• 제목/요약/키워드: Tropical Night

검색결과 59건 처리시간 0.028초

Evaluating Tropical Night by Comparing Trends of Land cover and Land Surface Temperature in Seoul, Korea

  • Sarker, Tanni;Huh, Jung Rim;Bhang, Kon Joon
    • 한국측량학회지
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    • 제38권2호
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    • pp.123-130
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    • 2020
  • The impact of urbanization on LST (Land Surface Temperature) and TN (Tropical Night) was observed with the analyses of land cover change and LST by associating with the frequency of TN during the period of 1996 to 2016. The analyses of land cover and LST was based on the images of Landast 5 and 8 for September in 1996, 2006, and 2016 at a 10 year interval. The hourly-collected atmospheric temperatures for the months of July and August during the period were collected from AWSs (Automatic Weather Stations) in Seoul for the frequency analysis of TN. The study area was categorized into five land cover classes: urban or built-up area, forest, mixed vegetation, bare soil and water. It was found that vegetation (-7.71%) and bare soil (-9.04%) decreased during the period while built-up (17.29%) area was expanded throughout the whole period (1996-2016), indicating gradual urbanization. The changes came along with the LST rise in the urban area of built-up and bare soil in Seoul. In addition, the frequency of TN has increased in 4.108% and 7.03% for July and August respectively between the two periods of the 10 year interval, 1996-2006 and 2006-2016. By comparing the increasing trends of land cover, LST, and TN, we found a high probability that the frequency of TN had a relationship with land cover changes by the urbanization process in the study area.

우리나라 열대야 현상 발생의 시.공간적 특징과 최근의 변화 (Spatial-Temporal Patterns and Recent Changes of Tropical Night Phenomenon in South Korea)

  • 최광용;권원태
    • 대한지리학회지
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    • 제40권6호
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    • pp.730-747
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    • 2005
  • 본 연구에서는 우리나라에서 야간의 시간진행에 따라 발생하는 열대야 현상의 평균적인 시${\cdot}$공간적 패턴과 기후인자와의 관련성 그리고 최근의 변화경향을 밝히고자 하였다. 이를 위해, 장기간(1973-2004) 우리나라 61개 관측지점의 야간 6시간별(9PM, 3AM) 기온 및 일 최저기온 자료를 바탕으로 각 시간대별 열대야 현상의 평균 발생빈도를 산출하였다. 시간적으로, 우리나라 열대야현상은 연중 여름철 장마휴지기(7월 하순-8월 초순)에 집중하여 발생하며, 저녁(9PM)열대야 현상이 심야(3AM)나 새벽열대야 현상에 비해 많이 발생한다. 공간적으로, 저녁열대야 현상이 도시열섬 현상으로 저위도 내륙의 대도시에서 많이 발생하는 반면, 심야열대야 현상과 새벽열대야 현상은 따뜻한 해양의 열 관성의 영향을 받는 해양으로부터 30km이내 해안가 지역을 따라서 많이 발생한다. 대조적으로, 저녁(새벽)열대야 현상은 고도상승에 따른 기온감률 때문에 태백${\cdot}$소백 산맥의 해발고도가 800m(300m)이상이 되는 고지대에서는 전혀 발생하지 않는다. 상관분석과 다중회귀분석 결과, 위도, 해발고도, 해양과의 인접성, 인구밀도 등의 자연적${\cdot}$인위적 기후인자는 야간에 시각에 따라 열대야 현상의 발생빈도에 다양하게 영향을 주고 있음이 밝혀졌다. 또한, 1990년 이후에는 이전에 비하여 늦장마 시기의 변화와 도시화의 심화로 인해 열대야 현상의 발생빈도가 주로 대도시를 중심으로 증가하였다. 따라서, 차후에는 인위적으로 증가하는 도시열대야 현상을 저감시키기 위한 대책이 마련되어야 할 것이다.

