• Title/Summary/Keyword: 몬순

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Comparative Study on Performance of Grid-Connected Photovoltaic Modules in Tropical Monsoon Climate under Thailand condition (태국 열대몬순기후 조건에서 PV모듈 기술별 성능특성 비교 연구)

  • Kim, Seung Duck;Koh, Byung Euk;Park, Jin Hee;Cheon, Dae In
    • New & Renewable Energy
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    • v.10 no.3
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    • pp.39-46
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    • 2014
  • The performances of three different types of photovoltaic (PV) module technologies namely, copper-indium-diselenide (CIGS), mono-crystalline silicon (mo-Si) and amorphous silicon (a-Si) have been comparatively studied in the grid-connected system for more than a year under the tropical monsoon climate of Thailand. The yields, performance ratios and system efficiencies for the respective PV module technologies have been calculated and a comparison is presented here. The performance ratios of the initial operation year for CIGS showed highest among the compared technologies under Thailand climate conditions by marking 97.0% while 89.6% for a-Si and 81.5% for mo-Si. Although mo-Si has shown highest efficiencies all over the period, under the testing conditions, the operating efficiency of mo-Si was down-graded from its reference value mainly due to high operating temperature and the efficiency of the tested CIGS module was also found as high as that of mo-Si in the study. Accordingly, outdoor assessment shows that CIGS modules have demonstrated high performance in terms of yields and performance ratios in Thailand climate conditions.

A Preliminary Investigation on Patterns of Riparian Vegetation Establishment and Typical Cases in Korea (하천식생 활착 유형과 사례의 기초 조사연구)

  • Woo, Hyo-Seop;Park, Moon-Hyeong;Cheong, Sang-Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.474-478
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    • 2009
  • 한반도 하천은 몬순기후와 노년기 지형 등의 영향으로 평상시 물이 흐르는 하도와 충적토로 덮인 주변 사주 및 홍수터를 보여 왔다. 그러나 1970년대 이후 하천이 대규모로 정비, 개발되기 시작하면서 한반도 하천 고유의 '화이트리버'는 점차 식생으로 덮여 '그린리버'로 바뀌게 되었다. 본 연구는 이러한 하천 사주 및 홍수터에 식생이 활착하는 현상에 대해 요인별로 몇 가지 패턴으로 구분하고 대표적인 사례를 제시한다. 패턴 1은 상류 댐, 취수 등 인위적 유황 및 유사이송 변화와 그에 따른 하상 소류력 감소, 홍수터에 신선한 유사퇴적 감소 등으로 식생이 번성하게 되는 경우이다. 패턴 2는 하천개수, 골재채취 등으로 하도가 인위적으로 교란되는 경우이다. 마지막으로 패턴 3은 특히 중소하천에서 비점오염물질(인, 질소) 과다 유입으로 식생이 과다하게 번식하는 경우이나, 아직 현장에서 실제적인 확인은 되어 있지 않다. 이 같은 양상은 어느 하천에서 단독으로 일어날 수도 있고, 복합적으로 일어날 수 있다. 본 조사 연구는 각 양상에 대해서 구체적인 사례를 같이 제시하고, 그 의미를 검토한다.

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Numerical Simulation of the Asian Monsoon for the Mid-Holocene Using a Numerical Model (수치모델을 이용한 홀로세 중기의 아시아 몬순순환 변화 연구)

  • Kim, Seong-Joong;Lee, Bang-Yong;Park, Yoo-Min;Suk, Bong-Chool
    • Ocean and Polar Research
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    • v.27 no.3
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    • pp.289-297
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    • 2005
  • The change in global climate and Asian monsoon patterns during the mid-Holocene, 6000 years before present (6 ka), is simulated by a climate model at spectral truncations of T170 with 18 vertical layers, corresponding to grid-cell sizes of roughly 75km. The present simulation is forced with the observed monthly data of sea surface temperatures, and the specified concentration of atmospheric carbon dioxide, while in the mid-Holocene experiment, orbital parameters such as obliquity, precession, and eccentricity are changed to the 6ka conditions. Under such conditions, the precipitation associated with the summer monsoon is enhanced over a wider zonal band from the Middle East to Southeast Asia, while no significant alteration takes Place in winter. The monsoonal wind also increases over the Arabian Sea, showing the enhanced southwesterly wind during summer and northeasterly wind during winter. Overall, the showing of the Asian monsoon is enhanced during the mid-Holocene, especially in summer, which is consistent with the proxy estimates and other previous model simulations.

