Tropospheric chemistry over the lower Great Plains of the United States. 2. Trace gas profiles and distributions

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

DOI:https://doi.org/10.1029/92JD02127· OSTI ID:7025889

Luke, W T; Dickerson, R R; Ryan, W F; Pickering, K E; Nunnermacker, L J ^[1]

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1. Univ. of Maryland, College Park (United States)

Convective clouds and thunderstorms redistribute air pollutants vertically, and by altering the chemistry and radiative balance of the upper troposphere, these local actions can have global consequences. To study these effects, measurements of trace gases ozone, O[sub 3], carbon monoxide, CO, and odd nitrogen were made aboard the NCAR Sabreliner on 18 flights over the southern Great Plains during June 1985. To demonstrate chemical changes induced by vertical motions in the atmosphere and to facilitate comparison with computer model calculations, these data were categorized according to synoptic flow patterns. Part 1 of this two-part paper details the alternating pulses of polar and maritime air masses that dominate the vertical mixing in this region. In this paper, trace gas measurements are presented as altitude profiles (0-12 km) with statisitcal distributions of mixing ratios for each species in each flow pattern. The polar flow regime is characterized by northwesterly winds, subsiding air, and convective stability. The maritime regime is characterized by southerly surface winds, convective instability, and a deep planetary boundary layer PBL; uniformly high concentrations of trace gases were found up to 4 km on one flight. During frontal passage both stratiform and convective clouds mix pollutants more uniformly into the middle and upper levels; high mixing ratios of CO are found at all altitudes, and O[sub 3] levels are highest of any category, implicating photochemical production. These results illustrate the importance of convection in tropospheric chemistry. Use of average trace gas profiles or eddy diffusion parameterized vertical mixing can lead to errors of 30 to 50% in O[sub 3] and CO concentrations and an order of magnitude for odd nitrogen. 80 refs., 18 figs., 9 tabs.

• OSTI ID: 7025889
• 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

29 ENERGY PLANNING, POLICY, AND ECONOMY
290301 -- Energy Planning & Policy-- Environment
Health
& Safety-- Regional & Global Environmental Aspects-- (1992-)
54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION
ATMOSPHERIC CHEMISTRY
ATMOSPHERIC CIRCULATION
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMISTRY
CLIMATE MODELS
CLOUDS
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
GREAT PLAINS
MASS TRANSFER
MATHEMATICAL MODELS
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
OZONE
PHOTOCHEMISTRY
POLLUTION
TROPOSPHERE