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Observation Sites
Niwot Ridge, Colorado, United States [NWR]

Location
- Country: United States
- Latitude: 40.0531° North
- Longitude: 105.5864° West
- Elevation: 3523.00 masl
- Time Zone: Local Standard Time + 7.0 hour(s) = UTC
Data
Cooperating Agencies
Niwot Ridge is located approximately 35 km west of Boulder, Colorado, with the entire study site lying above 3000 m elevation. There is a cirque glacier (Arikaree Glacier), extensive alpine tundra, a variety of glacial landforms, glacial lakes and moraines, cirques and talus slopes, patterned ground, and permafrost. The research area is bounded on the west by the Continental Divide, with runoff on the two sides being destined for the Colorado and Mississippi Rivers. The alpine study area is reached by an unimproved road from the Mountain Research Station (2895 m) which leads to within 2 km of the main tundra research site, the Saddle (3528 m). Niwot Ridge, including the main alpine study site, is part of the Roosevelt National Forest and has been designated a Biosphere Reserve (United Nations Educational, Scientific and Cultural Organization, UNESCO) and an Experimental Ecology Reserve (USDA Forest Service).
Parameter | Formula | First Sample Date | Status |
---|---|---|---|
Carbon Dioxide | CO2 | 1967-05-18 | Ongoing |
Carbon Dioxide | CO2 | 2005-09-16 | Ongoing |
Methane | CH4 | 1983-05-11 | Ongoing |
Methane | CH4 | 2005-09-16 | Ongoing |
Carbon Monoxide | CO | 1988-12-13 | Ongoing |
Carbon Monoxide | CO | 2005-09-16 | Ongoing |
Molecular Hydrogen | H2 | 2005-09-16 | Ongoing |
Molecular Hydrogen | H2 | 1988-12-27 | Ongoing |
Nitrous Oxide | N2O | 2005-09-16 | Ongoing |
Nitrous Oxide | N2O | 1997-04-22 | Ongoing |
Sulfur Hexafluoride | SF6 | 2014-12-23 | Ongoing |
Sulfur Hexafluoride | SF6 | 2005-09-16 | Ongoing |
Sulfur Hexafluoride | SF6 | 1997-04-22 | Ongoing |
Carbon-13/Carbon-12 in Carbon Dioxide | d13C (CO2) | 2005-09-16 | Ongoing |
Carbon-13/Carbon-12 in Carbon Dioxide | d13C (CO2) | 1990-01-09 | Ongoing |
Oxygen-18/Oxygen-16 in Carbon Dioxide | d18O (CO2) | 1990-01-09 | Ongoing |
Oxygen-18/Oxygen-16 in Carbon Dioxide | d18O (CO2) | 2005-09-16 | Ongoing |
Carbon-13/Carbon-12 in Methane | d13C (CH4) | 1998-01-06 | Ongoing |
Carbon-14/Carbon in Carbon Dioxide | D14C (CO2) | 2003-05-27 | Ongoing |
D/H in Methane | dD (CH4) | 2005-05-24 | Terminated - 2010-01-26 |
HFC-134a | CH2FCF3 | 2012-04-10 | Ongoing |
HCFC-22 | CHF2Cl | 2012-04-10 | Ongoing |
CFC-12 | CCl2F2 | 2012-04-10 | Ongoing |
Methyl Chloride | CH3Cl | 2015-02-24 | Terminated - 2018-05-29 |
Methyl Chloride | CH3Cl | 2012-04-10 | Ongoing |
Methyl Chloride | CH3Cl | 2005-12-06 | Terminated - 2014-11-11 |
CFC-114 | CFC-114 | 2012-04-10 | Ongoing |
HCFC-142b | CH3CF2Cl | 2012-04-10 | Ongoing |
Halon-1211 | CBrClF2 | 2012-04-10 | Ongoing |
Methyl Bromide | CH3Br | 2012-04-10 | Ongoing |
CFC-11 | CCl3F (ion 101) | 2012-04-10 | Terminated - 2015-11-15 |
