A gas used in the production of flat-panel displays for HDTVs is 17,200 times better at trapping heat in the atmosphere over a hundred-year period than carbon dioxide, the gas most associated with global warming.
Michael Prather, of the University of California at Irvine, has completed a study into nitrogen trifluoride (NF3), which he describes as the “missing greenhouse gas”.
Yet the synthetic chemical produced in industrial quantities is not included in the Kyoto Protocol’s basket of greenhouse gases or in national reporting under the United Nations Framework Convention on Climate Change (UNFCCC).
Concerns have led Toshiba Matsushita Display Technology to avoid using the gas, although Air Products, which produces it for the electronics industry, said very little NF3 is released into the atmosphere.
Prather argues that as the gas is not controlled in the same way as other greenhouse gases, companies may be careless with it.
The scientist, whose findings are reported in the latest issue of the journal Geophysical Research Letters, is calling for NF3 emissions to be monitored.
It wasn’t included in the Kyoto agreement when it was signed by 181 countries in 1997 because the compound’s manufacture at the time was miniscule.
But increased use of NF3 in flat-panel display production means that’s no longer the case.
NF3’s global-warming potential is second only to sulfur hexafluoride (SF6), the worst-rated greenhouse gas on the Kyoto list.
Prather notes that the increased production of NF3 means that emission levels of the gas could potentially increase.
“With 2008 production equivalent to 67 million metric tons of CO2, NF3 has a potential greenhouse impact larger than that of the industrialised nations’ emissions of PFCs or SF6 (sulfur hexafluoride), or even that of the world’s largest coal-fired power plants,” writes Prather.
“If released, annual production would increase the lower atmospheric abundance by 0.4 ppt, and it is urgent to document NF3 emissions through atmospheric observations.”