• 한국농공학회논문집
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• 제53권3호
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• pp.1-11
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• 2011

The temporal variability of spring (March, April, May) monthly precipitation, precipitation effectiveness, monthly maximum precipitation, monthly precipitation of different durations, and the precipitation days over several threshold (i.e. 0, 10, 20, 30, 40, and 50 mm/day) of 59 weather stations between 1973 and 2009 were analyzed. Also to analyze the regional characteristics of temporal variability, 59 weather stations were classified by elevations, latitudes, longitudes, river basins, inland or shore (east sea, south sea, west sea) area and the level of urbanization. Results demonstrated that trends of variables increase in April and decrease in May except precipitation day. Overall trend of precipitation amount and precipitation effectiveness is same but precipitation effectiveness of several sites decrease despite the trend of precipitation amount increases which may be caused by the air temperature increase. Therefore more effective water supply strategy is essential for Spring season. Regional characteristics of Spring precipitation variability can be summarized that increase trend during May become stronger with the increase of latitude and elevation which is similar to that of Summer season. The temporal variability of variables showed different behaviors according to river basins, inland or shore (east sea, south sea, west sea) area and the level of urbanization.

• 대기
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• 제22권4호
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• pp.449-454
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• 2012

This study presents the long-term variability of spring precipitation over the Korean peninsula. It is found that the significant interdecadal change in the spring precipitation has occurred around year 1991. Over the Korean peninsula the precipitation for the post-1991 period increased by about 30 mm per year in CMAP and station-measured data compared to the precipitation prior to year 1991. Due to an increased baroclinicity during the later period, the low-level negative pressure anomaly has developed with its center over northern Japan. Korea is situated at the western end of the negative pressure anomaly, receiving moisture from westerly winds and producing more precipitation. Also, we estimate the change in the near future (years 2020~2040) spring precipitation using six best performing Coupled Model Intercomparison Project 3 (CMIP3) models. These best model ensemble mean shows that spring precipitation is anticipated to increase by about 4% due to the strengthened westerlies accompanied by the northwestern enhancement of the North Pacific subtropical high.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.1247-1250
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• 2004

The amount of precipitation during El Nino over Korea increases in Summer and Winter. However, it decreases in Fall, and exhibits not much change in Spring. Especially, the amount of precipitation during September of El Nino year is much less than that of the September of non-El Nino year. The amount of precipitation during El Nino year of October and November shows similar amount of precipitation during non-El Nino year of the same period. The reason for decreasing precipitation in September is related to the weakening of the 2nd rainy season during the development of El Nino over East Asia including Korea. Insufficiency of fall precipitation during El Nino year influences drought in Spring for next year.

• 한국대기환경학회지
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• 제15권4호
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• pp.393-402
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• 1999

Precipitation samples were collected by the wet-only sampling method in Iksan in the northwest of Chonbuk from March 1995 to February 1997. These samples were analyzed for the concentration of ion components, in addition to pH and electrical conductivity. The annual mean pH of precipitation was 4.8 and the seasonal trend of pH was shown to be low in Fall and Winter(4.5), middle-ranged in Spring(4.7) and high in Summer(5.0). The frequency of pH below 5.6 was about 71%. The seasonal pattern of pH frequency was found to be different in each season. In the case of the pH less than 5.0, the frequency was higher in Spring, Fall and Winter than in Summer, especially higher in Fall than in other seasons. The concentrations of analysed ions showed a pronounced seasonal pattern. However, major ion species for all seasons were $NH^+_4,;Ca^{2+};and;Na^+$ among cations and $SO^{2-}_4,;Cl^-;and;NO^-_3$ among anions. The major acidifying species appeared to be $nss-SO^{2-}_4;and;NO^-_3$, and the main bases responsible for the neutralization of precipitation acidity were $nss-Ca^{2+};and;NH^+_4$. The potential acidity of precipitation, pAi, was found to be between 3.0 and 5.0 for total samples, while the measured pH was approximately between 3.9 and 7.8. The seasonal trend of pAi showed a decreasing order: Summer (4.3), Winter(4.0), Spring and Fall(3.8). During the Fall, both pAi and pH were especially very low, which indicated that during this period the potential acidity of precipitation was high but the neutralizing capacity was low. For Spring, pAi was very low but pH was slightly high. This was likely due to the large amount of $CaCO_3$ in the soil particles transported over a long range from the Chinese continent that were incorporated into the precipitation, and then neutralized the acidifying species with its high concentraton.

• Korean Journal of Hydrosciences
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• 제7권
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• pp.87-106
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• 1996

A precipitation change scenario in Korea due to atmospheric $ doubling has been provided with a mixed method (Rebinson and Finkelstein, 1991) based on the simulated precipitation data by three GCM(CCC, UI, and GFDL GCM) experiments. Through the analysis the precipitation change by atmospheric $ doubing can be summarized as follows : Korea may have more precipitation as much as 25mm/yr during spring season and more less 50 mm/yr during summer and autumn, respectively. In the contrary Korea may have less rainfall as much as 13 mm/yr during winter. In terms of percentage with respect to current climatological value of precipitation Korea may have more rain as much as 10%, 13% and 24%, respectively, for spring, summer and autumn than current climate. However, Korea may have less precipitation during winter than current climatological average.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권6호
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• pp.37-45
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• 2018

