• Journal of the Korean earth science society
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• v.26 no.3
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• pp.283-296
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• 2005

The effect of ozone and surface temperature on the ozone band at $9.7{\mu}m$ has been investigated from radiative transfer theory together with observations in order to derive empirical methods for remotely sensing ground-ozone concentration. Simultaneous observations of satellite (MODIS Aqua; ECT 13:30) and ground-ozone at 79 stations have been used over the Seoul Metropolitan Area (SMA; 125.7-127.2 E, 37.2-37.7 N) during four ozone-warning days in the year 2003. Cloud effect on the band in the methods was filtered out based on synoptic observations. Upwelling radiance values at $9.6{\mu}m$ which have been estimated at the given ozone concentration of 327-391 DU depend on surface temperature (Ts) showing $5.52\~5.78Wm^{-2}sr^{-1}\;at\;Ts = 290 K,\;and\;9.00\~9.57Wm^{-2}sr^{-1}$ Ts = 325K. Thus, the partitioned contributions of ozone and temperature to intensity of ozone absorption band are $0.26Wm^{-1}sr^{-1}/64\;DU\;and\;0.31 Wm^{-2}sr^{-1}/35K$, respectively. Here the intensity which has been used to remotely detect ground-ozone concentration from infrared satellite measurement is defined as the difference in brightness temperature between $11{\mu} m\;and\;9.7{\mu}m (i.e.,\; T_{11-9.7})$. The methods in this study have been applied to estimate ground-ozone from MODIS data in cases that there are significant correlations between the band intensity and ground-ozone. The values of estimated ozone significantly correlate (0.49-0.63) with ground observations at a significance level of $1\%$. For the improved methods, further study may be required to use tropospheric ozone rather than ground-ozone, considering the variation stratospheric ozone.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.32-36
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• 2004

본 연구는 최근 인구와 산업체가 급증하고 있는 김해시를 대상으로 김해시.군을 통합한 1996년 이후부터 2002년까지 김해시 지상오존농도의 변화경향과 고농도 오존일에 대한 사례 연구결과 다음과 같다. 김해시 대기오염농도의 시계열변화는 증가추세가 뚜렷하였으며, 최근 대기환경기준이 강화되면서 환경지정기준을 초과하기도 하였다. 계절별 오존농도의 일변화는 사계절 가운데 봄철이 가장 농도가 높게 나타났으며 매년 증가하는 농도폭도 가장 크게 나타났다. 이는 여름철의 경우 태양고도가 높고 단위시간당 일사량은 많으나, 장마와 같은 운량 증가로 인한 일사량의 감소되거나, 기온이 상승할 경우 해안으로부터 해풍이 증가하여 여름보다는 봄철에 더 높은 농도를 나타낸 것으로 생각되며, 인구와 자동차 등의 증가로 인한 배출량이 증가한 것도 크게 영향을 미친 것으로 생각된다. 연구기간동안 60 ppb 이상의 고농도 오존일의 총 발생빈도는 237일로 나타났으며, 매년 발생빈도가 증가하고 있으며, 대기환경기준 100 ppb/hr를 초과한 날도 8일이나 되었는데, 1999년이 4일 발생하여 오존에 의한 대기오염규제지역으로 선정되었는데, 고농도 오존일은 지난 1997년 이후 매년 증가하고 있으며 겨울을 제외한 전 월에 발생하는 특징을 나타내어 오존의 저감을 위한 실천 계획 수립뿐 아니라 고농도 오존일에 대한 집중적인 연구와 빠른 시간 내에 오존의 예.경보제를 도입 운영하는 것이 김해시민의 건강과 복지에 도움이 될 것으로 생각된다. 고농도 오존일에 대한 사례일 첫 번째인 5월 1일은 일 최고 기온은 그리 높은 상태는 아니었지만 광범위한 이동성 고기압에 의해 대기가 정체하고 바람이 약한 시점에 광화학반응에 의한 오존생성이 용이하였고 해안가의 높은 농도의 오존이 수송되어 고농도 오존이 발생하였으며, 사례 2의 경우 대륙에서 이동해 오는 이동성 고기압의 영향으로 대기는 안정하고 바람이 약하여 기온이 급상승하였으며, 광화학반응에 의한 오존 생성이 용이하였다. 사례 3의 경우는 남북으로 놓여 있는 대규모 기압계 사이에 안상부 형태의 대상고기압이 놓여 대기는 매우 안정하고 바람이 약하며 때때로 기압계에 의한 바람이 불 경우 다소 강한 바람이 불어 일사량이 많은 기압계에서 광화학반응과 수소에 의한 오존생성이 용이하여 고농도 오존을 발생하였다.

