OZONE CONCENTRATION CHARACTERISTICS AT A HIGH-ELEVATION FOREST SITE

Citation
G. Wooldridge et al., OZONE CONCENTRATION CHARACTERISTICS AT A HIGH-ELEVATION FOREST SITE, Theoretical and applied climatology, 56(3-4), 1997, pp. 153-164
Citations number
24
Categorie Soggetti
Metereology & Atmospheric Sciences
ISSN journal
0177798X
Volume
56
Issue
3-4
Year of publication
1997
Pages
153 - 164
Database
ISI
SICI code
0177-798X(1997)56:3-4<153:OCCAAH>2.0.ZU;2-F
Abstract
Atmospheric ozone concentrations have been monitored at a subalpine fo rest ecosystem site, 3180 m above mean sea level (msl), and at a 2680 m msl forest-steppe ecotone site 15 km to the southeast. Ozone concent rations were monitored at three heights above the ground on a 30 m tow er al the higher elevation site, and on a 10 m tower in a large meadow downwind of this site. The research reported here concentrates on the data for the first six months of 1990-1994. The diel amplitude of ozo ne concentrations is very small in winter, increasing as the seasons a dvance to June. Following snowmelt in late May or June. the nighttime minima decrease under the forest canopy. The highest monthly mean ozon e concentrations occur in April or May, depending on the year. Episoda l high concentrations were recorded during spring months when upper le vel atmospheric low pressure troughs and cut-off low centers occurred. These contributions peak in May, and add about 10% to normal May back ground ozone concentrations. varying widely from year to year. Spectra l representations of ozone concentrations, illustrate the suppression of the diel peak during spring months, when stratospheric-tropospheric intrusion patterns show no significant diel cycle.