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Gases

N2O SF6 CFC-11 CFC-12 CFC-113 CCl4 CH3CCl3 C2Cl4 CH2Cl2 HCFC-22 HCFC-141b HCFC-142b HFC-32 HFC-125 HFC-134a HFC-143a HFC-152a HFC-227ea HFC-365mfc HFC-236fa halon-1211 halon-1301 halon-2402 CH3Br CH3Cl OCS PFC-116 CF4 NF3 SO2F2 C2H6 (Ethane) C3H8 (Propane)

HCFC-142b (Chlorodifluoromethane)

There are two GML programs that measure HCFC-142b. The longest and most complete measurement of HCFC-142b is from the HATS flask GC-MSD program (data displayed below). The CATS in situ GCs also measure HCFC-142b, however the data are less precise than the flask measurements. For further information on HCFCs click here.

Flask HCFC-142b data

MS flask data by site

CATS in situ data
Supplemental Info and Data Use Policy
New in 2022: Continental U.S. emissions are located on the US Potent GHG Tracker website.

HCFC-142b

Atmospheric dry mole fractions (parts-per-trillion or ppt) of HCFC-142b measured by GC-MSD in the HATS flask program. Each point represents a monthly mean at one of 8-12 stations: Alert, Canada (ALT), Summit Greenland (SUM), Barrow, Alaska (BRW), Mace Head, Ireland (MHD), Trinidad Head, California (THD), Niwot Ridge, Colorado (NWR), Cape Kumukahi, Hawaii (KUM), Manua Loa, Hawaii (MLO), American Samoa (SMO), Cape Grim, Australia (CGO), Palmer Station, Antarctica (PSA), South Pole, Antarctica (SPO).

HCFC-142b

Zonal mean dry mole fractions (ppt) are estimated from the flask data by equally weighting monthly mean measurements in each latitude band. Small gaps (less than 6 months) are interpolated prior to averaging. Solid lines are used for Northern hemispheric measurements and dashed for the Southern hemisphere.

Selected Publications

  • Montzka, S. A., B. D. Hall, and J. W. Elkins (2009), Accelerated increases observed for hydrochlorofluorocarbons since 2004 in the global atmosphere, Geophys. Res. Lett., 36, L03804, doi:10.1029/2008GL036475.
  • Montzka, S.A., R.C. Myers, J.H. Butler, and J.W. Elkins, Early trends in the global tropospheric abundance of hydrochlorofluorocarbon-141b and -142b, Geophys. Res. Lett., 21, 2483-2486, 1994.