• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.517-520
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• 2003

The snow-fatting measurement system including the snow sensor applying the photo-coupler is investigated in this study and using this snow sensor the height of snow fallen is measured. To measure the snow depth, five photo sensors are arranged with 5 mm distance. The snow-falling measurement system, which is measuring the motor revolution controlled with stepping motor, is mounted above the snow surface. From this work, it is feasible to measure quantitatively the snow on real time. Its software implements a proven method to achieve valid measurements also under difficult conditions as future study. In cases where the snow sensor is applieded to the prediction of snow in the meteorological observation system and the snow removing system, it is recommend the GRS-Option in order to improve the quality of snow measurements for better compensation.

• Wind and Structures
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• 제37권1호
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• pp.25-38
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• 2023

Due to the complexity and difficulty in meeting the multiphase flow complexity, similarity, and multiscale characteristics, the mechanism of snow drift is so complicated that the snow deposition prediction is still inaccurate and needs to be far improved. Meanwhile, the validation of prediction methods is also limited due to a lack of field-measured data about snow deposition. To this end, a field measurement activity about snow deposition around a cube with time was carried out, and the snow accumulation process was measured under blowing snow conditions in northwest China. The maximum snow depth, snow profile, and variation in snow depth around the cube were discussed and analyzed. The measured results indicated three stages of snow accumulation around the cube. First, snow is deposited in windward, lateral and leeward regions, and then the snow depth in windward and lateral regions increases. Secondly, when the snow in the windward region reaches its maximum, the downwash flow erodes the snow against the front wall. Meanwhile, snow range and depth in lateral regions have a significant increase. Thirdly, a narrow road in the leeward region is formed with the increase in snow range and depth, which results in higher wind speed and reforming snow deposition there. The field measurement study in this paper not only furthers understanding of the snow accumulation process instead of final deposition under complex conditions but also provides an important benchmark for validating prediction methods.

• 한국농림기상학회지
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• 제4권4호
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• pp.248-253
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• 2002

본 논문은 우리나라 기원전 6년 11월부터 1928년 까지 1934년 간의 강설기록을 살펴 본 것으로서 다음과 같은 특징을 정리할 수 있었다. 첫눈 기록은 733년 7월에 신라땅과 1637년 전라도 무주에서 있었고 끝눈 기록은 6월 11일에 눈보라가 온 것으로 기록되어 한 여름에도 눈이 왔었다는 사실을 확인할 수 있다. 적설량은 척관법 단위를 써서 기록하였는데 최고 적설량은 약 열 자 혹은 한 장(장여 혹은 일장) 기록이 있었으며 자주 나타나는 큰눈 기록은 대개 4∼5자가 많이 발견된다. 단위를 치(촌)와 푼(분)까지 사용하여 기록한 바 정확성을 기하려 한 흔적도 보인다. 눈피해는 주로 인명과 가옥 등을 중심으로 기록하고 있다. 눈피해 중 인명피해로는 크게 3건이 발견된다. 1524년과 1521년에 함경도 경성 땅에서 각각 100여명과 140여명, 1670년에는 제주도에 큰눈이 내려 91명이 사망한 것으로 기록되어 있다. 첫눈이 오면 상서로운 것으로 여겨 나라에서는 신설하례(新雪賀禮) 의식을 갖고 나라의 안녕을 기원하였고, 눈이 오지 않으면 왕에게 간하여 기설제를 지내기도 하였다. 눈과 관련된 기상이변은 여러 번 발견된다. 눈 올 때 심한 천둥번개가 친다거나, 이상한 벌레들이 섞여 내린다거나 붉은 색깔의 눈이 내렸다는 기록이 있다. 검색한 결과는 단어별 건수에 있어서나 내용에 있어서나 미진한 것이다. 검색방법이나 검색에 사용해야 할 단어 중에는 좀 더 합당한 단어들이 있을 줄 안다. 차후의 연구를 위한 과제로 남기기를 희망한다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.992-996
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• 2008

