A preliminary study on the chemical compositions of forty seven precipitations from March 1994 to May 1995 in Yeoncheon-gun, which is adjacent to the southern boundary of demilitarized zone (DMZ) in the northernmost tip of Kyunggi province has been performed. The metal cation and anion concentrations were measured by atomic absorption spectrometer and ion chromatography, respectively. pH/Ion meter and direct nesslerization method were used for the concentration measurements of H- ion and NH_4+ ions, respectively. Based on the data, the quantitative orders of the cation and anion average concentrations were Ca2+ > NH_4+ > Na+ > K+ > Mg2+ > H+ and SO_42- > Cl- > NO_3-, respectively. The ratio of average total anion concentration to average total cation concentration was 0.97. The average pH value of the precipitations was 5.60. These results, correlation coefficients between the ion concentrations, and monthly variations of pH value and precipitation amount are used for chemical analysis on the environmental pollution and pollutant sources in Yeoncheon-gun of Kyunggi province near DMZ.

This paper aims to estimate the change point of the precipitation in Pusan area using the several statistical approaches. The data concerning rainfall are extracted from the annual climatological report and monthly weather report issued by the Korean Meteorological Administration. The average annual precipitation at Pusan is 1471.6 ㎜, with a standard deviation of 406.0 ㎜, less than the normal(1486.0 ㎜). The trend of the annual precipitation is continuously decreasing after 1991 as a change point. And the statistical tests such as t-test and Wilcoxon rank sum test reveals that the average annual precipitation of after 1991 is less than that of before 1991 at 10% significance level. And the mean annual precipitation in Kyongnam districts is also continuously decreasing after 1991 same as Pusan.

This study was carried out to investigate the characteristics of chemical components and precipitation at Kimhae area from March, 1992 to June, 1994. The pH values, concentration of soluble ions(Cl^-, NO_2^-, NO_3^-, SO_4^2-, PO_4^3-, F^-, Mg^2+, Ca^2+, Mn^2+, K^+) and nonsoluble metals(Cr, Si, Zn, Pb, Cu, Fe, Mn, Mg, Al, V, Ca) were measured by pH meter, IC(Ion Chromatography) and ICP(Inductively Coupled Plasma). The data were analyzed by the daily, hourly distribution characteristics of acidity and chemical components, as well as the correlation between them. The results are as follows. 1. The pH range of precipitation was from 3.45 to 6.80 in Kimhae area, and average value was pH 4.62 and main chemical components were SO_4^2-, Cl^-, NO_3^-. The highest pH value and concentration appeared in initial rain, which might result from urbanization and industrialization in this area and long term transportation from China. 2. The hourly correction distribution of main anions related to pH value in the rainwater showed SO_4^2- > NO_3^- > Cl^-. Hourly concentration of heavy metal and each ion was highly correlated with pH in the precipitation.

1961년 이전에 관측이 시작되어 30년 이상의 관측자료가 있는 기상청의 15개 관측소의 강수량 자료를 이용하여 우리나라의 여름철 강수량 분포 특성을 조사하였다. 특히 이 연구에서는 우리나라 강수량 기후 평년값을 이용하여 기후적 특성을 조사하였으며, 지역별로 연 강수량, 여름철 강수량, 장마기간중 강수량의 연도별 변동을 비교 분석하고 그 상관을 조사하였다. 대체로 우리나라의 경우 연 강수량의 반 이상이 6, 7, 8월의 여름철에 집중되어 있고, 또 이

The characteristics on the transtion probabilities and periodicity for the daily precipitation occurrence in Korean peninsula are investigated by applying the Markov chain properties to daily precipitation occurrence. In order to examine the responses of Markov Chain properties to the applied period and their magnitudes, three cases (Case A: 1956∼1985 at 14 stations, Case B: 1965∼1994 at 14 stations, and Case C: 1985∼1994 at 63 stations) are considered in this study. The transition probabilities from wet day to wet day for all cases are about 0.50 and in summer, especially July, are higher. In addition, considering them in each station we can find that they are the highest at Ullung-do and lowest at Inchon for all cases. The annual equilibrium probabilities of a wet day appear 0.31 in Case A, 0.30 Case B, and 0.29 Case C, respectively. This may explain that as the data-period used becomes shorter, the higher the equilibrium probability is. The seasonal distributions of equilibrium probabilities are appeared the lowest(0.23∼0.28) in winter and the highest(more than 0.39) in spring and monthly in July and in October, repectively. The annual mean wet duration for all cases is 2.04 days in Case A, 1.99 Case B, and 1.89 Case C, repectively. The weather cycle obtained from the annual mean wet and dry duration is 6.54∼6.59 days, which are closely associated with the movement of synoptic systems. And the statistical tests show that the transitions of daily precipitation occurrence for all cases may have two-state first Markov chain property, being the stationarity in time and heterogeneity in space.

