• 제목/요약/키워드: snow season

검색결과 76건 처리시간 0.022초

Landsat 위성영상을 이용한 킬리만자로 만년설 변화 분석 (Analysis on the Snow Cover Variations at Mt. Kilimanjaro Using Landsat Satellite Images)

  • 박숭환;이명진;정형섭
    • 대한원격탐사학회지
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    • 제28권4호
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    • pp.409-420
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    • 2012
  • 산업혁명 이후 대기 중 이산화탄소 농도는 증가하고 있으며 이는 기후변화로 나타나고 있다. 본 연구에서는 기후변화에 의한 영향을 파악하기 위하여 원격탐사를 이용하여 만년설의 시계열 변화를 정량적으로 분석하고, 종설되는 시점을 통계적으로 예측하고자 한다. 연구지역은 아프리카 탄자니아의 킬리만자로 만년설이다. 1984년 6월부터 2011년 7월까지 전체 27년간 23장의 Landsat-5 TM 및 Landsat-7 ETM+ 자료를 사용하였다. 연구를 위하여 첫째, COST 대기보정 모델을 이용하여 각 영상들의 대기보정을 수행하였다. 둘째, NDSI(Normalized Difference Snow Index) 알고리즘을 이용하여 만년설 면적을 추출하였다. 셋째, SRTM DEM을 이용하여 만년설의 최저고도를 추출하였다. 마지막으로, 일차함수 형태의 추세선을 활용하여 종설 시점을 예측하였다. 분석은 23장 전부를 활용한 것과 건기에 촬영된 17장만을 활용한 것으로 나누어 분석하였다. 분석결과 면적은 27년 동안 약 $9.01km^2$에서 약 $2.54km^2$로 약 $6.47km^2$ 감소하였고, 이는 약 73% 면적의 감소를 의미한다. 최저고도는 27년 동안 약 4,603 m에서 4,893 m로 약 290 m 상승하였다. 추세선을 활용한 결과 면적은 매년 건기에 $0.342km^2$, 전체적으로 $0.421km^2$씩 감소하고 있으며, 최저고도는 매년 건기에 9.848 m, 전체적으로 11.251 m씩 상승하고 있는 것으로 나타났다. 면적 감소량을 통해 종설 시점을 예측한 결과 95% 신뢰도에서 2020년에 완전히 사라질 것으로 분석되었다. 이 연구는 적설지역의 변화를 통하여 전 지구의 기후변화를 모니터링할 수 있다는 근거를 제시했으며, 향후 연구지역 또는 유사 지역의 만년설 현황을 파악하는데 참고 자료로서 활용될 수 있을 것이다.

역사서 검색으로 관찰한 한반도 강설현상 (Snow Falling Phenomenon of the Korean Peninsular Based on the Records of Old Literatures)

  • 김기원;신만용
    • 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.

RWIS 설치를 위한 우선순위 선정 기법에 관한 연구 (A Study of Determining Priorities of RWIS Installation)

  • 양충헌;김인수;전우훈
    • 한국도로학회논문집
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    • 제14권6호
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    • pp.175-182
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    • 2012
  • PURPOSES : This paper presents how to determine priorities of RWIS installation on national highways within the limited budget. METHODS : Analytical hierarchy process was employed to develop the entire methodology. In addition to this, various data such as vulnerable roadway section for snow removal, RWIS, AWS, AADT, and traffic accident were properly collected and analyzed for the future analysis. Then, GIS analysis was performed to find out the final candidate vulnerable roadway section for snow removal. In the end, expert survey was conducted to estimate weights for evaluation criteria. RESULTS : Results showed that metropolitan area has the most high priority, and Gangwon area, ChungCheung, and Honam in order. CONCLUSIONS : The main contribution of this paper is to suggest a logical methodology to prioritize RWIS installation within the limited budget, and thus snow removal operation during the winter season can improve in terms of getting more valuable information.

Differences in Field Sign Abundance of Mammal Species Around the Roads in Baekdudaegan Mountains

  • Hur, Wee-Haeng;Lee, Woo-Shin;Choi, Chang-Yong;Park, Young-Su;Lee, Chang-Bae;Rhim, Shin-Jae
    • 한국산림과학회지
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    • 제94권2호통권159호
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    • pp.112-116
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    • 2005
  • This study was conducted to obtain the information of distribution, protection and management for mammal species in fragmented forest areas around the road from June 2002 to May 2003 in 9 study sites of Baekdugdaegan mountains, Korea. Field signs of twelve mammals, moles Molera robusta, Korean hares Lepus coreanus, Manchurian chipmunk Tamias sibiricus, red squirrels Sciurus vulgaris, Korean racoon dogs Nyctereutes procyonoides, Siberian weasels Mustela sibirica, badgers Meles meles, otters Lutra lutra, Bengal cats Felis bengalensis, wild boars Sus scrofa, water deer Hydropotes inermis and roe deer Capreolus pygargus were recorded in this study. There were no differences in total number of species between 50 m areas and 50-100 m areas from road in snow and non-snow season. Number of mammals' field signs were different in non-snow season between both areas. Red squirrels and Siberian weasels were more abundant in 50 m areas, and Korean hares and Manchurian chipmunks were in 50-100 m areas. Habitat using pattern of mammal species may be affected by the road. Reasonable road construction and maintenance would be needed for protection and management of wildlife and their habitats.

