Emissions trading market in pollution-licenses is more widely applicable than the market in emission-licenses. The international community began the long process towards building effective international and domestic measures to tackle GHG emissions (carbon dioxide, methane, nitrous oxide, hydroflurocarbons, perfluorocarbons, sulphur hexafluoride) in response to the increasing assertions that global warming is happening due to man-made emissions and the uncertainty over its likely consequences. That process began in Rio in 1992, when 160 countries agreed the UN Framework Convention on Climate Change (UNFCCC). The UNFCCC is, as its title suggests, simply a framework; the necessary detail was left to be settled by the
Carbon dioxide of hydrogen by steam reforming and the water gas shift reaction in ammonia production. These processes begin with the reaction of water and natural gas (mainly methane). This is a major source of food-grade carbon dioxide for use in carbonation of beer and soft drinks, and is also used for stunning animals such as poultry. In the summer of 2018 a shortage of carbon dioxide for these purposes arose in Europe due to the temporary shut-down of several ammonia plants for maintenance. Acids liberate from most metal carbonates. Consequently, it may be obtained directly from natural carbon dioxide springs, where