Ozone as concentrations in μg/m. The study of ozone concentration in the atmosphere started in the 1920s. The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer between about 10 km and 50 km above the surface (or between about 6 and 31 miles). However, even in this "layer", the ozone concentrations are only two to eight parts per million, so most of the oxygen there is dioxygen, O, at about 210,000 parts per million by volume. Ozone in the stratosphere is mostly produced from short-wave ultraviolet rays between 240
Vienna Convention for the Protection of the Ozone Layer Groups that help facilitate functions under the convention. A Multilateral Fund exists to aid developing nations transition from ozone-depleting chemicals using guidelines under the convention, which is administered by a Multilateral Fund Secretariat. The Multilateral Fund has aided thousands of projects in nearly 150 countries, preventing the usage of roughly 250,000 tons of ozone-depleting chemicals. Vienna Convention for the Protection of the Ozone Layer The Vienna Convention for the Protection of the Ozone Layer is a multilateral environmental agreement signed in 1985 that provided frameworks for international reductions in the production of chlorofluorocarbons due to their contribution to the destruction