This study was conducted to investigate the characteristics of surface ozone concentration and occurrence of high ozone concentration using hourly ozone, nitrogen dioxide and meteorological data for 1997∼1998 in Pusan coastal area. Monthly mean ozone concentration was the highest at Dongsamdong in Spring(35.4ppb), at Kwangbokdong in Fall(25.lppb) and the lowest Dongsamdong(22.2ppb) and Kwangbokdong(16.0ppb) in Winter. Relative standard deviation indicating clearness of observation site was 0.42 at Dongsamdong and 0.49 at Kwangbokdong that is similar to urban area. The diurnal variation of ozone concentration of Dongsamdong and Kwangbokdong showed maximum at 1500∼1600LST and minimum 0700∼0800LST that typical pattern of ozone concentration. In ozone episode period(Sept. 10∼15, 1998), diurnal change of ozone concentration was very high, and ozone concentration was related to meteorological parameters such as temperature, relative humidity, wind speed, cloud amount and radiation on a horizontal surface. During the episode days peak ozone concentrations are much higher than the normal values, wind speeds are always lower, and solar radiation is high with the exception of the September episode.

This study was performed to investigate the characteristics of nocturnal maximum ozone occurrence and the meteorological relevance using to hourly ozone data and meteorological data for 1995∼1996 in Pusan coastal area. Kwangbokdong showed the highest occurrence of nocturnal maximum ozone as 36.9%, and Deokcheondong showed the lowest occurrence(9.2%) for research period in Pusan. The occurrence rates of nocturnal maximum ozone concentration were decreased toward land area. The low maximum temperature, high minimum temperature, low diurnal range, high relative humidity, high wind speed, high cloud amount, low sunshine and low radiation were closely related to the main meteorological characteristics occurring the nocturnal maximum concentration of ozone. It was shown that normal daily variation of ozone concentration by strong photochemical reaction at the before day of nocturnal maximum ozone. The concentration of nocturnal maximum ozone were occured by entrainment of ozone from the upper layer of developed mixing layer. There are no ozone sources near the ground at night, so that the nighttime ozone should be entrained from the upper layer by forced convection.

This study was conducted to examine the monthly and seasonal variation of SO2, TSP, O3 concentration in Dongsamdong, Pusan coastal area. And the characteristics of air pollution of this area was compared to Kwangbokdong in Pusan and Taehadong in Ullungdo. Monthly mean concentration of SO2 and TSP showed lower than Kwangbokdong, O3 was higher than Kwangbokdong. In case of SO2, seasonal variation of Dongsamdong was remarkabler than Kwangbokdong and the concentration difference of early morning and daytime was higher than Kwangbokdong, Taehadong showed very lower concentration as background area. In case of TSP, Dongsamdong was lower concentration and smaller diurnal change than Kwangbokdong, Taehadong showed very lower concentration as background area. In case of O3, Dongsamdong was l0ppb higher than Kwangbokdong at daytime maximum concentration, diurnal change of concentration was higher, too. In case of frequency distribution of concentration, SO2 and TSP at Dongsamdong showed higher frequency in low concentration class and O3 showed in high concentration class as compared with Kwangbokdong.

The low level atmospheric observation carried out to investigate magnitude, formation and dissipation of nocturnal surface inversion layer, also to survey relation to each meterological parameter in inversion layer at Pusan power plant for Oct. 13, 1996. As coastal area, the surface inversion layer height was relatively high(186m), and after sunset unstable layer formated from surface to around 40m, and the inversion layer was left still in the upper layer. The surface inversion layer dissipated at 0920LST perfectly. The layer that strong inversion layer was formated, showed steep variation of potential temperature and wind speed and relative humidity.

The purpose of this study is investigated to suggest the governmental policy and guideline required to establish the coastal zone management and development plan in the Pusan metropolitan city. The results are found as follows : first, a new definition of 'coastal zone'is introduced based on the geophysical characteristics in the city. Second, new policy-oriented guidelines are built on the basis of the coastal function from the viewpoint of the coastal zone management. Third, the coastal zone of the city is classified into 3 sub-zone by the geophysical characteristics. Fourth, the comprehensive coastal zone management and development plan is suggested.

