• 제목/요약/키워드: Climatic Changes

검색결과 319건 처리시간 0.021초

Simulation of Daily Soil Moisture Content and Reconstruction of Drought Events from the Early 20th Century in Seoul, Korea, using a Hydrological Simulation Model, BROOK

  • Kim, Eun-Shik
    • Journal of Ecology and Environment
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    • 제33권1호
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    • pp.47-57
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    • 2010
  • To understand day-to-day fluctuations in soil moisture content in Seoul, I simulated daily soil moisture content from 1908 to 2009 using long-term climatic precipitation and temperature data collected at the Surface Synoptic Meteorological Station in Seoul for the last 98 years with a hydrological simulation model, BROOK. The output data set from the BROOK model allowed me to examine day-to-day fluctuations and the severity and duration of droughts in the Seoul area. Although the soil moisture content is highly dependent on the occurrence of precipitation, the pattern of changes in daily soil moisture content was clearly quite different from that of precipitation. Generally, there were several phases in the dynamics of daily soil moisture content. The period from mid-May to late June can be categorized as the initial period of decreasing soil moisture content. With the initiation of the monsoon season in late June, soil moisture content sharply increases until mid-July. From the termination of the rainy season in mid-July, daily soil moisture content decreases again. Highly stochastic events of typhoons from late June to October bring large amount of rain to the Korean peninsula, culminating in late August, and increase the soil moisture content again from late August to early September. From early September until early October, another sharp decrease in soil moisture content was observed. The period from early October to mid-May of the next year can be categorized as a recharging period when soil moisture content shows an increasing trend. It is interesting to note that no statistically significant increase in mean annual soil moisture content in Seoul, Korea was observed over the last 98 years. By simulating daily soil moisture content, I was also able to reconstruct drought phenomena to understand the severity and duration of droughts in Seoul area. During the period from 1908 to 2009, droughts in the years 1913, 1979, 1939, and 2006 were categorized as 'severe' and those in 1988 and 1982 were categorized as 'extreme'. This information provides ecologists with further potential to interpret natural phenomenon, including tree growth and the decline of tree species in Korea.

1KM NDVI 10년 자료를 이용한 한반도 식생의 경년변동 분석 (Vegetation Interannualvariavility Over Korea Using 10-Years 1KM NDVI Data)

  • 김인환;한경수;김상일
    • 대한원격탐사학회지
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    • 제27권1호
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    • pp.17-24
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    • 2011
  • 지구온난화는 인간의 생활과 해양 생태계에 영향을 미치며 또한 기후 시스템에 변화를 야기 시키며 전 지구 기후 변화를 가속화 시킨다. 이에 기후변화에 민감하게 반응하는 식생의 변화를 분석하는 일은 매우 중요하다. 푸리에 변환에 기초한 조화분석은 주기를 가지는 시계열 자료를 효과적으로 논증할 수 있는 방법이다. 특히, 식생은 1년을 주기로 계절에 따라 성장과 쇠퇴를 반복하기 때문에 조화분석을 이용한 분석에 매우 적합한 연구 대상이다. 조화분석을 통해 추출한 주기 성분은 시간에 흐름에 따른 식생의 변화를 개괄적으로 분석할 수 있다. 따라서 본 연구에서는 SPOT/VEGETATION S10 MVC NDVI와 MODIS Land Cover Map 자료를 이용하여 토지 피복을 재 분류하고 지난 10년간 한반도 식생의 변화를 조화분석의 1주기 성분을 통해 분석하였다. 조화분석으로부터 추출 된 성분을 선형회귀 분석을 이용하여 변화 정도를 관찰한 결과 Cropland는 1년에 0.5일, Forest의 경우 1년에 0.8 일씩 성장 곡선의 주기가 빨라지고 있었다. 분석 된 자료는 한반도의 장기간 식생의 변화를 효과적으로 분석할 수 있는 방법으로 사료된다.