The source of Chusan Spring water in the Ulleungdo is the precipitation in the Nari caldera basin, which permeates in the Trachitic pumice and tuff area and moves downward, outflowing at the lithologic boundary between the trachyte and Nari tuff. It is known that the discharge rate of the Chusan Spring is large enough to be used for the small hydroelectric power generation, but the exact discharge rate and hydrogeologic characteristics have not been known. The discharge rates of the Spring were measured 11 times, which ranged from $15,220m^3/d$ to $36,278m^3/d$. The discharge rates, measured by the automatic level recorder, for two-year period, were $20,000{\sim}38,000m^3/d$. The variation of discharge rates did not coincide with rainfall event, but showed daily increases of $3,000{\sim}5,000m^3/d$. The annual discharge rate excluding the evapotranspiration and the surrounding stream discharge corresponded to 70.6% of the annual precipitation of the recharge area. Therefore, meteorological observations at the Nari basin, rather than the Ulleung-do meteorological station, are more appropriate to properly interpret the discharge characteristics of the Chusam Spring and the recharge rate of the basin.

• 대기
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• 제19권2호
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• pp.155-168
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• 2009

Characteristics of seasonal mean diurnal temperature range (DTR) and their causes over South Korea are investigated using the 60 stations data of Korea Meteorological Administration from 1976 to 2005. In general, the seasonal mean DTR is greatest during spring (in inland area) and least during summer (urban and coastal area). The spatial and seasonal variations of DTR are closely linked with the land surface conditions (especially vegetation activity and soil moisture) and atmospheric conditions (cloud amount, precipitation, local circulation). The seasonal mean DTR shows a decreasing trend at the major urban areas and at the north-eastern part of South Korea. Whereas, it shows an increasing trend at the central area of the southern part. Decreasing and increasing trends of DTR are more significant during summer and fall, and during spring and winter. The decrease (increase) of DTR is mainly caused by the stronger increase of daily minimum (maximum) temperature than daily maximum (minimum) temperature. The negative effects of precipitation and cloud amount on the DTR are greater during spring and at the inland area than during winter and at the coastal area. And the effect of daytime precipitation on the DTR is greater than that of nighttime precipitation.

• 한국환경과학회지
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• 제23권2호
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• pp.193-205
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• 2014

The direct-runoff of South Korea's representative dams (Soyanggang, Chungju, Andong, Daecheong, and Seomjingang) and precipitation were analyzed mainly with the evenly distributed spring rainfall events across the country for the last five years. For precipitation, an increasing was presented during the period 2008-2011, but did not continue to increasing 2012. The average precipitation of the five dams displayed a similar trend. Except for Chungju and Andong Dams, the trend of runoff was similar to the one shown in the precipitation. Despite the precipitation of 2009 increased, the runoff volume decreased for Andong and Chungju Dams. In addition, Chungju Dam remarkably showed a bigger runoff volume compared to other dams. As for the Sumjingang Dam, the runoff volume was the smallest, and the difference is as great as over 15-fold when compared to other runoff values. After the result of analyzing the relation between a single runoff event and synoptic weather patterns, pattern 4 contributed to the greatest impact on this event and weather patterns. The total runoff volume of the five dams for spring rain event for the last five years that exhibited this characteristic was estimated at 5.68 billion tons($10^6m^3$). Lastly, the value of this estimation was assessed as approximately 273.1 billion KRW.

• 물과 미래
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• 제28권3호
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• pp.143-157
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• 1995

대기중 $CO_2$ 배증에 따른 한반도 강수량 변화가 3개 GCM(CCC, UI와 GFDL)의 기후변화 실험에 따른 광역적 강수변동 자료로부터 Robinson과 Finkelstein이 제시한 혼합적 방법에 의하여 계산되었다. 계산 결과 도출된 대기중 CO$ 배증에 따라 예상되는 강수량 변화는 다음과 같다. 봄철에 예상되는 강수량 증가는 약 25mm/yr정도이며 여름철과 가을철의 강수량 증가는 50mm/yr를 상회하였다. 그러나 겨울철에는 13mm/yr 감소하였다. 현 강수량에 대한 백분율로 보면 봄철, 여름철과 가을철에 각각 10%, 13%와 24%의 강수량 증가를 보인 반면에 겨울철에는 현재보다 다소 감소할 것이 예상된다.

• 한국지구과학회지
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• 제21권1호
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• pp.81-92
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• 2000

본 연구는 한라산 지역에 분포하는 대표적인 9개 용천수에 대한 고도별 수질특성과 그 진화과정을 연구하였다. 조사 지역 9개 용천수의 수질분석결과 관음사용천수는 수소이온 농도에서 비정상적인 수질특성을 보였다. 해발고도 1000m 이하에 위치하는 영실, 남국선원, 성판악, 어리목 및 관음사용천수에서는 염소이온, 황산이온, 질산성질소 및 나트륨이온 함량이 높아 주변 육상오염원들에 의해 오염이 진행 중인 용천수로 분류된다. 중탄산이온, 황산이온 및 수소이온 농도는 강수량이 많았을 때 그 농도가 증가하였으며, 염소이온, 칼슘이온 및 질산성질소 농도는 강수량이 많았을 때 그 농도가 감소하였고, 마그네슘이온, 나트륨이온 및 전기비전도도 농도는 강수량의 영향이 미미하였다. 한라산 용천수는 백록담 담수와 윗세오름용천수를 제외한 전 용천수가 나트륨 또는 칼륨형(sodium or potassium type)과 중탄산형(bicarbonate type)의 용천수군으로 구분된다.