We have analyzed focusing on the characteristics, speed and width of sea breeze front in Pusan coastal area using the meteorological data observed at Kimhae air force meteorological station because the presence of the front has important effects on the distribution of air pollution. The inland penetration of sea breeze front was recognized by steep variation of meteorological parameters(wind direction, wind speed, temperature, dew point temperature, air pressure, relative humidity) before and after its passage and the variation of SO_2 concentration, the speed and width of the sea breeze front was 2.07m/s and 217m, respectively. The structure and inland penetration of sea breeeze front should be taken into account whenever a model is to be compared with detailed field measurements.

Numerical simulations of photochemical air pollution (CBM: Carbon-Bond Mechanism) under a theoretical three-dimensional local wind system are carried to clarify the fundamental characteristics of the effects of local wind on photochemical air pollution. According to the AWS data of Pusan coastal area and KMA, the surface wind of Pusan during summertime showed a very remarkable land and sea breeze circulation. The ozone concentration distribution using local wind model showed that high ozone concentration zone near coastal area moved toward inland in the afternoon. This change implies a sea breeze increases the ozone concentration, but a land breeze decreases it in Pusan coastal area

Pusan is the largest coastal city with a population of about four million in Korea. Because of increased and confused traffic, photochemical air pollution become a major urban environmental problem recently. The photo-chemical air pollution weather forecasting method preciser than existing air pollution forecast method has been developed to forecast ozone episode days with meteorological conditions using the data measured at 7 air quality continuous monitoring stations from June to September using 2 years (1994, 1995). The method developed in present study showed higher percentage correct and skill score than existing air pollution forecasting in KMA (Korea Meteorological Administration).

Air pollution characteristics and the influence of sea breeze on surface ozone concentration were studied using the data measured at 7 air quality continuous monitoring stations from June to September using 3 years (1990, 1993, 1994) in Pusan coastal area. Among the 246 sea breeze days for research period, there were approximately 89 sea breeze days (36%) from June to September. And there were 120 the episode days (68%) of ozone greater than or equal to 60 ppb in summer season. In 89 sea breeze days, the episode day was highly marked as 56 days (63%). So, we knew that the sea breeze greatly affects the occurence of ozone episode day. the ozone concentration under the condition of the sea breeze increase about 40% in the daytime. Frequencies distribution of O3 concentration for sea breeze moved toward high concentration class. The characteristics of ozone concentration in relation to meteorological conditions of sea breeze is significant because we can discover major weather factors for eastablishing an air pollutionweather forecast system. For further study about meterological approach method for photochemical air pollution, it is necessary to explain the characteristics of atmosphere below 1,000 m, especially concerning the formation mechanism of inversion layers. And finally, we will study the relationships to synoptic weather conditions and vertical structure and diurnal variation of local wind systems including sea breeze, and the vertical movements of atmosphere in the city.

We have studied the characteristics of wind over Pusan coastal area in order to precisely predict surface wind having an important effect on oil spill fate using the data on surface observation of Pusan, Kimhae and Gadeogdo island which are collected during the 3 years from 1988 to 1990. We also investigated the correlation of the surface wind between Pusan, Kimhae and Gadeogdo island. In both Pusan areas and Kimhae, the land and sea breeze occurs during the whole season except for winter. The occurrence frequency of land and sea breeze is significantly high from April to August. The correlation of surface wind between Pusan, Kimhae and Gadeogdo island surface wind is high in the daytime. The occurrence frequency of sea breeze in the Kimhae areas is higher than that in pusan on the basis of the present criteria. For monthly occurrence, Pusan has the highest occurrence frequency of the sea breeze in August and Kimhae has in May.

The land and sea breeze over the Pusan coastal area is studied by three dimensional mesoscale numerical model. According to the results of the simulation experiments, both Pusan areas and Kimhae areas, the sea breeze began at 0800LST and the strongest at 1500LST and then at 1800LST. After midnight, the sea breeze changed about the land breeze and become weaker than that of the sea breeze in the daytime. Comparisons between calculations and observations showed that the characteristics of diurnal variation and v-component of the wind velocity relatively is similar to the Pusan areas. On the Kimhae areas, however, observations showed time lag which compared to the results of simulation experiments in the velocity of sea breeze and diurnal variation. From the above results, comparisons between calculations and observations is much more similar to the coastal areas than on the inland area.