침수흔적도를 활용한 침수지역 유형화에 관한 연구 -부산광역시를 사례로- (A Study on Flood Area Typology Using the Inundation Trace Map - A Case Study of Busan Metropolitan City -)

  • 유창주;홍순헌;최현;남광우
    • 한국측량학회지
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    • 제31권5호
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    • pp.393-400
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    • 2013
  • 최근 기후변화에 따른 국지성 집중호우나 홍수로 인해 침수피해, 환경파괴 등 인명피해나 재산피해가 증가하고 있는 추세이다. 특히, 도시의 난개발로 인한 불투수율 증가로 인해 침수 빈도 증가와 함께 침수지역의 확대로 인한 많은 재산피해가 발생하고 있다. 이에 본 연구에서는 2009년부터 구축된 부산지역의 침수흔적도를 이용하여 부산광역시의 해운대구, 수영구, 사하구를 대상으로 침수지역의 유형화를 통해 각 유형별 침수피해 원인 분석 및 방지 대책을 제시하였다. 이를 위해 침수지역을 내수범람형, 하천범람형, 해수범람형으로 분류한 후 사전예방 중심의 방지대책을 관리체계 측면, 인프라 구축 측면, 시스템 측면으로 나누어 관련성을 부여함으로써 보다 더 객관적이고 과학적으로 침수문제에 접근하였고 이러한 연구를 통해 추후 침수흔적도의 활용에 관한 활성화 방안을 제시하였다.

Modelling land surface temperature using gamma test coupled wavelet neural network

  • Roshni, Thendiyath;Kumari, Nandini;Renji, Remesan;Drisya, Jayakumar
    • Advances in environmental research
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    • 제6권4호
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    • pp.265-279
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    • 2017
  • The climate change has made adverse effects on land surface temperature for many regions of the world. Several climatic studies focused on different downscaling techniques for climatological parameters of different regions. For statistical downscaling of any hydrological parameters, conventional Neural Network Models were used in common. However, it seems that in any modeling study, uncertainty is a vital aspect when making any predictions about the performance. In this paper, Gamma Test is performed to determine the data length selection for training to minimize the uncertainty in model development. Another measure to improve the data quality and model development are wavelet transforms. Hence, Gamma Test with Wavelet decomposed Feedforward Neural Network (GT-WNN) model is developed and tested for downscaled land surface temperature of Patna Urban, Bihar. The results of GT-WNN model are compared with GT-FFNN and conventional Feedforward Neural Network (FFNN) model. The effectiveness of the developed models is illustrated by Root Mean Square Error and Coefficient of Correlation. Results showed that GT-WNN outperformed the GT-FFNN and conventional FFNN in downscaling the land surface temperature. The land surface temperature is forecasted for a period of 2015-2044 with GT-WNN model for Patna Urban in Bihar. In addition, the significance of the probable changes in the land surface temperature is also found through Mann-Kendall (M-K) Test for Summer, Winter, Monsoon and Post Monsoon seasons. Results showed an increasing surface temperature trend for summer and winter seasons and no significant trend for monsoon and post monsoon season over the study area for the period between 2015 and 2044. Overall, the M-K test analysis for the annual data shows an increasing trend in the land surface temperature of Patna Urban.

논문 - 기후변화에 따른 농업생산기반 재해 취약성 평가를 위한 대리변수 선정 (The Proxy Variables Selection of Vulnerability Assessment for Agricultural Infrastructure According to Climate Change)

  • 김성재;박태양;김성민;김상민
    • 한국관개배수논문집
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    • 제18권2호
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    • pp.33-42
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    • 2011
  • Climate change has impacts on not only the average temperature rise but also the intensity and frequency of extreme events such as flood and drought. It is also expected that the damages on agricultural infrastructure will be increased resulting from increased rainfall intensity and frequency caused by climate change. To strengthen the climate change adaptation capacity, it is necessary to identify the vulnerability of a given society's physical infrastructures and to develop appropriate adaptation strategies with infrastructure management because generally facilities related to human settlements are vulnerable to climate changes and establishing an adaptive public infrastructure would reduce the damages and the repair cost. Therefore, development of mitigation strategies for agricultural infrastructure against climatic hazard is very important, but there are few studies on agricultural infrastructure vulnerability assessment and adaptation strategies. The concept of vulnerability, however, is difficult to functionally define due to the fact that vulnerability itself includes many aspects (biological, socioeconomic, etc.) in various sectors. As such, much research on vulnerability has used indicators which are useful for standardization and aggregation. In this study, for the vulnerability assessment for agricultural infrastructure, 3 categories of climate exposure, sensitivity, and adaptation capacity were defined which are composed of 16 sub-categories and 49 proxy variables. Database for each proxy variables was established based on local administrative province. Future studies are required to define the weighting factor and standardization method to calculate the vulnerability indicator for agricultural infrastructure against climate change.