This study is an attempt to investigate the chemical components of precipitation and its variation according to surface wind. Precipitation samples were collected by an wet-only precipitation sampler during the period of October 1994 to September 1995 at Kyungsan in Korea. The results obtained in this study are summerized as follows. The annual average of precipitation pH is 5.0, the highest month of pH is July of 5.5, and the lowest month of pH is December of 4.4. The most frequent appearance is in the range of pH 5.0 to 5.5 and its rate is 56.8%. The order of ion concentration in precipitation is SO4^2->NO3^->Cl^-in case of anion and Ca^2+>NH4^+ >Na^+>Mg^2+ in case of cation. It is found from our analysis that the correlation coefficient among the precipitation pH and ion components is below r=0.3, while the correlation coefficient between SO4^2- and NO3, Na^+ and Cl^- is above r=0.8, respectively. The mean pH of precipitation is 4.8 under the westerly wind and 5.2 under the easterly wind. The concentrations of anion and cation under the westerly wind are more than the concentrations under the easterly wind. In autumn, the concentration of Na^+ and Cl^- under the easterly wind are higher than the concentration under the westerly wind. The correlation coefficients between wind speed and pH, ion components show very low correlation of -0.41≤r≤0.2. But the present study show that the correlation coefficient between wind speed and pH of precipitation is positive and the correlation coefficients between wind speed and ion concentration is negative.

A comparative study on the chemical compositions of precipitations from February 1993 to April 1993 in Sungnam city of Kyunggi province, Inchon city, Kangneung city of Kangwon province, and Chongwon-gun of Chungbuk province has been performed. The metal cation and anion concentrations were measured by atomic absorption spectrometer and ion liquid chromatography, respectively. pH/Ion meter and direct nesslerization method were used for the concentration measurements of H^+ and NH_4^+ ions, respectively. The quantitative orders of the cation and anion average concentrations, correlation coefficients between the ion concentrations, and pH values are used for chemical analysis on the environmental pollution and pollutant sources in the urban, surburban, seaside, and rural areas of the Korean Peninsula.

It is very important to assess accurately the terms which are included in the heat budget equation of soil surface because they are used in the GCM and meso-scale circulation modeling as well as in the micrometeorological studies. Each terms in the heat budget equation change according to the soil moisture content. So, it is necessary to specify clearly the relations between soil moisture content and these terms. Special experiment with ricrometeorological measurements was executed to study these relations at Environmental Research Center of Tsukuba University, Japan. The results are as follow: 1. The soil moisture contents of 1 ㎝ and 4 ㎝ depth are oscillated with one day period in drying process and the amplitude of variation of l cm depth is greater than that of 4 ㎝. 2. Increase in soil moisture contents due to precipitation result in decrease of albedo with step function. 3. Sensible heat is in reverse proportion to the soil moisture content and latent heat is in direct proportion to it. Latent heat is more sensitive than sensible heat according to the soil moisture variation. Net long wave radiation have high correlation with soil moisture. 4. Comparing with the radiative term with the flux term in wetting process due to precipitation, the energy transfer of the aero and thermodynamic flux is greater than that of the radiative heat flux.

The amount of inorganic ions such as Na^+, K^+, Ca^2+, Mg^2+, NH_4^+, Cl^-, NO_3^-, and SO_4^2- in the precipitation at Chongwon area were analyzed during the period of February 1991 - June 1993. Ammonium ion was analyzed using Nessler and indophenol methods. Cations were determined by atomic absorption spectroscopy, and ion chromatography was used for anions. For the entire period of study, there was no particular ion which has significantly high correlation coefficient with hydrogen ion. The correlation between NO_3^-, and SO_4^2- was 0.6, which suggests that these ions may be from the same source. Most cations have high correlation with each other. In the seasonal analysis, the nitrate and sulfate ions have high correlations with the acidity in the fall and winter. The rain waters of Taeahn area showed usually high concentrations of the ions, even though the pH was much higher than that of Chongwon area. It is considered that the ions came as neutral salt in Taeahn, while NO_x and SO_x contributes largely to the acidity of rains in Chongwon.

This paper aims to know the characteristics of occurrence of the anomaly level and variability of the monthly precipitation in Kyeongnam, Korea. For this study, it was investigated the distribution of the annual and monthly mean precipitation, the precipitation variability and its annual change, and the characteristics of occurrence of the anomaly level in Kyeongnam area. The results were summarized as follows ; 1) The mean of annual total precipitation averaged over Kyeongnam area is 1433.3mm. The spatial distribution n of the annual total precipitation shows that in Kyeongnam area, the high rainfall area locates in the southwest area and south coast and the low rainfall area in an inland area 2) Monthly mean precipitation in Kyeongnam area was the highest in July(266.4㎜) followed by August(338.0㎜), June(210.2㎜) in descending order. In summer season, rainfall was concentrated and accounted for 49.9 percent of the annual total precipitation. Because convergence of the warm and humid southwest current which was influenced by Changma and typhoon took place well in this area. 3) The patterns of annual change of precipitaion variability can be divided into two types; One is a coast type and the other an inland type. The variability of precipitation generally appears low in spring and summer season and high in autumn and winter season. This is in accord with the large and small of precipitation. 4) The high frequency of anomaly level was N( Normal)-level and the next was LN( Low Normal)-level and ES(Extremely Subnormal)-level was not appeared in all stations. The occurrence frequency of N level was high in high rainfall area and distinguished in spring and summer season but the low rainfall area was not.

A study on acidity in precipitation was carried out during May 1990 - April 1991 at two sites in Chongwon, Choongbook. We observed variations of pH from 4.0 to 7.0. Annual mean value of pH was 5.21 in the area. In particular, strong acidity of rain fall, pH 4.0 were observed during winter to early spring. Neutral values were observed during June to July and were due to wet deposition of atmospheric pollutants by stationary fronts in the rainy season. Interestingly, acidity of snow observed in winter was neutral and it was weaker than the acidity of rain in winter by a value of 2.0. Discussion is made on meteorological and chemical analyses and seasonal variations of acidity of precipitation.