• Journal of the Korean earth science society
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• v.21 no.3
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• pp.287-301
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• 2000

In order to investigate the factors and processes affecting the vertical distributions of ozone, we analyzed the ozone profile data measured using ozonesonde from 1995 to 1997 at Pohang city, Korea. In the course of our study, we analyzed temporal and spatial distribution characteristics of ozone at four different heights: surface (100m), troposphere (10km), lower stratosphere (20km), and middle stratosphere (30km). Despite its proximity to a local, but major, industrial complex known as Pohang Iron and Steel Co. (POSCO), the concentrations of surface ozone in the study area were comparable to those typically observed from rural and/or unpolluted area. In addition, the findings of relative enhancement of ozone at this height, especially between spring and summer may be accounted for by the prevalence of photochemical reactions during that period of year. The temporal distribution patterns for both 10 and 20km heights were quite compatible despite large differences in their altitudes with such consistency as spring maxima and summer minima. Explanations for these phenomena may be sought by the mixed effects of various processes including: ozone transport across two heights, photochemical reaction, the formation of inversion layer, and so on. However, the temporal distribution pattern for the middle stratosphere (30km) was rather comparable to that of the surface. We also evaluated total ozone concentration of the study area using Brewer spectrophotometer. The total ozone concentration data were compared with those derived by combining the data representing stratospheric layers via Umkehr method. The results of correlation analysis showed that total ozone is negatively correlated with cloud cover but not with such parameter as UV-B. Based on our study, we conclude that areal characteristics of Pohang which represents a typical coastal area may be quite important in explaining the distribution patterns of ozone not only from surface but also from upper atmosphere.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1996.04a
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• pp.144-146
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• 1996

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.239-240
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• 2003

인간활동에 의해 오존이 감소하고 있다는 사실이 1985년 남극지역 전량오존에 관한 보고서로 처음 밝혀진 이후 계속적으로 북극지역과 중위도 지역에서도 동일한 현상이 일어나고 있다고 보고되고 있다(WMO/GAW No.143). 세계기상기구에서는 지상부근의 오존 또는 대기중의 오존전량에 대해서는 1950년대에 처음으로 전지구적차원의 오존관측이 실시되었으며, 1980년대초에 세계기상기구가 발족시킨 전지구오존관측시스템(Global Ozone Observing System, GO$_3$OS)에 의해 전세계적인 관측을 실시하고 있고 있다. (중략)

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.3
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• pp.74-99
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• 2022

Surface ozone is produced by photochemical reactions of nitrogen oxides(NOx) and volatile organic compounds(VOCs) emitted from vehicles and industrial sites, adversely affecting vegetation and the human body. In South Korea, ozone is monitored in real-time at stations(i.e., point measurements), but it is difficult to monitor and analyze its continuous spatial distribution. In this study, surface ozone concentrations were interpolated to have a spatial resolution of 1.5km every hour using the stacking ensemble technique, followed by a 5-fold cross-validation. Base models for the stacking ensemble were cokriging, multi-linear regression(MLR), random forest(RF), and support vector regression(SVR), while MLR was used as the meta model, having all base model results as additional input variables. The results showed that the stacking ensemble model yielded the better performance than the individual base models, resulting in an averaged R of 0.76 and RMSE of 0.0065ppm during the study period of 2020. The surface ozone concentration distribution generated by the stacking ensemble model had a wider range with a spatial pattern similar with terrain and urbanization variables, compared to those by the base models. Not only should the proposed model be capable of producing the hourly spatial distribution of ozone, but it should also be highly applicable for calculating the daily maximum 8-hour ozone concentrations.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.35-42
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• 2022

To investigate the effects of ozonated water concentration and soaking time on adventitious root formation of willow, we studied the efficiency of root cuttings in the revegetation technology of biological engineering of willows. The ozonated water concentrations were used for 5 minutes and 2 hours at 1, 5, 10, 15, 20 ppm by soaking method and then the shoot characteristics were observed. The number and length of adventitious roots were determined. The results indicated that 20 ppm of ozonated water for 2 hours and 1 ppm of ozonated water for 5 minutes resulted in leaves turned wither away and no adventitious root production. Considering the appearance, number and length of the adventitious root, soaking willow cuttings into the ozonated water with dissolved ozone concentration, 5 ppm for 2 hours and 10-15 ppm for 5 minutes were suitable for generating adventitious roots.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.2 no.4
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• pp.26-32
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• 1991

Korea Aerospace Research Institute(KARI) performs research on developing the scientific sounding rocket(KSR-420S) for measuring ozone profile and atmosphere layer over korean peninsula. Informations about performances of flighting scientific rocket, that is temperature, strain, acceleration, pressure, rocket attitude and ranging data, and measuring data of ozone, ionosphere and X-ray are transmitted ground system by rocket onboard transmitting system. In this paper, the telemetry ground system which is compatible with the KSR-420S is designed for tracking the trajectory and receiving the incoming signals.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.8-11
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• 1998

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1995.10a
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• pp.127-128
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• 1995