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Barrow Atmospheric Baseline Observatory, United States [BRW]


  • Country: United States Country Flag
  • Latitude: 71.3230° North
  • Longitude: 156.6114° West
  • Elevation: 11.00 masl
  • Time Zone: Local Standard Time + 9.0 hour(s) = UTC


  • Address: Barrow Atmospheric Baseline Observatory
    P.O. Box 888
    Utqiaġvik, Alaska, 99723-0888, United States
  • Phone: (907) 852-6500
  • Fax: (907) 852-4622


Cooperating Agencies

The Barrow Atmospheric Baseline Observatory, established in 1973, is located near sea level 8 km east of Utqiaġvik (formerly Barrow), Alaska at 71.32 degrees north. This facility is staffed by 2 engineers/scientists who often commute to work in winter on snow machines. Due to its unique location, dedicated and highly-trained staff, excellent power and communications infrastructure, the site is host to numerous cooperative research projects from around the world.

BRW's location receives minimal influence from anthropogenic effects. It is about 8 km northeast of the village of Utqiaġvik and has a prevailing east-northeast wind off the Beaufort Sea. It is attended at least 5 days a week for routine inspection and maintenance of the instrumentation. Although the measurements at BRW are made over open tundra, there are large lagoons and a number of lakes in the vicinity, and the Arctic Ocean is less than 3 km northwest of the site. Because of its proximity to these bodies of water and the fact that the prevailing winds are off the Beaufort Sea, BRW is perhaps best characterized as having an Arctic maritime climate affected by variations of weather and sea ice conditions in the Central Arctic.

