How hard is this? Take two large fish tank, fill about 3 inches with water. In the first you have earth atmosphere (what you're breathing right now) and seal it. In the second tank: same atmosphere, same water then seal it, then add a whopping 200/ppm CO2. I know that's an order of magnitude greater than the amount the Warmers are contending is causing devastating changes on earth, but, hey, this is real science. Observe and monitor difference in the two tanks. Ideally this would be a double blind experiment where the team monitoring the tanks would not know which was the filled with the planet killing, life ending Sun destroying 200ppm of CO2 How hard is that?