대구시 열대야 대응 구역 설정을 위한 야간 찬공기 유동성 분석 (Analysis of Nocturnal Cold Air Flow Characteristics for Setting of Tropical Night Response Zone in Daegu)

  • 서보용;이상범;권순범;차재규;정응호
    • 한국지리정보학회지
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    • 제23권3호
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    • pp.220-235
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    • 2020
  • 도시에서의 폭염발생은 기본적으로 지구온난화에 영향을 받으나, 도시에서 발생하는 인공열 배출과 열축적이 큰 토지피복의 영향으로 더욱 가중된다. 특히 도시폭염의 영향은 야간 열대야 발생에도 직접적 영향을 준다. 그러나 기본적으로 주간의 폭염대응에 비해 열대야 대응수단 선택은 매우 제한적이다. 본 연구에서는 대구시를 대상으로 열대야 대응 방안으로 야간 찬공기 유동 특성을 분석하고 이의 공간적 활용가능성을 제시하고자 하였다. 연구방법은 찬공기 유동 분석 프로그램인 KLAM_21을 활용하여 대구시의 찬공기 유동의 공간적 특성인 찬공기 높이 및 유동범위와 유속 및 유동방향을 정량적으로 분석하였다. 분석결과 대구시 주변산지에서의 찬공기 생성, 유동은 매우 활발하나 열대야 발생지역인 도심지역으로 유입이 제한적인 것으로 나타났다. 그러나 일부 시가지에서는 주변산지로부터 유입되는 찬공기 유동성이 매우 활발하여 열대야 대응에 매우 효과적인 공간적 조건을 가지고 있는 것으로 나타났다. 이러한 공간적 조건을 도시계획적 차원에서 활용하면 열대야 대응방안 개발에 매우 유용할 것으로 판단된다.

대구의 장기적 도시기후 변동에 관한 연구 (Study on the Long-term Change of Urban Climate in Daegu)

  • 김해동
    • 한국환경과학회지
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    • 제12권7호
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    • pp.697-704
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    • 2003
  • Through data analysis using the meteorological data during 40 years(1961∼2000) for 2 stations(Daegu and Chupungnyong), we studied the present condition and long-term trends in urban climatic environments of Daegu. It was found that there was about 1.5$^{\circ}C$ rise in annual mean temperature of Daegu from 1961 to 2000. On the other hand, that of Chupungnyung was not more than 0.4$^{\circ}C$ for the same period. The regional disparity in temperature changes has been caused by the difference of urban effects on climate between two regions. In particular, the urban warming appears more significant in winter season. There was about 3$^{\circ}C$ rise in annual mean daily minimum temperature of winter season(Dec.∼Feb.) in Daegu. As the result, the number of winter days continuously decreased from 115 days(1961) to 75 days(2000). The long-term trends of relative humidity were also studied to exame the effects of urbanization on climate in Daegu. It was found that there was about 7% decrease in relative humidity of Daegu during past 40 years(1961∼2000). On the other side, the decrease of Chupungnyung was not more than 2% for the same period. The long-term trends of the other climatic factors(fog days, tropical night days, etc) were also studied in this study.

여름철 열대야 발생시 탑상형 아파트의 실내온열환경에 대한 연구 (A Study on Indoor Thermal Environment in an Tower Type Apartment House at Tropical Nights)

  • 장현재;김형진
    • 설비공학논문집
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    • 제22권1호
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    • pp.20-25
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    • 2010
  • In this study, As a basic research for improving indoor thermal environment at tower type apartment houses, specifications of heat storage and heat emission in the structures of apartment houses were investigated, and the ratio of indoor and outdoor air velocity at tower type apartment house was examined, too. Indoor temperature at night time was higher than outdoor air temperature because heat emission from the structure of wall, ceiling and floor those are constructed by use of reinforced concrete which has large heat capacity. The ratio of indoor and outdoor air velocity was lower than 0.1 and this was caused by the plan of tower type apartment house. PMV was in the range of 0.3~1.9, and was about 1.0 (it means slightly warm) at 10 : 00 p.m.. To improve indoor thermal environment in summer season at tower type apartment houses, it needs more investigation on specifications of heat storage and heat emission in the structure including winter season, and on the improvement of the ratio of indoor and outdoor air velocity.