In this study, changes in precipitation across South Korea during snow seasons (November-April) and their potential are examined. Current (1973/74-2006/07) and future (2081-2100) time series of snow indices including snow season, snow-to-precipitation ratio, and snow impossible day are extracted from observed snow and precipitation data for 61 weather stations as well as observed and modeled daily temperature data. Analyses of linear trends reveal that snow seasons have shortened by 3-13 days/decade; that the snow-to-precipitation ratio (the percentage of snow days relative to precipitation days) has decreased by 4-8 %/decade. These changes are associated with pronounced formations of a positive pressure anomaly core over East Asia during the positive Arctic Oscillation winter years since the late 1980s. A snow-temperature statistical model demonstrates that the warming due to the positive core winter intensifies changes from snow to rain at the rate of $4.7cm/^{\circ}C$. The high pressure anomaly pattern has also contributed to decreases of air-sea thermal gradient which are associated with the reduction of snow could formation. Modeled data predict that a fingerprint of wintertime global warming causing changes from snow to rain will continue to be observed over the 21st century.

• Ocean and Polar Research
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• 제37권2호
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• pp.141-147
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• 2015

Snow albedo can be decreased if there are any impurities on the snow surface other than the snow itself. Due to the decrease of snow albedo, melting rates of surface snow can increase, which is very crucial in climate change and hydrogeology in many parts of the world. Anthropogenic black carbons caused by the incomplete combustion of fossil fuel affect snow and tephra particles generated by geologic volcanic activities reduce snow albedo. In this study, we investigated isotopic compositions for snow covered by tephra particles and compared with this with clean snow. Isotopic compositions of snow with tephra statistically show more enriched than those of clean snow (p<0.02). This can be explained by the fact that snow becomes enriched in $^{18}O$ or D relative to meltwater as melting rates are increased. In addition, the slopes of the linear regression between oxygen and hydrogen for snow with tephra and clean snow are 6.7 and 8, respectively, and the latter is similar to that of the global meteoric water line of 8. Therefore, we can conclude that snow impurities control the isotopic compositions of snow, which is very crucial in the study of climate change and hydrogeology. To quantitatively explain these observations, melting experiments and numerical approaches are required.

• 한국관개배수논문집
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• 제14권2호
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• pp.225-235
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• 2007

The shape of streamflow hydrograph during the early period of spring is very much controlled by the area and depth of snow cover especially in mountainous area. When we simulate the streamfolw of a watershed snowmelt, we need some information for snow cover extent and depth distribution as parameters and input data in the hydrological models. The purpose of this study is to suggest an extraction method of snow cover area and snow depth distribution using Terra MODIS image. Snow cover extent for South Korea was extracted for the period of December 2000 and April 2006. For the snow cover area, the snow depth was interpolated using the snow depth data from 69 meteorological observation stations. With these data, it is necessary to run a hydrological model considering the snow-related data and compare the simulated streamflow with the observed data and check the applicability for the snowmelt simulation.

• 상하수도학회지
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• 제21권3호
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• pp.265-272
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• 2007

This study uses the SWAT model to analyze the characteristics of long-term runoff at the Ssang-cheon Basin located in the city of Sokcho, which is located in the province of Gangwon. The study considers the effect of snow packing and snow melting in a runoff simulation. In this simulation, the study examines the need to introduce a snow pack and snow melt model to evaluate the water resources of the mountainous region of the Gangwon province. The findings of this study indicate that the runoff hydrograph that was produced approximates the true measured flow when the effect of the snow pack and snow melt are considered, compared to when they are not factored in. The analysis of the flow duration curve indicates that the stream flow largely increases when the effect of the snow pack and snow melt are considered. The wet stream flow was shown to increase by nearly 3% due to the melting effect, while the normal stream flow, low stream flow and drought stream flow were shown to increase by slightly more than 10%. Specifically, it was found that as the stream flow decreases, the effect of the snow pack and snow melt on the stream flow increases.