GML Projects at Barrow Atmospheric Baseline Observatory

Carbon Cycle Surface Flasks

Parameter Formula First Sample Date Status
Carbon Dioxide CO2 1971-04-25 Ongoing
Methane CH4 1983-04-06 Ongoing
Carbon Monoxide CO 1988-07-24 Ongoing
Molecular Hydrogen H2 1988-07-24 Ongoing
Nitrous Oxide N2O 1997-05-02 Ongoing
Sulfur Hexafluoride SF6 2023-01-25 Ongoing
Sulfur Hexafluoride SF6 1997-05-02 Ongoing
Carbon-13/Carbon-12 in Carbon Dioxide d13C (CO2) 1990-01-06 Ongoing
Oxygen-18/Oxygen-16 in Carbon Dioxide d18O (CO2) 1990-01-06 Ongoing
Carbon-13/Carbon-12 in Methane d13C (CH4) 1998-01-03 Ongoing
D/H in Methane dD (CH4) 2005-04-01 Terminated - 2010-03-12
HFC-134a CH2FCF3 2023-01-25 Ongoing
HCFC-22 CHF2Cl 2023-01-25 Ongoing
CFC-12 CCl2F2 2023-01-25 Ongoing
Methyl Chloride CH3Cl 2023-01-25 Ongoing
Methyl Chloride CH3Cl 2005-05-20 Terminated - 2018-06-21
CFC-114 CFC-114 2023-01-25 Ongoing
HCFC-142b CH3CF2Cl 2023-01-25 Ongoing
Halon-1211 CBrClF2 2023-01-25 Ongoing
Methyl Bromide CH3Br 2023-01-25 Ongoing
CFC-11 CCl3F (ion 103) 2023-01-25 Ongoing
HCFC-141b CH3CCl2F 2023-01-25 Ongoing
Methyl Iodide CH3I 2023-01-25 Ongoing
CFC-113 CCl2FCClF2 2023-01-25 Ongoing
Dichloromethane CH2Cl2 2023-01-25 Ongoing
Chloroform CHCl3 2023-01-25 Ongoing
Methyl Chloroform (97) CH3CCl3 2023-01-25 Ongoing
Carbon Tetrachloride CCl4 2023-01-25 Ongoing
Methelyne Bromide CH2Br2 2023-01-25 Ongoing
Perchloroethylene (PCE) C2Cl4 2023-01-25 Ongoing
Bromoform CHBr3 2023-01-25 Ongoing
Benzene C6H6 2023-01-25 Ongoing
Benzene C6H6 2007-02-16 Terminated - 2018-06-21
Carbonyl Sulfide COS 2023-01-25 Ongoing
HCFC-21 CHCl2F 2023-01-25 Ongoing
HFC-152a CH3CHF2 2023-01-25 Ongoing
HCFC-124 CHClFCF3 2023-01-25 Ongoing
Methylbenzene C7H8 2007-02-16 Terminated - 2018-06-21
Carbon Disulfide CS2 2023-01-25 Ongoing
Ethane C2H6 2005-05-20 Terminated - 2018-06-21
Ethane C2H6 2023-01-25 Ongoing
Ethylene C2H4 2023-01-25 Ongoing
Ethylene C2H4 2005-05-20 Terminated - 2018-06-21
Propane C3H8 2023-01-25 Ongoing
Propane C3H8 2005-05-20 Terminated - 2018-06-21
Propylene C3H6 2005-05-20 Terminated - 2018-06-21
Propylene C3H6 2023-01-25 Ongoing
Isobutane i-C4H10 2005-05-20 Terminated - 2018-06-21
Isobutane i-C4H10 2023-01-25 Ongoing
n-Butane n-C4H10 2023-01-25 Ongoing
n-Butane n-C4H10 2005-05-20 Terminated - 2018-06-21
isopentane i-C5H12 2005-05-20 Terminated - 2018-06-21
isopentane i-C5H12 2023-01-25 Ongoing
n-Pentane n-C5H12 2005-05-20 Terminated - 2018-06-21
n-Pentane n-C5H12 2023-01-25 Ongoing
n-Hexane n-C6H14 2023-01-25 Ongoing
n-Hexane n-C6H14 2005-05-20 Terminated - 2018-06-21
isoprene C5H8 2007-02-16 Terminated - 2018-06-21
Halon-1301 CF3Br 2023-01-25 Ongoing
Halon-2402 CBrF2CBrF2 2023-01-25 Ongoing
HFC-143a CH3CF3 2023-01-25 Ongoing
HFC-227ea CF3CHFCF3 2023-01-25 Ongoing
HFC-365mfc CH3CF2CH2CF3 2023-01-25 Ongoing
CFC-115 CClF2CF3 2023-01-25 Ongoing
HFC-125 CHF2CF3 2023-01-25 Ongoing
CFC-13 CClF3 2023-01-25 Ongoing
HFC-23 CHF3 2023-01-25 Ongoing
PFC-218 C3F8 2023-01-25 Ongoing
Acetylene C2H2 2007-05-25 Terminated - 2018-06-21
Acetylene C2H2 2023-01-25 Ongoing
HFC-32 CH2F2 2023-01-25 Ongoing
HFC-134 CHF2CHF2 2023-01-25 Ongoing
Halon-1011 CH2BrCl 2023-01-25 Ongoing
Carbon-14/Carbon in Methane D14C (CH4) 2013-03-26 Terminated - 2021-02-22
Carbon-13/Carbon-12 in Carbon Monoxide d13C (CO) 1990-03-28 Terminated - 1996-08-21
PFC-14 CF4 2023-01-25 Ongoing
PFC-116 CF3CF3 2023-01-25 Ongoing
Trifluoroamine NF3 2023-01-25 Ongoing
Sulfuryl Fluoride SO2F2 2023-01-25 Ongoing
HFC-236fa CF3CH2CF3 2023-01-25 Ongoing
HCFC-133a CH2ClCF3 2023-01-25 Ongoing
CFC-112 CCl3CClF2 2023-01-25 Ongoing
Trichloroethylene (TCE) C2HCl3 2023-01-25 Ongoing
HFO-1234yf CH2=CFCF3 2023-01-25 Ongoing
HFC-1234zeE CHF=CHCF3 2023-01-25 Ongoing
ethylene dichloride (1,2 DCE) CH2ClCH2Cl 2023-01-25 Ongoing
HCFC-123 CHCl2CF3 2023-01-25 Ongoing
Morpholine C5F11NO 2023-01-25 Ongoing
Perfluorotriethylamine (PFTEA) (C2F5)3N 2023-01-25 Ongoing
Perfluorotripropylamine (PFTPA) (C3F7)3N 2023-01-25 Ongoing
HFC-245fa 2023-01-25 Ongoing

