• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.113-125
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• 2011

In this study, recent trends of the annual precipitation, the annual maximum precipitation of different durations and the rain days over several thresholds(i.e. 0, 10, 20, 40, 60 and 80 mm/day) according to the different local features were analyzed using daily precipitation data of 59 weather stations between 1973 and 2009. To analyze the variability according to the regional characteristics, 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 overall trend of variables increases except rain day. Results according to the regional characteristics showed that the increase trend becomes stronger with elevation increase. The increase trend of Han river basin is largest and that of Youngsan river basin is smallest. Also the increase trend becomes stronger with latitude increase and that of East coast is larger than that of South coast since it may be caused by the regional difference of elevation. The increase trend of urban area is larger than that of rural area. Overall trend showed that increase trend becomes stronger with elevation and latitude increase.

• Journal of Korea Water Resources Association
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• v.48 no.3
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• pp.185-196
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• 2015

A conceptual watershed model HSPF (Hydrological Simulation Program-Fortran) was applied to the Hwangryong river watershed to evaluate climate change effects on pollution loads of the river. For modeling purposes, the Hwangryong river watershed was divided into 7 sub-watersheds. The model was calibrated and validated for the river discharges against the data observed in 2011 at several monitoring stations. The RCP scenarios were set up for the model simulations after being corrected by change factor method. The simulation results of the RCP 4.5 scenario indicate that the annual river discharge and concentrations of BOD, TN, TP of the Hwangryong river will continually increase during the second-half of the 21st century. As for the RCP 8.5 scenario, the simulations results imply that the pollution loads will increase during the middle of the 21st century reflecting the pattern of precipitation. Monthly distributions of the pollution loads for the RCP 4.5 and the RCP 8.5 scenarios show it will increase the most in September and February, respectively.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.338-338
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• 2018

최근들어 지속적인 연강수량의 부족으로 인해 댐 유역의 저류량이 감소하여 해마다 용수부족에 대한 위험성이 높아지고 있다. 댐으로 유입하는 유량은 댐 상류유역의 강우에 의해 발생되는 직접유출과 간접유출에 의해 저류되지만 실제 댐 유량에 크게 기여하는 부분은 유효강우량이상으로 많은 비가 오는 집중호우나 태풍등에 의한 강우로 인해 댐으로 유입되는 유량이다. 그러나 비가오는 기간은 점차 줄어들고 강우의 돌발성은 더욱 증가되고 있어 실제 무강우기간이 길어짐에 따라 토양으로 침투되는 양은 많아지고 댐으로 유입되는 유량의 변화는 과거에 비해 커질 수 있는 현실이다. 본 연구에서는 안동댐 유역의 강우관측소에서 발생한 홍수사상에 대한 유역평균강우를 산정하고 안동댐으로 유입되는 유량을 검토하여 강우와-유출고를 비교검토하여 무강우일수와 유출고와의 관계를 검토하고자 한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.352-356
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• 2012