• 한국도로학회논문집
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• 제16권3호
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• pp.67-74
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• 2014

PURPOSES : This study is to investigate the countermeasures against heavy snow on road in Seoul: Focusing on Seocho 1-dong. METHODS : Since 2000, three cases of the top 10 in the highest snow fall depth in a day occurred in 2001(234mm, 156mm) and 2010(258mm) and the possibility of heavy snow is getting higher. 10 days after heavy snow fall when the snow thaws, socio-economic damages occurred often. For example, the insufficient snow removing, difficulty in patients transfer, crash accidents, injuries from a fall, the increasing cost of snow removing etc. RESULTS : For the effective deploying snow removing equipment and workers, it is necessary to understand emergency snow removing spots. Seocho 1-dong was tested because it contains mountains, hill and urban areas as well as various buildings and road types exposures. CONCLUSIONS : Based on the domestic and international heavy snow researches, the elements for vulnerability were analyzed and vulnerable areas to snow fall were derived.

• Wind and Structures
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• 제32권5호
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• pp.453-469
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• 2021

Snow accumulation on the road frequently induces a big traffic problem in the cold snowy region. Accurate prediction on snow distribution is fundamental for solving drifting snow disasters on roads. The present study adopts the transient method to simulate the wind-induced snow distribution on embankment based on the mixture multiphase model and dynamic mesh technique. The simulation and field measurement are compared to confirm the applicability of the simulation. Furthermore, the process of snow accumulation is revealed. The effects of friction velocity and snow concentration on snow accumulation are analyzed to clarify its mechanism. The results show that the simulation agrees well with the field measurement in trends. Moreover, the snow accumulation on the embankment can be approximately divided into three stages with time, the snow firstly deposited on the windward side, then, accumulation occurs on the leeward side which induced by the wake vortex, finally, the snow distribution reaches an equilibrium state with the slope of approximately 7°. The friction velocity and duration have a significant influence on the snow accumulation, and the vortex scale directly affected the snow deposition range on the embankment leeward side.

• 한국농림기상학회지
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• 제22권2호
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• pp.92-101
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• 2020

대설로 인한 시설 농가의 피해를 예방하고 경감시키기 위해서는 기존의 적설 깊이와 더불어 적설하중에 대한 예보가 추가로 제공되어야 한다. 본 연구에서는 눈의 밀도 및 적설하중과 관련하여 해외 연구에서 사용하고 있는 이론과 공식들을 검토하고, 이를 국내에서 장기간의 농업기상관측 이력을 가지고 있는 수원에 적용하여 얻는 적설하중 결과를 소개하였다. 지난 30년(1988~2017) 간 국내 94개 기상대와 무인자동기상 관측소에서 측정된 적설(3시간 신적설, 최심신적설, 최심적설) 깊이 자료를 이용하여 우리나라 대설주의보와 대설경보에 해당하는 적설 깊이의 빈도를 살펴보았다. 우리나라 권역별 적설빈도 공간분포를 보면 대설주의보에 해당하는 신적설은 전북지역에서 많이 발생했고, 대설경보에 해당하는 신적설은 경북과 강원지역에서 많이 나타났다. 기록적인 대설은 경북과 강원지역에서 나타났으나, 최근의 겨울철 대설 피해는 경기, 경북, 전남에서 나타났다. 즉 적설 깊이가 깊더라도 적설하중이 무겁지 않다면 큰 피해가 발생하지 않는 것을 확인할 수 있었다. 수원지역의 적설하중을 추정한 결과를 보면 공식들에 따라 다양한 값들과 특징을 보였다. 대부분 적설 깊이가 깊을 때 적설하중이 무겁게 나타났지만 최대적설하중과 최심적설이 반드시 같은 날에 발생하지는 않았다. 이러한 수원지역의 결과는 다른 지역에서의 적설하중을 추정하는데 도움을 줄 수 있고, 온실구조 설계 기준의 표준 확립과 적설하중 예보를 통해 농가의 경제적 손실을 줄이는데 기여할 것이다.