난방.융설 겸용 지열원 히트펌프시스템의 운전성능 평가 (A Performance Estimation of Ground Source Heat Pump System Used both for Heating and Snow-melting)

  • 최덕인;김중헌;황광일
    • 한국지열·수열에너지학회논문집
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    • 제8권1호
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    • pp.7-12
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    • 2012
  • This study proposes a hybrid geothermal system combined with heating mode and snow-melting mode for winter season in order to increase the annual operating efficiency of the GSHP(Ground Source Heat Pump). The purpose of this study is to get effectiveness of the hybrid geothermal system by the site experiments. In case of snow-melting only mode, the GSHP COP is 0.7 higher than system COP in average. And in case of hybrid mode, heating GSHP COP is 0.5 higher than snow-melting GSHP COP. And it is also found out that all COP obtained through measurement periods is higher than nominal COPs given by GSHP manufacturer. As a conclusion, it is clear that the proposed hybrid geothermal system is expected as a highly efficient system.

겨울철 황상 현상의 특징 (The Features Associated with the Yellow Sand Phenomenon Observed in Korea in Wintertime)

  • 전영신;김지영;부경온;김남욱
    • 한국대기환경학회지
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    • 제16권5호
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    • pp.487-497
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    • 2000
  • Spring time is a favorable season to be easily observed the Yellow Sand phenomenon in East Asia. In particular most of the phenomenon tend to occur in April. However, Yellow Sand phenomenon was observed from almost the whole country of Korea in winter of 1966, 1977 and 1999. The features of the synoptic weather pattern in the source regions, air stream flow between the source region and Korea, the measurement of TSP concentration, aerosol size distribution, and chemical composition of snow samples associated with Yellow Sand phenomenon were investigated. The result showed the characteristic evolutionary feature of the synoptic system associated with Yellow Sand phenomena, that is, a strong low level wind mobilized the dust within 2 or 3 days before Yellow Sand phenomenon being observed in Seoul. The wind was remarkably intensified in the source region on January 24, 1999 under the strong pressure gradient, A trajectory analysis showed that the Yellow Sand particle could be reached to Korea within 2 days from the source region, Gobi desert, through Loess plateau and Loess deposition region. The TSP concentration at the top of Kwanak mountain during the Yellow Sand phenomenon is abruptly increasing than the monthly mean concentration. The size resolved number concentration of aerosols ranging from 0.3 to 25${\mu}{\textrm}{m}$ was analyzed during Yellow Sand episode. It was evident that aerosols were distinguished by particles in the range of 2-3 ${\mu}{\textrm}{m}$ to result in the abrupt increase in January 1999, After Yellow Sand phenomenon, there was heavy snow in Seoul. By the analysis of snow collected during that time, it was observed that both the Ca(sup)2+ concentration and pH were increased abnormally compared to those in the other winter season.

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용평 알파인 경기장에서 겨울철 바람의 일변화 및 난류 특성분석 (An Analysis of the Wintertime Diurnal Wind Variation and Turbulent Characteristics over Yongpyong Alpine Slope)

  • 전혜림;김병곤;은승희;이영희;최병철
    • 대기
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    • 제26권3호
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    • pp.401-412
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    • 2016
  • A 3D sonic anemometer has been installed at Yongpyong alpine slope since Oct. 23th 2014 to observe the slope winds and to analyze turbulent characteristics with the change in surface cover (grass and snow) and the synoptic wind strength. Eddy covariance method has been applied to calculate the turbulent quantity after coordinate transformation of a planar-fit rotation. We have carefully selected 3 good episodes in the winter season (23 October 2014 to 28 February 2015) for each category (9 days in total), such as grass and snow covers in case of weak synoptic wind condition, and grass cover of strong synoptic wind. The diurnal variations of the slope winds were well developed like the upslope wind in the daytime and downslope wind in the nighttime for both surface covers (grass and snow) in the weak synoptic forcing, when accordingly both heat and momentum fluxes significantly increased in the daytime and decreased in the nighttime. Meanwhile, diurnal variation of heat flux was not present on the snow cover probably in associated with significant fraction of sunlight reflection due to high albedo especially during the daytime in comparison to those on the grass cover. In the strong synoptic regime, the most dominant feature at Yongpyong, only the southeasterly downslope winds were steadily generated irrespective of day and night with significant increases in momentum flux and turbulent kinetic energy as well, which could suggest that local circulations are suppressed by the synoptic scale forcing. In spite of only one season analysis applied to the limited domain, this kind of an observation-based study will provide the basis for understanding of the local wind circulation in the complex mountain domain such as Gangwon in Korea.