Assessment of Large Scale Climate Pattern of Extreme Rainfall in Korea (우리나라 극치강수량 발생시 대규모 기상장 특성 평가)

  • Kwon, Hyun-Han;Kim, Min-Ji;Kim, Jang-Kyung;Kim, Un-Gi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.360-360
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    • 2011
  • 우리나라의 극치강수량 발생 특성은 6~8월 사이에 몬순시스템에 의해 영향을 많이 받는다. 이러한 동아시아 몬순시스템은 대규모 기상학적 거동으로서 우리나라의 국지적 강수발생 특성과 매우 큰 연관성을 가지고 있다. 우리나라의 극치강수량 발생 시에 나타나는 기상학적 특징을 진단하는 과정은 수문 기상학적으로 극치강수량을 예측할 수 있는 기본 토대를 제공할 수 있다. 이러한 점에서 본 연구에서는 우리나라에 발생한 극치강수량을 순위별로 추출하고 각 순위별로 극치강수량 발생시점을 중심으로 5일 이전의 기상변량을 NOAA 재해석(reanalysis) 자료로부터 추출하고 이를 합성시켜 기상특성을 평가하였다. 극치강수량의 기상학적 거동을 평가하기 위한 방법은 다음과 같다. 첫째, 기상변량으로는 Sea Level Pressure, Wind Vector, Geopotential Height 등을 추출한다. 둘째, 이들 기상자료로부터 대규모 강우장만을 추출하기 위해서 기준값(threshold)을 가지고 특정량 이상의 Storm Track만을 추출한다. 셋째, 이들 Storm Track들을 분류하여 범주화 시킨다. 넷째, 범주화된 Storm Track 별로 강수량 분포, 강수지속시간 등에 대한 확률 분포를 유도한다. 또한 이들 Storm Track에 패턴인식 기법을 적용하여 Storm Track의 이동경로를 추정할 수 있는 알고리즘을 개발하고자 한다.

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Drought Assessment Due to Climate Change Using MRI-AM20km: Standardized Precipitation Index (SPI) (MRI-AM20km 자료를 이용한 기후변화에 따른 가뭄 영향 평가: 표준강수지수의 적용)

  • Kim, Kyoung-Jun;Nakakita, Eiich
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.257-257
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    • 2012
  • 본 연구에서는 일본 문부과학성 과제인 혁신(革新, KAKUSHIN)과제를 통해 제공되는 고해상도(20km, 1시간) 기후모형(MRI-AM20km) 출력치를 이용하여 기후변화로 인한 가뭄 발생 특성을 변화를 살펴보았다. 가뭄 특성의 정량화를 위해 표준강수지수를 적용하였으며 일본에서 기록된 주요 가뭄 사상(1980~2001)에 대해 지상 관측 자료 (AMeDAS)를 이용하여 SPI를 산정하고 그 적용성을 파악하였다. 극한가뭄의 거동특성을 파악하기 위해 SPI가 -1.0 이하인 경우를 유효가뭄, -2.0 이하인 경우를 극한가뭄으로 분류하고 가뭄의 강도 및 빈도, 계절적 발생 특성을 파악하였다. 그 결과 대부분의 다른 기후모형과 마찬가지로 MRI-AM20km도 연강수량에 있어서 아시아 몬순 지역 대부분의 국가에서 증가할 것으로 예상하고 있지만, 특히 극한 가뭄의 경우 그 강도 및 빈도가 유의하게 증가할 수 있다는 가능성이 있음을 예상하고 있다. 또한 국가별 가뭄심도-영향면적의 관계를 살펴본 결과 대부분의 아시아 몬순 지역에 대해서 동일한 영향 면적에 대한 가뭄의 강도가 증가하고 지속기간이 증가할수록 그 경향은 더욱 뚜렷하게 나타나는 것을 확인할 수 있었다. 향후 가뭄특성을 지역화하고 대상 지역을 전 세계로 확장하여 가뭄 특성을 정량화할 필요가 있으며, 다양한 모형 출력치를 이용한 결과를 통해 결과의 타당성을 확인할 필요가 있다.

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Simulation Skills of RegCM4 for Regional Climate over CORDEX East Asia driven by HadGEM2-AO (CORDEX 동아시아 지역에서 HadGEM2-AO를 경계조건으로 처방한 RegCM4의 상세 지역기후 모의성능)

  • Oh, Seok-Geun;Suh, Myoung-Seok;Cha, Dong-Hyun;Choi, Suk-Jin
    • Journal of the Korean earth science society
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    • v.32 no.7
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    • pp.732-749
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    • 2011
  • In this study, 27-year (1979-2005) regional climate over the CORDEX East Asia domain was reproduced using a regional climate model, RegCM4, driven by HadGEM2-AO output, and the model's simulation skill was evaluated in terms of surface air temperature and precipitation. The RegCM4 reasonably simulated the spatial distribution and interannual variability and seasonal variability of surface air temperature, while it had systematic biases in the simulation of precipitation. In particular, simulated rainband of East Asian summer monsoon was southward shifted below $30^{\circ}N$ as compared with the observation, thereby, summer mean precipitation over South Korea was significantly underestimated. Simulated temperature from the RegCM4 driven by the HadGEM2-AO output was comparable to that driven by the reanalysis. However, the RegCM4 driven by the HadGEM2-AO had prominently poor skill in the simulation of precipitation. This can be associated with the distorted monsoon circulations in the driving data (i.e., HadGEM2-AO) such as southward shifted low-level southwesterly, which resulted in the erroneous evolution of East Asian summer monsoon simulated by RegCM4.

