Gases

Why I believe that global warming is real and man made. Chemist use gas chromatography to measure the amount of various gases in a sample. The process is quite simple. An one quarter inch aluminum tube about 40 feet long is filled with sand size particles of polypropylene a white plastic material that is almost totally inert. The tube is then twisted into a spring like shape and placed in a one cubic foot metal box. The box acts like an oven and is set at about 400 degrees. The front of the tube is the sample input port and the exit of the tube has a volt meter. An inert gas like helium is passed through the tube at a steady rate and the volt meter measures the voltage as the gas exits. When the voltage stabilizes the instrument is ready for use. One one milliliter sample using a syringe is introduced into the input. The sample is pushed through the tube by the helium and when it exits the volt meter record the results on a graph. Every gas has a different graph and millions of samples have been graphed and the computer keeps a record of each. The graph shows not only what the gas is but how much. For example a one milliliter sample of air is injected. Air contains about 80% nitrogen, 19% oxygen, 0.4% carbon dioxide and a small amount of a half dozen other gases, things like argon. As the gases are pushed through the tube by the helium stream the lighter gases move faster and they are separated out by their weight. Nitrogen weighs 28, oxygen 32 and carbon dioxide 40 so the nitrogen would be the first out followed by the oxygen and lastly the carbon dioxide. The computer then calculates the amount of each gas. Down in Antarctica the ice is about three miles deep and they drill down using a steal tube about 4 inches in diameter and they bring of samples at various debts. Each year the thaw and freeze form a ring in the core samples and they have gone back 2.7 million years. Using a hypodermic needle the take a sample of the air from each ring and test it in the gas chromatograph. For all of those years the CO2 levels ranged between 200 and 300 parts per million up(ppm) until the start of the industrial revolution in 1750 when the world started burning coal. Since that time the CO2 levels have risen steadily and today they are over 400 ppm and rising. Its possible that this rise was just a coincidence and there is another unknown cause but that is not likely.