Nitrous oxide inside the cells, by a process catalyzed by the enzyme nitrous oxide reductase. Nitrous oxide has significant global warming potential as a greenhouse gas. On a per-molecule basis, considered over a 100-year-period, nitrous oxide has 298 times the atmospheric heat-trapping ability of carbon dioxide (), however, because of its low concentration (less than 1/1000 of that of ), its contribution to the greenhouse effect is less than one-third that of carbon dioxide, and also less than water vapour and methane. On the other hand, since 38% or more of the entering the atmosphere is the result of human activity, and
Chicago Climate Exchange were intended to still be facilitated. Until July 2010, CCX was operated by the public company Climate Exchange PLC, which also owned the European Climate Exchange. Richard Sandor, creator of the Sustainable Performance Group, founded the exchange and has been a spokesman for it. The exchange traded in emissions of six gases: carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, perfluorocarbons, and hydrofluorocarbons. CCX started trading in October 2003, prior to the commencement of trading in the European Union through the ETS system. IntercontinentalExchange (), a leading operator of regulated global futures exchanges, clearing houses and over-the-counter (OTC) markets, announced in