Spatial and Temporal Variation of Macroinvertebrates according to Physical Factors in Gongji Stream Area (공지천 수계에서 물리적인 요인에 따른 저서성 대형무척추동물 군집의 시.공간적인 변동)

  • Lee, Jaeyong;Lee, Kwang-Yeol;Han, Sang-Jin;Lee, Seok-Jong;Jung, Yukyong;Cheon, Jaelyoung;Choi, Jaeseok;Kim, Joon Chul
    • Korean Journal of Environment and Ecology
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    • v.28 no.1
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    • pp.24-32
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    • 2014
  • Our study is purposed to understand effect on spatio-temporal variability of macroinvertebrate community 11 sampling times at 4 sites between two streams (Shinchon stream and Gongji stream in Chuncheun City) from May 2011 to October 2013. In this study, the possible physical factors on spatio-temporal variability of macroinvertebrate community were discussed. After stream improvement project, the effects of anthropogenic disturbance in study sites appeared as increased water temperature more than $30^{\circ}C$ and the difference of water temperature between Shinchon stream and Gongji stream was by maximum $9^{\circ}C$ on 2012. The monsoon rainfall decreased number of species, individuals and biodiversity index of macroinvertebrate community, particularly, in Shincheon stream compare to Gongji stream. Dominant species of macroinvertebrate taxa was caddisfly in Shincheon stream and Diptera in Gongji stream but on August 2013, it was dominated by Diptera, Chironomidae spp. in all study sites. The spatio-temporal variability of macroinvertebrate community in the streams may be useful as bio-indicator influencing anthropogenic factors such as soil erosion (landslide or cultivation) or monsoon rainfall.

Characterization of Convective Weather Systems in the Middle Himalaya during 1999 and 2000 Summer Monsoons (1999년과 2000년 여름몬순기간 동안 히말라야 지역에 발생한 대류계의 특성에 관한 연구)

  • Kim, Gwang-Seob;Noh, Joon-Woo
    • Journal of Korea Water Resources Association
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    • v.36 no.3 s.134
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    • pp.495-505
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    • 2003
  • Convective weather systems such as organized mesoscale convective systems (Mesoscale Convective Complex, MCC and Convective Cloud Clusters, CCC) and much weaker Disorganized Short-lived Convection (DSC) in the region of India and Nepal were analyzed using the Meteosat-5 IR imagery. The diurnal march and propagation of patterns of convective activity in the Himalayas and Northern Indian subcontinent were examined. Results indicate that infrared satellite images of Northern India and along the southern flank of the Himalayas reveal a strong presence of convective weather systems during the 1999 and 2000 monsoons, especially in the afternoon and during the night. The typical MCCs have life-times of about 11 hours, and areal extent about $300,000km^2$. Although the core of MCC activity remains generally away from the Middle Himalayan range, the occurrence of heavy precipitation events in this region can be directly linked to MCCs that venture into the Lesser Himalayan region and remain within the region bounded by $25^{\circ}-30^{\circ}N$. One principal feature in the spatial organization of convection is the dichotomy between the Tibetan Plateau and the Northern Indian Plains: CCCs and DSCs begin in the Tibetan Plateau in the mid-afternoon into the evening; while they are most active in the mid-night and early morning in the Gangetic Plains and along the southern facing flanks of the Himalayas. Furthermore, these data are consistent with the daily cycle of rainfall documented for a network of 20 hydrometeorological stations in Central Nepal, which show strong nocturnal peaks of intense rainfall consistent with the close presence of Convective Weather Systems (CWSs) in the Gangetic Plains (Barros et al. 2000).

Methane Gas Emission from an Artificial Reservoir under Asian Monsoon Climate Conditions, with a Focus on the Ebullition Pathway (아시아 몬순 기후지역에 위치한 대형 인공호에서 기포형태로의 메탄 (CH4) 가스 배출량)

  • Kim, Kiyong;Jung, Sungmin;Choi, Youngsoon;Peiffer, Stefan;Knorr, Klaus-Holger;Kim, Bomchul
    • Korean Journal of Ecology and Environment
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    • v.51 no.2
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    • pp.160-167
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    • 2018
  • The role played by reservoirs in the biogeochemical cycles of elements is a subject of ongoing debate. Recent research has revealed that reservoirs emit significant levels of greenhouse gases. To assess the importance of reservoirs in monsoon climate areas as a source of methane gas into the atmosphere, we investigated variations in organic carbon (OC) input into the reservoir, oxic state changes, and finally the amount of methane emitted (focusing on the ebullition pathway) in Lake Soyang, which is the largest reservoir in South Korea. Total organic carbon (TOC) concentrations were higher during summer after two years of heavy rainfall. The sedimentation rates of particulate organic carbon (POC) and particulate organic nitrogen (PON) were higher in the epilimnion and hypolimnion than the metalimnioin, indicating that autochthonous and allochthonous carbon made separate contributions to the TOC. During stratification, oxygen depletion occurred in the hypolimnion due to the decomposition of organic matter. Under these conditions, $H_2S$ and $CH_4$ can be released from sediment. The methane emissions from the reservoir were much higher than from other natural lakes. However, the temporal and spatial variations of methane ebullition were huge, and were clearly dependent on many factors. Therefore, more research via a well-organized field campaign is needed to investigate methane emissions.