본 연구는 최근 우리나라 4대강 중 한강의 기후변화로 인한 온도, 상대습도, 강우량의 관측자료를 통해 과거와 최근의 변동특성에 대해서 파악하고자 하였다. 이를 위해 기상청의 관측자료를 활용하였으며 한강의 상, 중, 하류로 나눠서 3개 지점에 대해 선정하였다. 선정 기준은 인위적인 영향을 많이 받는 도시지역을 제외한 도서 지역에 위치한 관측소를 기준으로 선정하였다. 분석을 실시한 항목으로는 최고, 최저, 평균기온 및 상대습도, 연강우량, 일 최고 강우량, 강우 집중률이 있으며 강우 집중률은 강우량에 의한 강우강도의 변동 특성을 파악하기 위해 분석하였다. 과거(~1994)와 최근(1995~2011)의 변동성을 파악하기 위해 각 항목별로 비모수적 검정을 실시하고, 상위 10개를 선정한 자료를 이용하여 분석하였다. 비모수적 검정으로는 Mann-Kendall, Hotelling-Pabst, Sen's Trend Test를 이용하였고, 표준정규변량을 통해 과거와 최근의 경향성을 비교하였다. 연구 지점 중 양평의 평균 기온은 상위 10개 중 9개가 최근 자료에서 선정되었고 경향성의 유의수준도 더 높게 나타났다. 최저 상대습도는 과거에 비해 최근에 더 높은 유의수준의 하강하는 경향성을 가지는 것으로 나타나, 기후변화로 인한 지구온난화가 진행되고 있다는 것을 보여주고 있다. 연강수량은 최근 자료에 상위 8개가 나타났고, 표준정규변량 또한 높은 유의수준을 가지며 증가하는 것으로 나타났다. 일 최고 강수량, 강우집중률 또한 상위 10개 관측자료 중 1995년 이후 7개가 관측되었고, 이는 강우강도가 증가하는 것으로 판단할 수 있다. 상대습도의 경우 평균 및 최소 상대습도에서 2개가 관측 되어 기온은 상승하고 강우는 집중되는 반면 상대습도는 온도의 영향 이외에도 낮아지는 경향을 보여 오난해지는 가운데 건조해지는 경향을 보임을 알 수 있었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.513-521
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• 2008

The objective of this study is the evaluation of the impact on the construction condition due to historical observation data and IPCC SRES A2 climate change scenario. For this purpose, daily precipitation and daily mean temperature data which have been observed over the past 30 years by Korea Meteorological Administration are collected and applied. Also, A2 scenarios during 2011~2040 and 2051~2080 are used for this analysis. According to the results of trend analyses on annual precipitation and annual mean temperature, they are on the increase mostly. The available working day and the day occurred an extreme event are used as correlation indices between climate factor and construction condition. For the past observation data, linear regression and Mann-Kendall test are used to analyze the trend on the correlation index. As a result, both working day and extreme event occurrence day are increased. Likewise, for the future, variation analysis showed the similar result to that of the past and the occurrence frequency of extreme events is increased obviously. Therefore, we can project to increase flood damage potential on the construction site by climate change.

• Journal of Korea Water Resources Association
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• v.35 no.5
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• pp.575-581
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• 2002

This study evaluates the variation of estimation error of area-average rainfall due to rainfall seasonality. Both the cases considering and not considering the spatial correlation are compared to derive the characteristics of estimation error. Similar cases with different accumulation time without considering the rainfall seasonality are also investigated. This study was applied to the Geum-river basin with total 28 rain gauge measurements haying more than 30 years of daily rainfall measurements. As results of the study we found that: (1) The absolute estimation error of monthly area-average rainfall show strong seasonality like the total rainfall amount. However, the relative estimation error normalized by its mean was estimated to have similar values about 5 to 8% except January and December. (2) The relative estimation error of annual area-average rainfall estimated was found to have the estimation error about 3% of its annual mean. (3) However, the relative estimation error normalized by the standard deviation remains almost the same for both monthly and annual rainfall amounts, which was estimated about 11% of its standard deviation. (4) Finally, the estimation error without considering the spatial correlation was found to become almost twice the estimation error with considering the spatial correlation.

• Journal of the Korean earth science society
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• v.27 no.4
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• pp.433-449
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• 2006

Temporal and spatial variations of precipitation in South Korea are investigated using 60 observation data of the recent 30-years from 1976 to 2005. The area averaged annual precipitation amount is about 1310 mm and shows a strong spatial variation, maximum at the southern and Kyoungki province (>1300 mm) and minimum at the Kyungpook province(<1100 mm). The precipitation days show a strong spatial variation with maximum at the Sobaik mountain region(>100 days) and minimum at the Kyungpook province (<90 days). The interannual variations (IAV) of precipitation amount and days are more significant at the southern and eastern part of Sobaik and Taebaik mountain, and along the Sobaik mountain, respectively. So, the difference of annual precipitation amount reaches to about 800mm between wet and dry years at the southern part of Korean peninsula. Whereas, the IAV of precipitation intensity is strong at the southern and middle part of South Korea with a minimum between two maxima. Also, seasonal variations are closely linked with the geographic environments (elevation, distance from ocean, location relative to the Taebaik mountain). Therefore, maximum and minimum of seasonal variations of precipitation are occurred at the northern inland region (ratio of summer to the annual precipitation (RSAP) is greater than 60%), eastern and southern coastal regions (RSAP is less than 53%),respectively. And the RSAP is slightly increased from 50% to 55% comparing the Ho and Kang (1988). The consistent and strong positive relation between the heavy rainfalls, the ratio of heavy rainfalls to annual precipitation and the annual precipitation indicates that heavy rainfall is more frequent and strong at the maximum annual precipitation region.

