Two 'new' greenhouse gases growing
March 24, 2009Two new greenhouse gases are accumulating in the atmosphere, according to an international research team led by scientists from the Scripps Institution of Oceanography in the US and CSIRO scientist, Dr Paul Fraser, from the Centre for Australian Weather and Climate Research.
Nitrogen trifluoride (NF3) and sulfuryl fluoride (SO2F2) are powerful greenhouse gases that have recently been discovered to be growing quickly in the global background atmosphere.
These gases are used in industrial processes, partly as alternatives to other harmful greenhouse and ozone depleting gases.
NF3 is used in the electronics industry - often as a replacement for perfluorocarbons (PFCs) - particularly in the manufacture of liquid-crystal flat-panel screens. SO2F2 is used as a replacement for methyl bromide, largely in structural fumigation applications. The new measurements of SO2F2 appear in a paper co-authored by Dr Fraser in the 12 March 2009 edition of the Journal of Geophysical Research.
"Information about the abundance of these gases in the atmosphere, their growth rates, lifetimes, and emissions is just emerging," Dr Fraser says.
"Currently the level of these gases in the atmosphere is low, but their concentration is growing. In addition, these gases have significant global-warming potential."
The first atmospheric observations of these gases from data collected around the world - particularly at Trinidad Head and La Jolla, California, and Cape Grim, Tasmania - will be presented at the GREENHOUSE 2009 conference.
"This research is likely to affect the revision of the Kyoto Protocol later this year," Dr Fraser says. "New emissions targets for the existing 'basket' of gases (carbon dioxide, methane, nitrous oxide, PFCs, hydrofluorocarbons, sulfur hexafluoride) are likely, as well as inclusion of the new greenhouse gases. A number of new signatories from the developed and developing world are also included in the revised Protocol."
Source: CSIRO Australia
Mar 10, 2009 |
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There's not enough info here for this to be anything more than "awareness" media.
Want to point out a source stating they're both artificial? Pretty sure Nitrogen Trifluoride is naturally occuring.
Present 0.053 ppt INCREASE per year, starting from 0.020 ppt 1978. In 1978 there existed LESS THAN ONE YEARS present rate of INCREASE.
"The mean global tropospheric concentration of NF3 has risen quasi-exponentially from about 0.02 ppt (parts-per-trillion, dry air mole fraction) at the beginning of our measured record in 1978, to a July 1, 2008 value of 0.454 ppt, with a rate of increase of 0.053 ppt per yr, or about 11% per year, and an interhemispheric gradient that is consistent with these emissions occurring overwhelmingly in the Northern Hemisphere, as expected."
http://www.agu.or...13.shtml
"The global tropospheric background concentration of SO2F2 has increased by 5 ± 1% per year from 0.3 ppt (parts per trillion, dry air mol fraction) in 1978 to 1.35 ppt in May 2007 in the Southern Hemisphere, and from 1.08 ppt in 1999 to 1.53 ppt in May 2007 in the Northern Hemisphere."
http://www.agu.or...62.shtml
Thanks for providing some of the information I asked for though.
And by the way, Nf3 is not naturally occuring, took some digging but I found it myself. Thanks for trying, len. If you wanted to actually dispute it you could have gone into whether N2 and F2 will bond without intervention from man, which it won't.
Unsurprisingly, the main uses of NF3 are the electronics industry where thin films are created, such as those in our LCD tvs and monitors. The main use of NF3 is in cleaning solar panels. There's another environmental impact for you solar guys to deal with.
As for it's greenhouse potential wiki has this to say.
"Although NF3 has a high global warming potential (GWP), its radiative forcing in the Earth's atmosphere is very small, as it is only released into the atmosphere in small quantities. Industrial applications involving NF3 routinely break it down as it is used, whereas the regulated compounds SF6 and PFCs are typically released.[5][6]
NF3 is a greenhouse gas, with a GWP 17,200 times greater than that of CO2 when compared over a 100 year period.[7][8][9] Its GWP would place it second only to SF6 in the group of Kyoto-recognised greenhouse gases, although NF3 is not currently included in that grouping. It has an estimated atmospheric lifetime of 740 years,[7] although recent work suggests a slightly shorter lifetime of 550 years (and a corresponding GWP of 16,800).[5]
In 2008, the estimated total atmospheric content of the gas was 5,400 metric tons, increasing at about 11 percent per year, more than the estimated 1,200 metric tons thought to be present in 2006.[10]
The projected maximum atmospheric concentration is less than 0.16 parts per trillion (ppt) by volume and will provide less than 0.001 Wm-2 of IR forcing.[11] A 2008 study utilizing an improved sampling technique has found a mean global tropospheric concentration of 0.454 ppt by dry air mole fraction.[12]"
"ALTHOUGH SEMICONDUCTORS remain the principal driver for electronic specialty gases, increased interest in photovoltaics is adding to the push.
Electronic gases are needed in thin-film deposition, such as chemical vapor deposition (CVD) or physical vapor deposition (PVD), technologies used to make a semiconductor or a photovoltaic cell.
The three major gases used in semiconductors, liquid crystal displays (LCDs) and photovoltaics are nitrogen trifluoride (NF3), silane (SiH4) and ammonia.
Emerging thin-film solar cells will be based on thin-film deposition technologies including CVD processing, says industry analyst Mike Corbett, managing partner of Linx Consulting, based in Boston, Massachusetts, US.
"Basically, tandem-cell thin-film solar cell production uses similar CVD tool sets as those used in the LCD industry. So as thin-film solar cells become more popular, there will be a high volume-growth potential for these gases," says Corbett.
According to US-based industrial gas supplier Air Products, solar capacity is growing at more than 30%/year."
("Strong photovoltaic and electronics sectors support nitrogen trifluoride, silane and ammonia demand" URL: http://www.icis.c...and.html Accessed: 3-28-2009)
Looks like the environmentalists are pushing far more toward global warming than they knew and more than their hated CO2 in the long run! :)