야간온도 변화에 따른 망고 'Irwin'의 개화, 과실특성 및 수체생육 (Flowering, Fruit Characteristic and Shoot Growth of the Mango, cv. 'Irwin' in Response to D ifferent Night Temperature)

  • 임찬규;안현주;전미경;김설아;정선우
    • 한국농림기상학회지
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    • 제23권4호
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    • pp.349-355
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    • 2021
  • 본 연구는 꽃눈발아기부터 과실비대기까지 야간온도의 조정이 망고 'Irwin' 품종의 개화, 과실특성 및 수체생육에 미치는 영향을 조사함으로써 망고 재배를 위한 적정 야간온도를 구명하고 시설하우스 내부의 온도관리 방안을 모색하고자 수행하였다. 야간온도 처리에 따른 개화기, 만개기, 착과기, 성숙기 그리고 수확기는 온도가 높을수록 빨라지는 경향을 보였다. 꽃대길이는 야간온도가 10℃일때 가장 짧았으며 온도가 높을수록 생육이 좋아졌으나 15℃와 20℃의 처리간에는 유의차는 없었다. 과실 종경과 무게는 야간온도가 15℃와 20℃가 10℃보다 높게 나타났으며 가용성고형물함량(SSC)와 산함량(TA)은 야간온도 처리간에 차이를 보이지 않았다. 그리고 과실의 경도와 과피의 색도는 야간온도가 높을수록 높게 나타났다. 과실 수확이 끝나고 전정을 한 이후 발생한 가지의 생육은 처리간 유의차를 보이지 않았다. 따라서 망고의 시설하우스 재배 시 과실의 수량을 높이고 고품질 과실을 생산하기 위해서는 야간 최저온도를 15℃ 또는 20℃로 설정하는 것이 적절하며 난방비 절감을 위해서는 야간 최저온도를 15℃로 설정하여 재배하는 것이 바람직한 것으로 판단된다.

Extracorporeal Worm Extraction of Diphyllobothrium nihonkaiense with Amidotrizoic Acid in a Child

  • Shin, Hye Kyung;Roh, Joo-Hyung;Oh, Jae-Won;Ryu, Jae-Sook;Goo, Youn-Kyoung;Chung, Dong-Il;Kim, Yong Joo
    • Parasites, Hosts and Diseases
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    • 제52권6호
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    • pp.677-680
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    • 2014
  • Infection cases of diphyllobothriid tapeworms are not much in the below teen-age group. We report a case of Diphyllobothrium nihonkaiense infection in a 13-year-old boy. He presented with severe fatigue, occasional abdominal pain at night time. He also had several episodes of tapeworm segment discharge in his stools. By his past history, he had frequently eaten raw fish including salmon and trout with his families. Numerous eggs of diphyllobothriid tapeworm were detected in the fecal examination. We introduced amidotrizoic acid as a cathartic agent through nasogastroduodenal tube and let nearly whole length (4.75 m) of D. nihonkaiense be excreted through his anus. After a single dose of praziquantel, the child's stool showed no further eggs, and his symptoms disappeared. The evacuated worm was identified as D. nihonkaiense by mitochondrial cox1 gene analysis. Here we report a successful extracorporeal worm extraction from an infection case of D. nihonkaiense by the injection of amidotrizoic acid.

Three-dimensional Numerical Prediction on the Evolution of Nocturnal Thermal High (Tropical Night) in a Basin

