Organization(s):

NOAA logo National Oceanic and Atmospheric Administration (NOAA), Earth System Research Laboratory (ESRL)


What does this program measure?

The Mauna Loa Observatory CATS (Chromatograph for Atmospheric Trace Species) CATS program measures the following, where 'ppt' is parts-per-trillion, and 'ppb' is parts-per-billion.

Category
Chemical
Chemical Formula
Units
Chlorofluorocarbons
Trichloro(mono)fluoromethane
CFC-11 (CCl3F)
ppt
Chlorofluorocarbons
Dichlorodifluoromethane
CFC-12 (CCl2F2)
ppt
Chlorofluorocarbons
Trichlorotrifluoroethane
CFC-113
(CCl2F-CClF2)
ppt
Hydrochlorofluorocarbons
Chlorodifluoromethane
HCFC-22 (CHClF2)
ppt
Methyl Halides
Chloroform
CHCl3
ppt
Methyl Halides
Methyl Bromide
CH3Br
ppt
Chlorinated Solvents
Carbon Tetrachloride
CCl4
ppt
Chlorinated Solvents
Halon-1211
CBrClF2
ppt
Chlorinated Solvents
Methyl Chloride
CH3Cl
ppt
Other Measurements
Nitrous Oxide
N2O
ppb
Other Measurements
Methyl Chloroform
CH3CCl3
ppt
Other Measurements
Carbonyl Sulfide
COS
ppt


How does this program work?

Electron Capture Detection-Gas Chromatography is done continuously at MLO.


Why is this research important?

All of these gases are greenhouse gases. Chlorofluorocarbons (CFCs), Hydrochlorofluorocarbons (HCFCs), methyl halides (CH3Br and CH3Cl), and N2O deplete stratospheric ozone. Chlorinated solvents are involved in regional air quality.


Are there any trends in the data?

CFCs, CH3CCl3, CH3Br, and CCl4 are decreasing because of the Montreal Protocol. N2O, HCFCs, and HFCs are increasing.


How does this program fit into the big picture?
What is it's role in global climate change?

All of these gases are greenhouse gases to a certain degree.


Comments and References

Butler , J.H., J.W. Elkins, B.D. Hall, S.O. Cummings, and S.A. Montzka, A decrease in the growth rates of atmospheric halon concentrations, Nature, 359, 403-405, 1992.

Butler, J.H., J.W. Elkins, T.M. Thompson, and K.B. Egan, Tropospheric and dissolved N 2O of the west Pacific and east Indian Oceans during the El Niño-Southern Oscillation event of 1987, J. Geophys. Res. , 94 (D12), 14865-14877, 1989.

Dlugokencky, E.J., T. J. Conway, P. P. Tans, S. A. Montzka, and J. W. Elkins, Recent trends in greenhouse gases, in Sixth Symposium on Global Change Studies, pp. 202-204, 1995.

Elkins, J.W., T.M. Thompson, T.H. Swanson, J.H. Butler, B.D. Hall, S.O. Cummings, D.A. Fisher, and A.G. Raffo, Decrease in the growth rates of atmospheric chlorofluorocarbons 11 and 12, Nature, 364 (August 26, 1993), 780-783, 1993.

Montzka, S.A., J.H. Butler, R.C. Myers, T.M. Thompson, T.H. Swanson, A.D. Clarke, L.T. Lock, J.W. Elkins, Decline in the tropospheric abundance of halogen from halocarbons: Implications for stratospheric ozone depletion., Science, 272, 1318-1322, 1996.


Lead Investigator(s):

James W. Elkins
303-497-6224
Geoffrey S. Dutton

303-497-6086


MLO Contact(s):

Aidan Colton
808-933-6965 (x233)
Paul Fukumura
808-933-6965 (x223))


Web Site(s)

http://www.esrl.noaa
.gov/gmd/hats


http://www.esrl.noaa
.gov/gmd/hats/insitu/cats/


Date Started

1977


Related Programs

Halocarbon Flasks
Cooperative Global Air Sampling
Greenhouse Gases




Photographs:

Stealth Gas ChromatographCATS GC

Stealth GC Gas Tank SystemCalibration tanks