Seasonal cycle and secular trend of the total and tropospheric column abundance of ethane above the Jungfraujoch

Journal Article · Wed Mar 20 00:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JD02229· OSTI ID:5331333

Ehhalt, D H; Schmidt, U ^[1]; Zander, R; Demoulin, P ^[2]; Rinsland, C P ^[3]

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1. Inst. fuer Atmosphaerische Chemie, Juelich (West Germany)
2. Univ. of Liege (Belgium)
3. NASA Langley Research Center, Hampton, VA (USA)

Total column abundances of ethane (C{sub 2}H{sub 6}) above the Jungfraujoch Station, Switzerland, 3.58-km altitude, have been deduced from infrared solar spectra recorded in 1951 and from 1984 to 1988. The results were derived from the spectroscopic analysis of the v{sub 7} band P{sub Q3}, and R{sub Q0} subbranches of C{sub 2}H{sub 6} near 2976.8, 2983.4, and 2986.7 cm{sup {minus}1} , respectively. The 1984-1988 results obtained from more than 300 observations at 0.005 cm{sup {minus}1} resolution show a definite seasonal variation in the total vertical column abundance of that gas, with a maximum of (1.43 {plus minus} 0.03) {times} 10{sup 16} molecules/cm{sup 2} during March and April and a minimum in the fall. The corresponding C{sub 2}H{sub 6} mixing ratio in the free troposphere was derived to 1.53 {plus minus} 0.14 ppb in early April; the ratio of maximum to minimun C{sub 2}H{sub 6} concentration in the troposphere was found to be 1.88 {plus minus} 0.12. From the analysis of the same spectral features observed in March and April 1951, the authors have deduced a total vertical column abundance of (1.09 {plus minus} 0.10) {times} 10{sup 16} molecules/cm{sup 2}. Assuming an exponential increase with time and correcting for a small decrease in the stratospheric amount of C{sub 2}H{sub 6} due to the man-induced increase in stratospheric chlorine, they obtain a secular trend in the tropospheric burden above the Jungfraujoch equal to (0.85 {plus minus} 0.3)% yr{sup {minus}1}. It is argued that this trend is valid for the entire northern hemisphere.

• OSTI ID: 5331333
• Journal Information: Journal of Geophysical Research; (United States), Vol. 96:D3; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ETHANE
ECOLOGICAL CONCENTRATION
SWITZERLAND
AIR POLLUTION
TROPOSPHERE
ATMOSPHERIC CHEMISTRY
BIOMASS
COMBUSTION
FOSSIL FUELS
HYDROXYL RADICALS
INFRARED SPECTRA
NORTHERN HEMISPHERE
SEASONAL VARIATIONS
ALKANES
CHEMICAL REACTIONS
CHEMISTRY
DEVELOPED COUNTRIES
EARTH ATMOSPHERE
EARTH PLANET
ENERGY SOURCES
EUROPE
FUELS
HYDROCARBONS
ORGANIC COMPOUNDS
OXIDATION
PLANETS
POLLUTION
RADICALS
RENEWABLE ENERGY SOURCES
SPECTRA
THERMOCHEMICAL PROCESSES
VARIATIONS
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)