industrial scale?
Maybe. There are some groups working on the problem, called
artificial photosynthesis. The main difficulty is that it requires energy to turn a planet-warming molecule of carbon dioxide into a nicely breathable molecule of oxygen. Plants solve this problem nicely using solar energy and a very complex
chain of reactions involving many steps and many catalysts. If we are to engage in artificial photosynthesis on an industrial scale, we will need to find cheap (preferably not very polluting) catalysts and probably a
different chain of reactions.
But why not just do it the old-fashioned way? Plants require a lot of water and other resources to do their neat little chemical trick, so we might find a more efficient way to do it in the lab. Still, many climate change agreements and proposals do involve using "offsets" like planting trees to eat up some of the carbon dioxide produced by industry. Natural photosynthesis (aka plants!) also provide lots of side benefits not produced by artificial photosynthesis (like water filtration, storm surge absorption, food, shelter, beauty - the list goes on).
