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.

강우계측망이나 인공위성을 이용하여 어떤 지역의 강우를 관측할 경우 각 관측방법의 특성에 따라 관측오차가 발생하게 된다. 즉, 강우계측망을 이용할 경우 관측된 강우는 시간적으로 연속이지만 공간적으로는 불연속의 특성을 갖게 되고 인공위성을 이용하는 경우 강우는 공간적으로는 연속이지만 시간적으로 불연속인 특성을 나타내게 된다. 이에 따라 관측오차의 계산은 강우의 시간적-공간적 통rP특성과 관측방법에 따라 각각 다르게 정량화된다. 현재 이 문제와 관련하여 No

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.

In order to grasp a characterization of low boiling point chlorinated organic compounds, this study which were carried out at the 8 stations for precipitation samples in the Pusan area during the period from February to September 1995. As a result, low boiling chlorinated organic compounds were estimated that it was dissolved by a portion of precipitation, and it be able to shift at the surface of the each. Concentration of low boiling point chlorinated organic compounds in precipitation are increased with increase of temperature, and estimated that air pollution compounds of as a rule in atmosphere.

The analyzed results of observed precipitation and its pH in Kwangju for 262 days from Jan. 1, 1991 to Dec. 31, 1995 are as follows. The annual mean pH was 5.7, and the monthly mean pH values of January-May and November were less than 5.6 in Kwangju. The ratio of acid rain for these periods was about 48.1 %, almost half that of the total observed days. In March, the pH was 5.4 and the ratio of acid precipitation was 69%, an especially serious situation. In the spring, the pH value was 5.5 thus weak acidic. The pH of precipitation tended to decrease with greater precipitation. The relation between persistent time and pH of precipitation is variable, but if the persistent time is long, the pH is constant and low. It is fortunate that there is an increasing trend of pH in interannual variation, but it is thought important that the amplitude of variation of pH in 1995 was high and the pH value was 4.1 in October and November. Because heavy and persistent precipitation effects the accumulation of acidity, more concern about acid rain is needed.

Observational date is integral in our understanding of present climate, its natural variability and any change due to anthropogenic effects. This study incorporates a brief overview of sampling requirements using data from the first ISLSCP Field Experiment (FIFE) in 1987 which was a multidisciplinary field experiment over a 15 km grid in Konza Prairie, USA. Sampling strategies were designed for precipitation and soil moisture measurements and also detecting land cover type. It was concludes that up to 8 raingages would be needed for valuable precipitation measurements covering the whole FIFE catchment, but only one soil moisture station. Results show that as new gages or station are added to the catchment then the sampling error is reduced, but the improvement in error performance is less as the number of gages or stations increases. Sampling from remotely sensed instruments shows different results. It can be seen that the sampling error at larger resolution sizes are small due to competing error contribution from both commission and omission error.

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.

The aim of the present study is to investigate the interannual variabilities of the East Asia monsoon rainfall associated with the global sea surface temperature anomaly(SSTA). For this study, the summer rainfall(from June to August) over the twenty-eight period of 1961-1988 were analyzed with being divided by nine-subregions over East Asia including Korea, China and Japan. From the analysis of the principal modes explaining the interannual variation, the interannual variabilities of summer rainfalls in South Japan and Korea are larger than those of the other subregions of the East Asia. There is a strong negative correlation between the summer rainfalls of south China and Korea. In this study, the relationship between the summer monsoon of each subregion and SSTs of the tropical NINO regions, of western Pacific warm pool, and of the subtropical ocean were investigated. The longitudinal sections of the lagged cross correlations of the summer rainfall anomaly in (a) Korea and (b) south China, and the monthly SSTA in the equatorial (averaged from 6S to 6N) Pacific were analyzed. The negative maximum correlation pattern of Korea`s summer rainfall and SSTs over the eastern Pacific is transfered to positive maximum correlation over central Pacific region with a biennial periodicity. In South China, the significant positive correlations are found at -12 month lag over the eastern Pacific and maximum negative correlation at +6 month lag over the central Pacific with the quasi-biennial oscillation. But the correlation coefficient reverses completely to that in Korea. In order to investigate the most prevailing interannual variability of rainfall related to the favored SSTA region, the lagged cross correlations between East Asia rainfall and SSTs over the NINO regions(NINO 1+2(0-10S, 90W-80W), NINO 3(5N-5S, 150W-90W), NINO 4(5N-5S, 160E-150W) and the western Pacific warm pool (5N-5S, 120E-160E) were analyzed. Among the lagged cross-correlation cycles in NINO regions, the maximum correlations for the negative lagged months prevail in NINO 1+2 and NINO 3, and the cross correlations for the positive lagged months NINO 4. It is noteworthy that correlation between the western Pacific warm pool SSTA and the monsoon rainfall in Korea and South China have the maximum value at negative 4 month lag. The evolution of the correlation between the East Asia monsoon rainfall and SSTA is linked to the equatorial convective cluster and related to northward propagating situation, and raising the possibility that the East Asia monsoon precipitation may be more fundamentally related to the interaction of intraseasonal oscillations and the sub-regional characteristics including the surface boundary conditions and the behavior of climatological air mass.

An attempt was made to study the subdivision of Korea by the annual amount and the annual change pattern of monthly precipitation days(that is one of the important elements of the precipitation characteristics), using the mean values for the years 1961-1990 at the 68 stations. The amplitudes of annual change were normalized and,using these values,the principal component analysis was applied to determine the annual change patterns.The results show that they are expressed by the combinations of the three change patterns in almost whole regions of Korea.As a result,the annual change pattern of precipitation days in Korea is classified into 8 types from A to e,in detail,36 types from A0 to e②.And regional division of precipitation days in Korea is divided into 13 regions from Ⅰa to ⅢC,into detail,41 regions from I a0 to ⅢHCl.

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.