발열 필름을 이용한 제설 기능 PV module & system 제작 및 특성평가 (A Study on the Fabrication and Characteristics of Snow Removal PV Module & System using Heating Film)

  • 박은비;조근영;조성배;김현준;유정재;박지홍
    • Current Photovoltaic Research
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    • 제4권4호
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    • pp.159-163
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    • 2016
  • Piled snow upon PV module interferes with Photoelectric Effect process through photovoltaic directly. As a result of this phenomenon, its generation efficiencies keep decreasing or are stuck at zero power generating status. In addition, PV facilities have been installed on those places such as water surface, roof-top, and other isolated places, dealing with conditions of "Securing high REC weighted value", "Difficulty of securing land" and so forth. Through this study, we are able to actualize the function of heating over PV modules when it snows. We adopted laminating method through heating film and modules, guaranteeing warranty more than for 25 years. Also we are trying remote control systemically, not by hardware control, to run parallel with automatic driving and monitoring system which enable to control operation time, insolation, amount of snowfall automatically. We applied analysis of actual proof to both snow removal PV system and general PV power system, and these led to bear power consumption analysis while snow-removing, and its comparison after finishing the task as "One stone, two birds." In the long run, we could carry out economic analysis against snow removal system, and this helps to verify the most maximized control method for snow removal conditons on a basis of weather information. this study shall let prevent people from negligent accidents, and improve power generation problems as mentioned from the top. Ultimately, we expect to apply this system to heavy snowfall regions in winter season in spite of its limited system installaion in Korean territory, initially.

적설 관측자료 비교를 통한 정량적 SWE 산출에 관한 연구 (A Study of Quantitative Snow Water Equivalent (SWE) Estimation by Comparing the Snow Measurement Data)

  • 노용훈;장기호;차주완;정건희;최지원;하종철
    • 대기
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    • 제29권3호
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    • pp.269-282
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    • 2019
  • While it is important to obtain the accurate information on snowfall data due to the increase in damage caused by the heavy snowfall in the winter season, it is not easy to observe the snowfall quantitatively. Recently, snow measurements using a weighing precipitation gauge have been carried out, but there is a problem that high snowfall intensity results in low accuracy. Also, the observed snowfall data are sensitive depending on wind speed, temperature, and humidity. In this study, a new process of quality control for snow water equivalent (SWE) data of the weighing precipitation gauge were proposed to cover the low accuracy of snow data and maximize the data utilization. Snowfall data (SWE) observed by Pluvio, Parsivel, snow-depth meter using laser or ultrasonic, and rainfall gauge in Cloud Physics Observation Site (CPOS) were compared and analyzed. Applying the QC algorithm including the use of number of hydrometeor particles as reference, the increased SWE per the unit time was determined and the data noise was removed and marked by flag. The SWE data converted by the number concentration of hydrometeor particles are tested as a method to restore the QC-removed data, and show good agreement with those of the weighing precipitation gauge, though requiring more case studies. The three events data for heavy snowfall disaster in Pyeongchang area was analyzed. The SWE data with improved quality was showed a good correlation with the eye-measured data ($R^2$ > 0.73).

한전 765 kV 송전선로 건설을 위한 강원도 태백.사북지역 착빙설 하중조건 검토 (A study on the ice and snow loading condition in Taebaek and Sabuk area in Gangwon province for the construction of KEPCO 765kV transmission lines)

  • 박광희;김용완;원봉주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1923-1924
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    • 1996
  • Some part of the route in KEPCO 765kV transmission line being constructed passes through a high mountain area which is 800m above the sea level (Taebaek, Sabuk area in Gangwon province). This area is the top part of Taebaek mountains corresponding to the backbone of korean peninsula and has lots of snow during the winter season because the winter seasonal wind gone up along the mountainside of Taebaek Mts. meets open air of the East sea. KEPCO has experienced 63 faults of T/L between 1968 and 1993 in this area, which is a very serious problem. Especially 154kV Hwang-Ji T/L fault in 1990, 2 was a unprecedented case which needs to be analyzed carefully to take proper measures. After reviewing ice and snow loading conditions and analyzing the fault of Hwang-Ji T/L, we're going to determine the revisement of ice and snow loading condition in this area to increase reliability of 765kV transmission line.

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