Owing to the presence of covalently bonded fluorine, halothane absorbs in the atmospheric window and is therefore a greenhouse gas. However, it is much less potent than most other chlorofluorocarbons and bromofluorocarbons due to its short atmospheric lifetime, estimated at only one year vis-à-vis over 100 years for many perfluorocarbons. Despite its short lifespan, halothane still has a global warming potential 47 times that of carbon dioxide, although this is over 100 times smaller than the most abundant fluorinated gases, and about 800 times smaller than the GWP of sulfur hexafluoride over 500 years. Halothane is believed to make a negligible contribution to global warming.