CFC-11 | CCl3F (ion 103) | 2014-12-23 | Ongoing |
HCFC-141b | CH3CCl2F | 2012-04-10 | Ongoing |
Methyl Iodide | CH3I | 2012-04-10 | Ongoing |
CFC-113 | CCl2FCClF2 | 2012-04-10 | Ongoing |
Dichloromethane | CH2Cl2 | 2012-04-10 | Ongoing |
Chloroform | CHCl3 | 2012-04-10 | Ongoing |
Methyl Chloroform | CH3CCl3 | 2012-04-10 | Ongoing |
Carbon Tetrachloride | CCl4 | 2012-04-10 | Ongoing |
Dibromomethane | CH2Br2 | 2012-04-10 | Ongoing |
Perchloroethylene (PCE) | C2Cl4 | 2012-04-10 | Ongoing |
Bromoform | CHBr3 | 2012-04-10 | Ongoing |
Benzene | C6H6 | 2012-04-10 | Ongoing |
Benzene | C6H6 | 2010-01-19 | Terminated - 2014-11-11 |
Benzene | C6H6 | 2015-02-24 | Terminated - 2018-05-29 |
Carbonyl Sulfide | COS | 2012-04-10 | Ongoing |
HCFC-21 | CHCl2F | 2015-06-15 | Ongoing |
HFC-152a | CH3CHF2 | 2012-04-10 | Ongoing |
HCFC-124 | CHClFCF3 | 2012-04-10 | Ongoing |
Toluene | C7H8 | 2015-02-24 | Terminated - 2018-05-29 |
Toluene | C7H8 | 2010-01-19 | Terminated - 2014-11-11 |
Toluene | C7H8 | 2014-12-23 | Ongoing |
Carbon Disulfide | CS2 | 2012-04-10 | Ongoing |
Ethane | C2H6 | 2014-12-23 | Ongoing |
Ethane | C2H6 | 2015-02-24 | Terminated - 2018-05-29 |
Ethane | C2H6 | 2005-12-06 | Terminated - 2014-11-11 |
Ethene | C2H4 | 2015-02-24 | Terminated - 2018-05-29 |
Ethene | C2H4 | 2005-12-06 | Terminated - 2014-11-11 |
Ethene | C2H4 | 2014-12-23 | Ongoing |
Propane | C3H8 | 2015-02-24 | Terminated - 2018-05-29 |
Propane | C3H8 | 2012-04-10 | Ongoing |
Propane | C3H8 | 2005-12-06 | Terminated - 2014-11-11 |
Propene | C3H6 | 2014-12-23 | Ongoing |
Propene | C3H6 | 2005-12-06 | Terminated - 2014-11-11 |
Propene | C3H6 | 2015-02-24 | Terminated - 2018-05-29 |
i-Butane | i-C4H10 | 2005-12-06 | Terminated - 2014-11-11 |
i-Butane | i-C4H10 | 2015-02-24 | Terminated - 2018-05-29 |
i-Butane | i-C4H10 | 2014-12-23 | Ongoing |
n-Butane | n-C4H10 | 2005-12-06 | Terminated - 2014-11-11 |
n-Butane | n-C4H10 | 2012-04-10 | Ongoing |
n-Butane | n-C4H10 | 2015-02-24 | Terminated - 2018-05-29 |
i-Pentane | i-C5H12 | 2005-12-06 | Terminated - 2014-11-11 |
i-Pentane | i-C5H12 | 2015-02-24 | Terminated - 2018-05-29 |
i-Pentane | i-C5H12 | 2012-04-10 | Ongoing |
n-Pentane | n-C5H12 | 2012-04-10 | Ongoing |
n-Pentane | n-C5H12 | 2005-12-06 | Terminated - 2014-11-11 |
n-Pentane | n-C5H12 | 2015-02-24 | Terminated - 2018-05-29 |
n-Hexane | n-C6H14 | 2015-02-24 | Terminated - 2018-05-29 |
n-Hexane | n-C6H14 | 2005-12-06 | Terminated - 2014-11-11 |
n-Hexane | n-C6H14 | 2014-12-23 | Ongoing |
Ambient Pressure | press | 2006-12-14 | Terminated - 2018-11-04 |
Relative Humidity | rh | 2006-12-14 | Terminated - 2017-06-01 |
isoprene | C5H8 | 2010-01-19 | Terminated - 2014-11-11 |
isoprene | C5H8 | 2015-02-24 | Terminated - 2018-05-29 |
Halon-1301 | CF3Br | 2012-04-10 | Ongoing |
Halon-2402 | CBrF2CBrF2 | 2012-04-10 | Ongoing |
HFC-143a | CH3CF3 | 2012-04-10 | Ongoing |
HFC-227ea | CF3CHFCF3 | 2012-04-10 | Ongoing |
HFC-365mfc | CH3CF2CH2CF3 | 2012-04-10 | Ongoing |
CFC-115 | CClF2CF3 | 2012-04-10 | Ongoing |
