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
Sulfur dioxide Sulfur dioxide Sulfur dioxide (also sulphur dioxide in British English) is the chemical compound with the formula . It is a toxic gas with a burnt match smell. It is released naturally by volcanic activity and is produced as a by-product of the burning of fossil fuels contaminated with sulfur compounds and copper extraction. SO is a bent molecule with "C" symmetry point group. A valence bond theory approach considering just "s" and "p" orbitals would describe the bonding in terms of resonance between two resonance structures. The sulfur–oxygen bond has a bond order of 1.5. There is support for