Carbon Cycle In Situ Observatory

Parameter Formula First Sample Date Status
Carbon Dioxide CO2 1973-07-24 Ongoing
Methane CH4 1986-01-29 Ongoing
Carbon Monoxide CO 1991-09-11 Ongoing
Nitrous Oxide N2O 2013-06-27 Ongoing

HATS Flask Sampling

Parameter Formula First Sample Date Status
HFC-134a CH2FCF3 1994-11-25 Ongoing
HCFC-22 CHF2Cl 1992-04-08 Ongoing
CFC-12 CCl2F2 2010-01-04 Ongoing
Methyl Chloride CH3Cl 1994-04-15 Ongoing
HCFC-142b CH3CF2Cl 1992-04-08 Ongoing
Halon-1211 CBrClF2 1992-02-14 Ongoing
Methyl Bromide CH3Br 1994-01-26 Ongoing
HCFC-141b CH3CCl2F 1993-01-07 Ongoing
CFC-113 CCl2FCClF2 1992-02-14 Ongoing
Dichloromethane CH2Cl2 1994-04-15 Ongoing
Perchloroethylene (PCE) C2Cl4 1993-12-11 Ongoing
Carbonyl Sulfide COS 2000-03-25 Ongoing
HFC-152a CH3CHF2 2000-08-03 Ongoing
Halon-2402 CBrF2CBrF2 1995-02-25 Ongoing
HFC-227ea CF3CHFCF3 2011-06-13 Ongoing
HFC-365mfc CH3CF2CH2CF3 2009-08-10 Ongoing
Methyl Chloroform CH3CCl3 1992-04-08 Ongoing
CFC-11 CCl3F 2010-01-04 Ongoing

HATS In Situ Observatory

Parameter Formula First Sample Date Status
Nitrous Oxide N2O 1998-06-16 Ongoing
Sulfur Hexafluoride SF6 1998-06-15 Ongoing
HCFC-22 CHF2Cl 1998-11-05 Ongoing
CFC-12 CCl2F2 1998-06-15 Ongoing
Methyl Chloride CH3Cl 1998-08-27 Ongoing
HCFC-142b CH3CF2Cl 1998-09-03 Ongoing
Halon-1211 CBrClF2 1998-06-15 Ongoing
CFC-113 CCl2FCClF2 1998-06-16 Ongoing
Carbon Tetrachloride CCl4 1998-06-16 Ongoing
Methyl Chloroform CH3CCl3 1998-06-16 Ongoing
CFC-11 CCl3F 1998-06-16 Ongoing

Aerosol Surface In-Situ

Parameter Formula First Sample Date Status
Light Scattering Coefficient σsp 1976-05-07 Ongoing
Light Absorption Coefficient σap 1988-01-01 Ongoing
Particle Number Concentration Nt 1976-05-07 Ongoing
Aerosol Chemical Composition 1998-01-01 Ongoing
Cloud condensation nucleus number concentration Nccn 2007-01-01 Ongoing
Aerosol Hygroscopic Growth f(RH) 2007-01-01 Ongoing
Aerosol Size Distribution n(D) 2007-01-01 Ongoing

Radiation In-Situ Observatory

Parameter Formula First Sample Date Status
Direct Normal 1976-03-01 Ongoing
Downwelling Shortwave 1976-03-01 Ongoing
Diffuse 1995-07-05 Ongoing
Upwelling Shortwave 1985-01-01 Ongoing
Downwelling Longwave 1993-04-20 Ongoing
Upwelling Longwave 1993-04-20 Ongoing
Spectral 2001-04-01 Ongoing

Surface Ozone

Parameter Formula First Sample Date Status
Ozone O3 1973-03-14 Ongoing

Dobson Total Ozone

Parameter Formula First Sample Date Status
Ozone O3 1973-07-29 Ongoing


Parameter Formula First Sample Date Status
Wind Speed ws 1973-02-17 Ongoing
Wind Direction wd 1973-02-17 Ongoing
Temperature temp 1976-01-01 Ongoing
Ambient Pressure press 1976-01-01 Ongoing
Relative Humidity rh 1976-01-01 Ongoing