Global Atmosphere Watch was mere scientific interest, but of course, many scientists eventually wondered what effects these trace chemicals could have on the atmosphere, and on life. The GAW's genesis began as far back as the 1950s when the World Meteorological Organization began a programme of monitoring the atmosphere for trace chemicals, and also researching air pollution from a meteorological point of view. They were also responsible for monitoring ozone, establishing the Global Ozone Observing System (GO3OS) in 1957, in the International Geophysical Year. In 1968, the United Nations called for an international conference to address world environmental problems caused by rapid industrialization.
Modified atmosphere and its replacement with other gases can reduce or delay oxidation reactions and microbiological spoilage. Oxygen scavengers may also be used to reduce browning due to lipid oxidation by halting the auto-oxidative chemical process. The modification process generally lowers the amount of oxygen (O) in the headspace of the package. Oxygen can be replaced with nitrogen (N), a comparatively inert gas, or carbon dioxide (CO). A stable atmosphere of gases inside the packaging can be achieved using active techniques, such as gas flushing and compensated vacuum, or passively by designing “breathable” films. The first recorded beneficial effects of using modified