Mixing ratios of carbon monoxide in the troposphere

Journal Article · Sun Dec 20 04:00:00 EST 1992 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/92JD02010· OSTI ID:6755201

Novelli, P C; Steele, L P ^[1]; Tans, P P ^[2]

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1. Univ. of Colorado, Boulder (United States)
2. NOAA, Boulder, CO (United States)

Carbon monoxide (CO) mixing ratios were measured in air samples collected weekly at eight locations. The air was collected as part of the CMDL/NOAA cooperative flask sampling program (Climate Monitoring and Diagnostics Laboratory, formerly Geophysical Monitoring for Climatic Change, Air Resources Laboratory/National Oceanic and Atmospheric Administration) at Point Barrow, Alaska, Niwot Ridge, Colorado, Mauna Loa and Cape Kumakahi, Hawaii, Guam, Marianas Islands, Christmas Island, Ascension Island and American Samoa. Half-liter or 3-L glass flasks fitted with glass piston stopcocks holding teflon O rings were used for sample collection. CO levels were determined within several weeks of collection using gas chromatography followed by mercuric oxide reduction detection, and mixing ratios were referenced against the CMDL/NOAA carbon monoxide standard scale. During the period of study (mid-1988 through December 1990) CO levels were greatest in the high latitudes of the northern hemisphere (mean mixing ratio from January 1989 to December 1990 at Point Barrow was approximately 154 ppb) and decreased towards the south (mean mixing ratio at Samoa over a similar period was 65 ppb). Mixing ratios varied seasonally, the amplitude of the seasonal cycle was greatest in the north and decreased to the south. Carbon monoxide levels were affected by both local and regional scale processes. The difference in CO levels between northern and southern latitudes also varied seasonally. The greatest difference in CO mixing ratios between Barrow and Samoa was observed during the northern winter (about 150 ppb). The smallest difference, 40 ppb, occurred during the austral winter. The annually averaged CO difference between 71[degrees]N and 14[degrees]S was approximately 90 ppb in both 1989 and 1990; the annually averaged interhemispheric gradient from 71[degrees]N to 41[degrees]S is estimated as approximately 95 ppb. 66 refs., 5 figs., 5 tabs.

• OSTI ID: 6755201
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 97:D18; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHROMATOGRAPHY
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
GAS CHROMATOGRAPHY
GREENHOUSE GASES
OXIDES
OXYGEN COMPOUNDS
SAMPLING
SEASONAL VARIATIONS
SEPARATION PROCESSES
TROPOSPHERE
VARIATIONS