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Importance and production of chilli pepper; heat tolerance and efficient nutrient use under climate change conditions

  • Khaitov, Botir;Umurzokov, Mirjalol;Cho, Kwang-Min;Lee, Ye-Jin;Park, Kee Woong;Sung, JwaKyung
    • 농업과학연구
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    • 제46권4호
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    • pp.769-779
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    • 2019
  • Chilli peppers are predominantly cultivated in open field systems under abiotic and biotic stress conditions. Abiotic and biotic factors have a considerable effect on plant performance, fruit quantity, and quality. Chilli peppers grow well in a tropical climate due to their adaptation to warm and humid regions with temperatures ranging from 18 to 30℃. Nowadays, chilli peppers are cultivated all around the world under different climatic conditions, and their production is gradually expanding. Expected climate changes will likely cause huge and complex ecological consequences; high temperature, heavy rainfall, and drought have adverse effects on the vegetative and generative development of all agricultural crops including chilli peppers. To gain better insight into the effect of climate change, the growth, photosynthetic traits, morphological and physiological characteristics, yield, and fruit parameters of chilli peppers need to be studied under simulated climate change conditions. Moreover, it is important to develop alternative agrotechnologies to maintain the sustainability of pepper production. There are many conceivable ideas and concepts to sustain crop production under the extreme conditions of future climate change scenarios. Therefore, this review provides an overview of the adverse impacts of climate change and discusses how to find the best solutions to obtain a stable chilli pepper yield.

Differences in Temporal Variation of Ground Beetle Assemblages (Coleoptera: Carabidae) between Two Well-Preserved Areas in Mt. Sobaeksan National Park

  • Jung, Jong-Kook;Suk, Sang-Wook;Kim, Byeong-Young;Hong, EuiJeong;Kim, Youngjin;Jeong, Jong-Chul
    • Journal of Forest and Environmental Science
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    • 제33권2호
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    • pp.122-129
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    • 2017
  • Understanding how future climate conditions will be impact on the biodiversity and species composition is important, because biodiversity becomes more important in environment assessment. To understand the biological changes including diversity and species composition over time (temporal variation within a year), the species diversity and composition of ground beetles were investigated in two well-preserved areas in the Sobaeksan National Park using pitfall traps. In addition, relationships between ground beetles and environmental variables were studied by considering temporal variation. We collected 2,146 ground beetle specimens representing 45 species, and individual-based rarefaction curves indicated that similar species richness was found between Geumseon Valley (GV) and Namcheon Valley (NV). The Bray-Curtis matrix comparisons between study sites were characterized by similar ground beetles sample heterogeneity, while temporal variations in abundance, species richness, and ${\beta}-diversity$ of ground beetles showed rather difference over time according to location of study sites. In GV site, minimum temperature was selected as the best predictor for abundance, species richness, and ${\beta}-diversity$ of ground beetles, while those relationships in NV site were more complicated. In conclusion, our study suggests that understanding the different response of ground beetles to climatic variables related to local habitat conditions is important to predict the effect of climate change on biological communities.

신체의 부위별 피복이 체온조절 및 주관적인 감각에 미치는 영향(II) (Effects of Covering Parts of Body with Garments on Human Thermoregulation and Sensation(II))