• Magazine of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.54-64
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• 2011

본 연구에서는 기상청 기상관측소 325개소(기상관서:61개소, 자동기상시스템(AWS):264개소)의 관측자료를 이용하여 우리나라 최근 10년간의 강수 현황, 평년대비 변화 추세, 그리고 전국적 가뭄년도의 강수 특성에 대한 분석을 수행하였다. 최근 10년간의 연강수량은 평년 대비 7.3% 증가하는 추세로서 7월의 경우 평년 대비 25% 증가하나 11월의 경우 34% 감소하여 가뭄과 홍수의 자연재해 발생 위험도가 높아지고 있음을 보여주고 있다. 최근 10년간의 언론보도 조사결과, 가뭄이 발생하지 않은 2003년을 제외하고 매년 지역적 강수부족으로 제한급수가 실시되어져 지역적 강수부족은 매년 존재하고 있음이 확인되었다. 가뭄년도와 비가뭄년도의 월별 강수 변화 분석결과, 최근 20년 전국적 가뭄이 발생한 연도에는 2-5월사이 10년 평균강수량에 못미치는 강수가 발생하고 있음이 나타났고 이 특성을 이용한 누적강수량의 지속적 감시는 가뭄 조기경보 가능성을 보여주고 있다고 사료된다. 이에 관하여 최근 90일 누적 강수량과 댐 수위 상황도를 산출하고 이를 사례분석하여 보았다. 이 방법을 사용할 때 현재(2011년 3월말) 강수부족이 지속된다면 낙동강 중 상류지역에 물부족이 발생 가능성이 높을 것으로 예상된다.

• Journal of Korea Water Resources Association
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• v.38 no.10 s.159
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• pp.885-894
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• 2005

Since the 1970s, rapid Industrialization has brought urbanization nationwide. In this paper, thirty one years data(1973-2003) ate used to evaluate variability of major cities. Before assessing the context between urbanization and variability of rainfall, the rural areas are selected to compare with urban ones. Thus, average, trends, variations, and nonparametric frequency analysis methods were employed for evaluating variation of annual precipitation, seasonal precipitation, 1 hour annual maximum design rainfall and 24 hour annual maximum design rainfall for both urban and rural areas. The result have shown that summer precipitation relatively increased In urban areas compared to that in rural areas.

• Journal of Climate Change Research
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• v.2 no.2
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• pp.133-141
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• 2011

This study is to identify the trend of climate change in Gangwon-do by examining accumulated climate data such as temperature and precipitation in Gangneung city over the past about 100 years. The annual mean temperature and precipitation in Gangneung have increased by $1.4^{\circ}C$ and 14.7%, respectively, over the last 98 years (1912~2009). The trends of Gangneung showed that precipitation has intensified as the number of precipitation days decreased while its amount increased during the period. Based on the temperature data, spring and summer began earlier whereas the onsets of fall and winter were delayed. Summer has become longer and winter shorter by about a month. Averaging observation data from seven weather stations in Gangwon-do, the annual mean temperature and precipitation have increased by $0.8^{\circ}C$ and 21.0% respectively over the last 37 years (1973~2009). By region, Wonju city recorded the biggest increase of $1.6^{\circ}C$ in the annual mean temperature while Sokcho city the smallest increase of $0.4^{\circ}C$. In the annual mean precipitation, Daegwallweong recorded the biggest change of 22.2% and Wonju city the smallest of 12.0%.