HFC-125 | CHF2CF3 | 2012-04-10 | Ongoing |
CFC-13 | CClF3 | 2012-04-10 | Ongoing |
Ethyl Chloride | CH3CH2Cl | 2012-04-10 | Terminated - 2014-07-23 |
HFC-23 | CHF3 | 2012-04-10 | Ongoing |
PFC-218 | C3F8 | 2012-04-10 | Ongoing |
Acetylene | C2H2 | 2010-01-19 | Terminated - 2014-11-11 |
Acetylene | C2H2 | 2015-02-24 | Terminated - 2018-05-29 |
Acetylene | C2H2 | 2012-04-10 | Ongoing |
HFC-32 | CH2F2 | 2012-04-10 | Ongoing |
HFC-134 | CHF2CHF2 | 2012-04-10 | Ongoing |
Halon-1011 | CH2BrCl | 2014-12-23 | Ongoing |
PFC-14 | CF4 | 2014-12-23 | Ongoing |
PFC-116 | CF3CF3 | 2014-12-23 | Ongoing |
Nitrogen Trifluoride | NF3 | 2015-05-19 | Ongoing |
Sulfuryl Fluoride | SO2F2 | 2015-05-19 | Ongoing |
HFC-236fa | CF3CH2CF3 | 2014-12-23 | Ongoing |
HCFC-133a | CH2ClCF3 | 2014-12-23 | Ongoing |
CFC-112 | CCl3CClF2 | 2014-12-23 | Ongoing |
Trichloroethylene (TCE) | C2HCl3 | 2014-12-23 | Ongoing |
HFO-1234yf | CH2=CFCF3 | 2016-06-14 | Ongoing |
HFO-1234zeE | CHF=CHCF3 | 2016-06-14 | Ongoing |
Ethylene Dichloride (1,2 DCE) | CH2ClCH2Cl | 2017-12-04 | Ongoing |
HCFC-123 | CHCl2CF3 | 2017-12-04 | Ongoing |
Morpholine | C5F11NO | 2017-11-21 | Ongoing |
Perfluorotriethylamine (PFTEA) | (C2F5)3N | 2017-11-21 | Ongoing |
Perfluorotripropylamine (PFTPA) | (C3F7)3N | 2017-11-21 | Ongoing |
HFC-245fa | 2022-05-26 | Ongoing |
Parameter | Formula | First Sample Date | Status |
---|---|---|---|
HFC-134a | CH2FCF3 | 1994-12-13 | Ongoing |
HCFC-22 | CHF2Cl | 1991-12-24 | Ongoing |
CFC-12 | CCl2F2 | 2010-01-05 | Ongoing |
Methyl Chloride | CH3Cl | 1995-02-14 | Ongoing |
HCFC-142b | CH3CF2Cl | 1992-02-18 | Ongoing |
Halon-1211 | CBrClF2 | 1991-12-24 | Ongoing |
Methyl Bromide | CH3Br | 1993-09-28 | Ongoing |
HCFC-141b | CH3CCl2F | 1992-12-15 | Ongoing |
CFC-113 | CCl2FCClF2 | 1991-12-24 | Ongoing |
Dichloromethane | CH2Cl2 | 1995-04-04 | Ongoing |
Perchloroethylene (PCE) | C2Cl4 | 1993-12-07 | Ongoing |
Carbonyl Sulfide | COS | 2000-03-14 | Ongoing |
HFC-152a | CH3CHF2 | 2000-08-01 | Ongoing |
Halon-2402 | CBrF2CBrF2 | 1995-02-14 | Ongoing |
HFC-227ea | CF3CHFCF3 | 2011-06-07 | Ongoing |
HFC-365mfc | CH3CF2CH2CF3 | 2009-08-04 | Ongoing |
Methyl Chloroform | CH3CCl3 | 1991-12-24 | Ongoing |
CFC-11 | CCl3F | 2010-01-05 | Ongoing |
Parameter | Formula | First Sample Date | Status |
---|---|---|---|
Nitrous Oxide | N2O | 2001-01-08 | Ongoing |
Sulfur Hexafluoride | SF6 | 2001-01-08 | Ongoing |
HCFC-22 | CHF2Cl | 2000-12-22 | Ongoing |
CFC-12 | CCl2F2 | 2001-06-14 | Ongoing |
Methyl Chloride | CH3Cl | 2000-11-09 | Ongoing |
HCFC-142b | CH3CF2Cl | 2001-06-15 | Ongoing |
Halon-1211 | CBrClF2 | 2000-11-08 | Ongoing |
CFC-113 | CCl2FCClF2 | 2001-05-05 | Ongoing |
Carbon Tetrachloride | CCl4 | 2001-05-01 | Ongoing |
Methyl Chloroform | CH3CCl3 | 2001-05-01 | Ongoing |
CFC-11 | CCl3F | 2001-05-01 | Ongoing |
Parameter | Formula | First Sample Date | Status |
---|---|---|---|
Ozone | O3 | 1990-07-26 | Ongoing |
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