  • Choi, Hyo;Kim, Jeong-Woo
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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    • 제25권1호
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    • pp.57-81
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    • 1997
  • Numerical prediction of nocturnal thermal high in summer of the 1995 near Taegu city located in a basin has been carried out by a non-hydrostatic numerical model over complex terrain through one-way double nesting technique in the Z following coordinate system. Under the prevailing westerly winds, vertical turbulent fluxes of momentum and heat over mountains for daytime hours are quite strong with a large magnitude of more than $120W/\textrm{m}^2$, but a small one of $5W/\textrm{m}^2$ at the surface of the basin. Convective boundary layer (CBL) is developed with a thickness of about 600m over the ground in the lee side of Mt. Hyungje, and extends to the edge of inland at the interface of land sea in the east. Sensible heat flux near the surface of the top of the mountain is $50W/\textrm{m}^2$, but its flux in the basin is almost zero. Convergence of sensible heat flux occurs from the ground surface toward the atmosphere in the lower layer, causing the layer over the mountain to be warmed up, but no convergance of the flux over the basin results from the significant mixing of air within the CBL. As horizontal transport of sensible heat flux from the top of the mountain toward over the basin results in the continuous accumulation of heat with time, enhancing air temperature at the surface of the basin, especially Taegu city to be higher than $39.3^{\circ}C$. Since latent heat fluxes are $270W/\textrm{m}^2$ near the top of the mountain and $300W/\textrm{m}^2$ along the slope of the mountain and the basin, evaporation of water vapor from the surface of the basin is much higher than one from the mountain and then, horizontal transport of latent heat flux is from the basin toward the mountain, showing relative humidity of 65 to 75% over the mountain to be much greater than 50% to 55% in the basin. At night, sensible heat fluxes have negative values of $-120W/\textrm{m}^2$ along the slope near the top of the mountain and $-50W/\textrm{m}^2$ at the surface of the basin, which indicate gain of heat from the lower atmosphere. Nighttime radiative cooling produces a shallow nocturnal surface inversion layer with a thickness of about 100m, which is much lower than common surface inversion layer, and lifts extremely heated air masses for daytime hours, namely, a warm pool of $34^{\circ}C$ to be isolated over the ground surface in the basin. As heat transfer from the warm pool in the lower atmosphere toward the ground of the basin occurs, the air near the surface of the basin does not much cool down, resulting in the persistence of high temperature at night, called nocturnal thermal high or tropical night. High relative humidity of 75% is found at the surface of the basin under the moderate wind, while slightly low relative humidity of 60% is along the eastern slope of the high mountain, due to adiabatic heating by the srong downslope wind. Air temperature near the surface of the basin with high moisture in the evening does not get lower than that during the day and the high temperature produces nocturnal warming situation.

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하절기 관측을 통한 도시의 지역별 공간녹지분포율에 따른 열환경 특성 연구 (Observational Study of Thermal Characteristics by Distribution Ratio of Green Area at Urban in Summer Season)

  • 정임수;최동호;이부용
    • 한국태양에너지학회 논문집
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    • 제31권3호
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    • pp.8-16
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    • 2011
  • The objective of this study is to analyze the characteristic of thermal environment in the summer season by conducting the field observation of temperature, relative humidity, and globe temperature in some parts of the city. Observation point was divided to a densely populated area, a residential area, a green area, a waterfront green area and a suburban district by the distribution ratio of green area. In this study, the correlation between maximum temperature and globe temperature, study on index for intensity of the tropical night and the temperature distribution characteristic of measurement points by the distribution ratio of green area were analyzed. The results of this study are as follows. (1) The difference between temperature and globe temperature by the distribution ratio of green area is confirmed. The difference of nighttime is more clearly that of daytime. (2) The average temperature and globe temperature of the densely populated area($29.2^{\circ}C$, $33.7^{\circ}C$) are higher than that of the waterfront green area($27.9^{\circ}C$, $32.0^{\circ}C$) by $1.3^{\circ}C$ and $1.7^{\circ}C$, respectively. (3) The number of tropical nights has different days of tropical nights by the distribution ratio of green area of 17days for the Daegu weather station, 14days for adensely populated area, 14days for a residential area, 6days for a green area, 2days for a waterfront green area, and 2days for a suburban district. (4) The results of the slope of trend line for the effects of the temperature on globe temperature change and the intercept for the size of the impact of radiant energy gained around by the analysis of the correlation between the maximum temperature and globe temperature can be utilized objective evaluation index of the each point's artificial effects.