GMD Site Description: SUM


  • Country: Greenland Country Flag
  • Latitude: 72.5962° North
  • Longitude: 38.422° West
  • Elevation: 3209.54 masl
  • Time Zone: Local Time + 2.0 hour(s) = UTC


Cooperating Agencies

The Greenland Environmental Observatory (GEOSummit) on the summit of the Greenland Ice Sheet (72°N, 38°W, 3200 m.a.s.l.) was established by the U.S. National Science Foundation (NSF) and the Danish Commission for Scientific Research in Greenland to provide year-round, long-term measurements for monitoring and investigations of the Arctic environment. The multidisciplinary facility is home to several year-round investigations as well as numerous seasonal campaigns which take advantage of the unique location of the observatory. GEOSummit provides investigators ease of access to the highest site north of the Arctic circle. Since 1989, when the GISP II ice-coring activities began, the site has hosted numerous atmospheric and glaciological investigations. Following two trial winter over periods (1997-1998, and 2000-2002), the NSF Long Term Observatory (LTO) program committed funding to maintain year-round measurements of key baseline variables of climate change at the site. In addition, several programs funded through European agencies have a year-round presence at the site.

The Summit website is at

GMD Projects at Summit

Carbon Cycle Surface Flasks

Parameter Formula First Sample Date Status
Carbon Dioxide CO2 1997-06-23 Ongoing
Methane CH4 1997-06-23 Ongoing
Carbon Monoxide CO 1997-06-23 Ongoing
Molecular Hydrogen H2 1997-06-23 Ongoing
Nitrous Oxide N2O 1997-06-23 Ongoing
Sulfur Hexafluoride SF6 1997-06-23 Ongoing
Carbon-13/Carbon-12 in Carbon Dioxide d13C (CO2) 1997-06-23 Ongoing
Oxygen-18/Oxygen-16 in Carbon Dioxide d18O (CO2) 1997-06-23 Ongoing
Carbon-13/Carbon-12 in Methane d13C (CH4) 2010-04-27 Ongoing
Methyl Chloride CH3Cl 2004-10-18 Ongoing
Benzene C6H6 2006-07-17 Ongoing
toluene C7H8 2006-07-17 Ongoing
ethane C2H6 2004-10-18 Ongoing
ethene C2H4 2004-10-18 Ongoing
propane C3H8 2004-10-18 Ongoing
propene C3H6 2004-10-18 Ongoing
i-butane i-C4H10 2004-10-18 Ongoing
n-butane n-C4H10 2004-10-18 Ongoing
i-pentane i-C5H12 2004-10-18 Ongoing
n-pentane n-C5H12 2004-10-18 Ongoing
n-hexane n-C6H14 2004-10-18 Ongoing
Wind Speed ws 1997-06-23 Ongoing
Wind Direction wd 1997-06-23 Ongoing
Temperature temp 2004-05-10 Terminated - 2004-08-09
isoprene C5H8 2006-07-17 Ongoing
Acetylene C2H2 2007-09-24 Ongoing

HATS Flask Sampling

Parameter Formula First Sample Date Status
HFC-134a CH2FCF3 2004-06-20 Ongoing
HCFC-22 CHF2Cl 2004-06-20 Ongoing
Methyl Chloride CH3Cl 2004-06-20 Ongoing
HCFC-142b CH3CF2Cl 2004-06-20 Ongoing
Halon-1211 CBrClF2 2004-06-20 Ongoing
methyl bromide CH3Br 2004-06-20 Ongoing
CFC-113 CCl2FCClF2 2004-06-20 Ongoing
dichloromethane CH2Cl2 2004-06-20 Ongoing
tetrachloroethylene C2Cl4 2009-03-10 Ongoing
carbonyl sulfide COS 2004-06-20 Ongoing
HFC-152a CH3CHF2 2004-06-20 Ongoing
Halon 2402 CBrF2CBrF2 2009-03-10 Ongoing
HFC-227ea CF3CHFCF3 2011-05-08 Ongoing
HFC-365mfc CH3CF2CH2CF3 2009-06-08 Ongoing
Methyl Chloroform CH3CCl3 2004-06-20 Ongoing

HATS In Situ Observatory

Parameter Formula First Sample Date Status
Nitrous Oxide N2O 2007-07-16 Ongoing
Sulfur Hexafluoride SF6 2007-07-16 Ongoing
CFC-12 CCl2F2 2007-07-20 Ongoing
Halon-1211 CBrClF2 2007-11-22 Ongoing
CFC-113 CCl2FCClF2 2007-07-20 Ongoing
carbon tetrachloride CCl4 2007-07-20 Ongoing
Methyl Chloroform CH3CCl3 2007-07-20 Ongoing
CFC-11 CCl3F 2007-07-20 Ongoing

Aerosol Surface In-Situ

Parameter Formula First Sample Date Status
Light Scattering Coefficient σsp 2011-01-10 Ongoing
Light Absorption Coefficient σap 2011-01-10 Ongoing
Particle Number Concentration Nt 2011-01-10 Ongoing

Radiation In-Situ Observatory

Parameter Formula First Sample Date Status
Direct Beam 2006-05-28 Ongoing
Shortwave Global 2006-05-28 Ongoing
Diffuse 2006-05-28 Ongoing
Reflected Shortwave 2006-05-28 Ongoing
Downward Longwave 2006-05-28 Ongoing
Upward Longwave 2006-05-28 Ongoing

Surface Ozone

Parameter Formula First Sample Date Status
Ozone O3 2000-06-01 Ongoing




Parameter Formula First Sample Date Status
Wind Speed ws 2008-06-25 Ongoing
Wind Direction wd 2008-06-25 Ongoing
Temperature temp 2008-06-26 Ongoing
Ambient Pressure press 2008-06-25 Ongoing
Relative Humidity rh 2008-08-15 Ongoing

Black Carbon