Surface ozone pattern and budget in Hong Kong

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:466110

Chan, L Y; Chan, C Y; Quin, Y; Lam, K S; Wang, T ^[1]

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1. Hong Kong Polytechnic Univ. (Hong Kong)

Surface ozone, its precursors and meteorology measurement from 1990 to 1994 in Hong Kong are presented in this paper. A unique ozone seasonal variation with autumn peak and summer trough and other seasons being the transition period is observed and the absence of the usual observed spring peak is found to be associated with the Asian monsoon system, which brings different air masses into the territories. The absence of spring and summer peaks suggested that the stratospheric incursion and local photochemical production are of secondary important. Examination of the correlation analyses results suggest that the relative strong wind induced sufficient ventilation effect leading to less accumulation of ozone precursors and thus lowers the local photochemical production and destruction in the territories. The rural ozone concentration (17-48 ppb) shows that the background ozone is the dominant source in Hong Kong and the urban areas are acting as a net sink of the natural ozone due to the filtration effect of the precursor emissions. Among the different precursor emissions, vehicle emission together with the local topography are found to be the main factors contributing to the spatial ozone distribution in the territories. It is shown that the spatial, diurnal and seasonal variation of surface ozone concentration level follows the null cycle between NO and NO{sub 2} and that the surface ozone budget in the territories is governed by the photochemical equilibrium state as indicated by the NO{sub 2}/NO ratio.

• OSTI ID: 466110
• Report Number(s): CONF-9606185--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
ECOLOGICAL CONCENTRATION
HONG KONG
OZONE
SEASONAL VARIATIONS
SPATIAL DISTRIBUTION