  • 이종민
    • 한국의류학회지
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    • 제18권3호
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    • pp.339-347
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    • 1994
  • In this study the physiological significance of the upper and lower body on thermoregulation and sensation are examined. Experiments were carried out on 4 females in a climatic chamber conditioned at $25\pm1^{circ}C, 50\pm5%$ R.H.. Before the measurements, subjects were exposed to 3 types of enviromental temperature: 1) $25\pm1^{\circ}C$ for 60 min.(ST), 2) $25^{\circ}C$\rightarrow35^{circ}C\rightarrow25^{\circ}C$ for about 40 min.(HT), 3) $25^{\circ}C$\rightarrow15^{circ}C\rightarrow25^{\circ}C$ for about 40 min.(LT) covering the upper body (U) or lower body (L) with garments. 1) $T_{re}$ was significantly higher in L than in U only in 57 condition. $T_{sk}$ and Temp. under the clothing were higher in U than in L in all three conditions. Thermal sensation was warmer in U than in L, and comport sensation was most comfortable in HT condition. 2) When the upper or lower body was covered or exposed, the mean skin temperature of the upper body was higher than that of the lower body. Following covering and uncovering the same area, the changes in skin temperature were greater in the upper body than in lower body, and covering the upper body produced a greater difference of skin temperature between body and lower body than covering the lower body. 3) In all environmental conditions, when the upper body was uncovered, the skin temperatures of the chest, upper arms and forearms dropped to a considerable degree, and when the lower body was uncovered, skin temperatures of the legs showed the same pattern. On the other hand, skin temperature of the thinghs showed only little change in all cases except forehead and back uncovered or covered in two clothing types.

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옥상공간의 태양광 자원 해석을 통한 PV 시스템 및 녹화식재에 대한 적지조건분석 (The Analysis of Optimal Site Condition for Photovoltaic System and Green Roof Planting through Sunlight Component Simulation of Rooftop Area)

  • 김태한;박대근;권지영
    • 한국환경복원기술학회지
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    • 제16권4호
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    • pp.27-40
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    • 2013
  • These day morden cities have serious climatic problems due to enviornmental load caused by excessive development of urbanization. As technological improvement to answer to various ecological disasters and climate changes are also called on the field of construction, inter-disciplinary studies linked to the estabilishment of sustainable energy generation systems and enviornmental control is needed in a consilient point of view. This study aims to analyse optimal site conditions for photovoltaic system and green roof planting through solar radiation simulation in a integrated perspective. In so doing, it seeks to proffer basic study for developing a sound use of roof area that is sustainable in environmental and resources aspects. A computer simulation showed that, in the case of total seasonal solar radiation, summer season resulted 312.5kWh in 35% of total annual solar radiation. This season indicated the lowest radiation rate of the year for direct sunlight in 45.8% of total seasonal solar radiation. Due to such solar radiation simulation, at the largest optimal planting area, Glechoma hederacea var. longituba secured $719.16m^2$ of gross roof area.

융기가 기반암 하상하천의 종단곡선에 미치는 영향에 대한 연구 -수리 모형을 통한 연구- (Influence of Tectonic Uplift on Longitudinal Profiles of Bedrock Rivers: Numerical Simulations)

  • 김종연
    • 대한지리학회지
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    • 제39권5호
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    • pp.722-734
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    • 2004
  • 기반암 하상 하천의 종단 곡선은 지형 경관 발달의 기본 조건을 형성함으로서 경관 변화에 강력한 영향을 행사한다. 하천 종단 곡선은 기후 환경 조건의 변화, 기반암의 물리 화학적 특성, 지각 운동과 같은 변수들에 의해서 그 형태의 변화를 경험하게 된다. 특히 지각 운동의 시 공간적 양상은 지각 운동이 활발한 혹은 활발했던 것으로 알려진 지역에서 종단곡선에 강력한 영향력을 행사하는 것으로 추론되어 왔다. 그러나, 현재까지의 기반암 하상 하천에 대한 연구는 기반암 하상 하천의 침식 작용을 통제하는 변수들에 대한 이해의 부족으로 답보상태를 면하지 못하여 왔다. 현대 지형학의 주요 연구 기법인 컴퓨터를 이용한 지형 발달 시뮬레이션은 지형 발달의 단계들을 파악하는데 유용한 연구 도구로 환용 되어 왔으나. 기반암 하상 하천의 경우 그 이해의 부족으로 인하여 광범위한 응용이 가능한 모형의 마련에 어려움을 겪어 왔다. 그 결과 기존의 연구들은 단순한 확산 모형을 침식의 기본 모형으로 이용했다. 본 고 에서는 물리적 침식과정에 기반한 기반암 침식 모형들을 검토 수정한 새로운 모형을 소개하고 해당 모형을 이용하여 지각운동의 시 공간적 분포와 강도가 하천 종단 곡선에 미치는 영향을 시뮬레이션을 통해 모사하고 논의하였다.