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Mauna Loa, Hawaii, United States [MLO]


  • Country: United States Country Flag
  • Latitude: 19.5362° North
  • Longitude: 155.5763° West
  • Elevation: 3397.00 masl
  • Time Zone: Local Standard Time + 10.0 hour(s) = UTC


  • Address: NOAA - Mauna Loa Observatory
    1437 Kilauea Ave. #102
    Hilo, Hawaii, 96720, United States
  • Phone: (808)933-6965 Ext. 237
  • Fax: (808)933-6967


Mauna Loa Observatory is located on the Island of Hawaii at an elevation of 3397 m on the northern flank of Mauna Loa volcano at 200 north. Established in 1957, Mauna Loa Observatory has grown to become the premier long-term atmospheric monitoring facility on earth and is the site where the ever-increasing concentrations of global atmospheric carbon dioxide were determined. The observatory consists of 10 buildings from which up to 250 different atmospheric parameters are measured by a complement of 12 NOAA/ESRL and other agency scientists and engineers.

GMD Projects at Mauna Loa, Hawaii

Carbon Cycle Surface Flasks

Parameter Formula First Sample Date Status
Carbon Dioxide CO2 1969-08-20 Ongoing
Methane CH4 1983-05-06 Ongoing
Carbon Monoxide CO 1989-07-07 Ongoing
Molecular Hydrogen H2 1989-07-07 Ongoing
Nitrous Oxide N2O 1995-12-15 Ongoing
Sulfur Hexafluoride SF6 1995-12-15 Ongoing
Carbon-13/Carbon-12 in Carbon Dioxide d13C (CO2) 1990-01-12 Ongoing
Oxygen-18/Oxygen-16 in Carbon Dioxide d18O (CO2) 1990-01-12 Ongoing
Carbon-13/Carbon-12 in Methane d13C (CH4) 1998-01-02 Ongoing
D/H in Methane dD (CH4) 2005-04-06 Terminated - 2009-11-03
Methyl Chloride CH3Cl 2005-05-11 Ongoing
Benzene C6H6 2006-12-13 Ongoing
toluene C7H8 2006-12-13 Ongoing
ethane C2H6 2005-05-11 Ongoing
ethene C2H4 2005-05-11 Ongoing
propane C3H8 2005-05-11 Ongoing
propene C3H6 2005-05-11 Ongoing
i-butane i-C4H10 2005-05-11 Ongoing
n-butane n-C4H10 2005-05-11 Ongoing
i-pentane i-C5H12 2005-05-11 Ongoing
n-pentane n-C5H12 2005-05-11 Ongoing
n-hexane n-C6H14 2005-05-11 Ongoing
isoprene C5H8 2006-12-13 Ongoing
Acetylene C2H2 2006-12-13 Ongoing

Carbon Cycle In Situ Observatory

Parameter Formula First Sample Date Status
Carbon Dioxide CO2 1974-05-17 Ongoing
Methane CH4 1987-04-03 Ongoing
Carbon Monoxide CO 1992-05-29 Ongoing

HATS Flask Sampling

Parameter Formula First Sample Date Status
HFC-134a CH2FCF3 1994-11-07 Ongoing
HCFC-22 CHF2Cl 1991-12-30 Ongoing
CFC-12 CCl2F2 2010-01-05 Ongoing
Methyl Chloride CH3Cl 1993-08-30 Ongoing
HCFC-142b CH3CF2Cl 1992-02-10 Ongoing
Halon-1211 CBrClF2 1991-12-30 Ongoing
methyl bromide CH3Br 1993-08-30 Ongoing
HCFC-141b CH3CCl2F 1992-12-28 Ongoing
CFC-113 CCl2FCClF2 1991-12-30 Ongoing
dichloromethane CH2Cl2 1994-01-18 Ongoing
tetrachloroethylene C2Cl4 1993-11-22 Ongoing
carbonyl sulfide COS 2000-03-13 Ongoing
HFC-152a CH3CHF2 2000-08-14 Ongoing
Halon 1301 CF3Br 2004-03-08 Ongoing
Halon 2402 CBrF2CBrF2 1995-03-13 Ongoing
HFC-143a CH3CF3 2006-12-27 Ongoing
HFC-227ea CF3CHFCF3 2011-06-14 Ongoing
HFC-365mfc CH3CF2CH2CF3 2009-08-13 Ongoing
HFC-125 CHF2CF3 2006-12-27 Ongoing
HFC-32 CH2F2 2009-03-12 Ongoing
Methyl Chloroform CH3CCl3 1991-12-30 Ongoing
CFC-11 CCl3F 2010-01-05 Ongoing

HATS In Situ Observatory

Parameter Formula First Sample Date Status
Nitrous Oxide N2O 1999-07-08 Ongoing
Sulfur Hexafluoride SF6 1999-06-25 Ongoing
HCFC-22 CHF2Cl 1998-11-28 Ongoing
CFC-12 CCl2F2 1999-06-25 Ongoing
Methyl Chloride CH3Cl 1999-04-23 Ongoing
HCFC-142b CH3CF2Cl 1999-01-01 Ongoing
Halon-1211 CBrClF2 1998-12-03 Ongoing
CFC-113 CCl2FCClF2 1999-12-14 Ongoing
chloroform CHCl3 1998-09-01 Ongoing
carbon tetrachloride CCl4 1999-06-25 Ongoing
Methyl Chloroform CH3CCl3 1999-04-23 Ongoing
CFC-11 CCl3F 1999-06-25 Ongoing

Aerosol Surface In-Situ

Parameter Formula First Sample Date Status
Light Scattering Coefficient σsp 1974-01-01 Ongoing
Light Absorption Coefficient σap 1990-01-01 Ongoing
Particle Number Concentration Nt 1974-01-01 Ongoing

Radiation In-Situ Observatory

Parameter Formula First Sample Date Status
Direct Normal 1976-03-01 Ongoing
Downwelling Shortwave 1976-03-01 Ongoing
Diffuse 1976-03-01 Ongoing
Downwelling Longwave 1993-10-31 Ongoing
Spectral 2001-07-01 Ongoing

Surface Ozone

Parameter Formula First Sample Date Status
Ozone O3 1973-09-20 Ongoing

Dobson Total Ozone

Parameter Formula First Sample Date Status
Ozone O3 1963-12-26 Ongoing


Parameter Formula First Sample Date Status
Aerosol backscatter (694 nm) 1974-12-03 Terminated - 1998-10-27
Aerosol backscatter (532 nm) 1994-04-04 Ongoing
Aerosol backscatter (1064 nm) 2001-01-05 Ongoing
Water vapor density 2005-10-26 Ongoing


Parameter Formula First Sample Date Status
Wind Speed ws 1977-01-01 Ongoing
Wind Direction wd 1977-01-01 Ongoing
Temperature temp 1977-01-01 Ongoing
Ambient Pressure press 1977-01-01 Ongoing
Relative Humidity rh 1977-01-01 Ongoing

Dobson Umkehr Ozone

Parameter Formula First Sample Date Status
Ozone O3 1963-12-26 Ongoing

Spectral UV Irradiance