ESRL Global Monitoring Division

Parameter	Formula	First Sample Date	Status
Carbon Dioxide	CO₂	1978-01-27	Ongoing
Methane	CH₄	1983-01-01	Ongoing
Carbon Monoxide	CO	1990-08-20	Ongoing
Molecular Hydrogen	H₂	1990-08-20	Ongoing
Nitrous Oxide	N₂O	1997-04-22	Ongoing
Sulfur Hexafluoride	SF₆	1997-04-22	Ongoing
Carbon-13/Carbon-12 in Carbon Dioxide	d¹³C (CO₂)	1994-06-20	Ongoing
Oxygen-18/Oxygen-16 in Carbon Dioxide	d¹⁸O (CO₂)	1994-06-20	Ongoing
Carbon-13/Carbon-12 in Methane	d¹³C (CH₄)	2001-01-08	Terminated - 2003-07-28
Methyl Chloride	CH₃Cl	2005-09-14	Terminated - 2018-03-29
Benzene	C₆H₆	2006-11-21	Terminated - 2018-03-29
Methylbenzene	C₇H₈	2006-11-21	Terminated - 2018-03-29
Ethane	C₂H₆	2005-09-14	Terminated - 2018-03-29
Ethylene	C₂H₄	2005-09-14	Terminated - 2018-03-29
Propane	C₃H₈	2005-09-14	Terminated - 2018-03-29
Propylene	C₃H₆	2005-09-14	Terminated - 2018-03-29
Isobutane	i-C₄H₁₀	2005-09-14	Terminated - 2018-03-29
n-Butane	n-C₄H₁₀	2005-09-14	Terminated - 2018-03-29
isopentane	i-C₅H₁₂	2005-09-14	Terminated - 2018-03-29
n-Pentane	n-C₅H₁₂	2005-09-14	Terminated - 2018-03-29
n-Hexane	n-C₆H₁₄	2005-09-14	Terminated - 2018-03-29
isoprene	C₅H₈	2006-11-21	Terminated - 2018-03-29
Acetylene	C₂H₂	2007-08-30	Terminated - 2018-03-29

Parameter	Formula	First Sample Date	Status
HFC-134a	CH₂FCF₃	1997-12-04	Ongoing
HCFC-22	CHF₂Cl	1997-12-04	Ongoing
CFC-12	CCl₂F₂	2010-01-11	Ongoing
Methyl Chloride	CH₃Cl	1997-12-04	Ongoing
HCFC-142b	CH₃CF₂Cl	1997-12-04	Ongoing
Halon-1211	CBrClF₂	1997-12-04	Ongoing
Methyl Bromide	CH₃Br	1997-12-04	Ongoing
CFC-113	CCl₂FCClF₂	1997-12-04	Ongoing
Dichloromethane	CH₂Cl₂	1997-12-04	Ongoing
Carbonyl Sulfide	COS	2000-05-08	Ongoing
HFC-152a	CH₃CHF₂	2000-05-08	Ongoing
Halon-2402	CBrF₂CBrF₂	2009-04-06	Ongoing
HFC-227ea	CF₃CHFCF₃	2011-02-23	Ongoing
HFC-365mfc	CH₃CF₂CH₂CF₃	2009-04-06	Ongoing
Methyl Chloroform	CH₃CCl₃	1997-12-04	Ongoing
CFC-11	CCl₃F	2010-01-11	Ongoing