Ozone depletion iodine atoms participate in analogous catalytic cycles. However, fluorine atoms react rapidly with water and methane to form strongly bound HF in the Earth's stratosphere, while organic molecules containing iodine react so rapidly in the lower atmosphere that they do not reach the stratosphere in significant quantities. A single chlorine atom is able to react with an average of 100,000 ozone molecules before it is removed from the catalytic cycle. This fact plus the amount of chlorine released into the atmosphere yearly by chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) demonstrates the danger of CFCs and HCFCs to the environment. The ozone
Tropospheric ozone Photolysis of ozone occurs at wavelengths below approximately 310-320 nano-meters . This reaction initiates the chain of chemical reactions that remove carbon monoxide, methane, and other hydrocarbons from the atmosphere via oxidation. Therefore, the concentration of tropospheric ozone affects how long these compounds remain in the air. If the oxidation of carbon monoxide or methane occur in the presence of nitrogen monoxide (NO), this chain of reactions has a net product of ozone added to the system. Ozone in the atmosphere can be measured by remote sensing technology, or by "in-situ" monitoring technology. Because ozone absorbs light in the UV