• 대한지리학회지
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• 제46권3호
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• pp.257-276
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• 2011

이 연구에서는 극한기온 지수의 변화 경향을 분석하여 도시화 효과가 극한기온의 변화에 미치는 영향을 규명하고자 하였다. 한국에서 60개 기상관측지점을 대상으로 극한기온과 관련된 16개의 지수를 분석하였다. 여름철 관련 극한기온 지수값은 대부분 증가하였고, 겨울철 관련 극한기온 지수값은 감소하였다. 여름철 지수 중 변동 임계치를 갖는 지수가 열대야와 같은 고정 임계치를 갖는 경우보다 증가 경향이 더 뚜렷하였다. 겨울철과 관련된 극한기온 지수값의 감소 경향이 여름철과 관련된 극한기온 지수의 증가 경향보다 뚜렷하였다. 이는 도시의 기온이 여름철보다 겨울철에 더 상승하는 것과 비슷한 결과이다. 일최고기온과 관련된 지수의 증가 경향보다 일최저기온과 관련된 지수의 감소 경향이 뚜렷하다. 이런 결과도 도시에서 최고기온보다 최저기온의 상승 경향이 더 뚜렷한 것과 비슷한 경향이다.

• 한국농림기상학회지
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• 제16권4호
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• pp.297-303
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• 2014

기온감률에 의한 고도보정만으로 표현되지 않는 산악지대의 한낮 기온 분포를 추정하기 위해 사면 일사효과모형이 사용되어왔으나 많은 경우 과다추정 경향이 나타났다. 그 원인을 찾고 기존 방법을 개선하기 위한 방안을 모색하기 위해 야외실험을 수행하였다. 경남 하동군 악양집수역의 고밀도 관측망으로부터 2012~2013년의 맑은 날 1500 기온, 1100-1500 적산일사량, 그리고 평균풍속자료를 수집하여 분석한 결과 고도보정 기온추정오차는 풍속과 높은 상관이 확인되었다. 이 결과를 토대로 일사효과모형을 풍속가중치에 의해 보정하는 간단한 방법을 도출하였다. 이 새로운 방법에 의해 2012-2013 기간 중 맑은 날에 대하여 악양집수역 내 10개 검증관측지점의 1500 기온을 추정하여 실측치와 비교하였다. 또한 기존 고도보정 추정치 및 일사효과모형 추정치와도 비교하였다. 그 결과 고도보정에 의한 추정치의 오차특성인 편기성과, 일사효과모형의 과다추정 경향이 새로운 방법에 의해 크게 개선되는 것을 확인할 수 있었다.

• 한국작물학회지
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• 제48권5호
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• pp.397-401
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• 2003

This experiment was conducted to know the characteristics of kernel growth as affected by various temperature regimes during grain filling using the varieties Hwaseongbyeo, Ilpumbyeo and Chucheongbyeo. The rice plants tested were grown in the natural condition at 1/5000a Wagner pots until flowering. After flowering, the rice plants were moved to controlled temperature conditions in a phytotron. The minimum/maximum daily temperature in the phytotron was controlled by 12/18, 15/21, 18/24, 21/27, and 24/$30^{\circ}C$, respectively. The grain weights were measured every three days after treatment. The mean daily kernel growth rate during active grain filling period showed different responses among varieties under various temperature regimes. The kernel growth rate of Chucheongbyeo was seriously reduced as temperature regimes were decreased. However, that of Ilpumbyeo was not influenced so critically. Ilpumbyeo showed some advantages in grain filling under low temperature regimes compared to Chucheongbyeo. The lag phase in grain filling of Chucheongbyeo was the longest among tested varieties, followed by Hwaseongbyeo under daily mean temperature regime of $15^{\circ}C$. Kernel weight of Ilpumbyeo increased fast in early grain filling phase under low temperature. This characteristic may be favorable for grain filling in temperate zone where the daily mean temperature is drastically dropped during grain filling period. Regression analysis with kernel growth rate and temperature showed the estimated critical low temperature for grain filling among varieties were $9^{\circ}C$, $12^{\circ}C$, $13^{\circ}C$ in Ilpumbyeo, Hwaseongbyeo and Chucheongbyeo, respectively. Under moderate temperature the duration of grain filling of Ilpumbyeo was longer than that of Chucheongbyeo. However, Under low temperature that of Ilpumbyeo was more favorable than Chucheongbyeo.

• Journal of Ecology and Environment
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• 제33권1호
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• pp.37-45
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• 2010

I conducted extensive analyses of daily weather data of precipitation and temperature monitored from the Surface Synoptic Meteorological Station in Seoul from 1 October 1907 to 31 December 2009 to understand how the climate is changing and the ecological implications for Seoul, Korea. Statistical analyses of the data, including the lengths of seasons and growing degree-days (GDD), showed a clear warming trend in the Seoul area over the study period. The mean daily temperature in Seoul increased by $2.40^{\circ}C$ over the period of one hundred years, which was about three times faster than the global trend and it was striking to notice that mean daily temperature in Seoul in recent 30 years was increasing with the rate of $5.50^{\circ}C$ per hundred years, which is an extremely fast rate of increase in temperature. In the last 100 years, an increase in the number of summer days was apparent, coupled with a reduction in the average number of winter days for about 27 to 28 days based on the analysis of mean daily temperature. Although the lengths of spring and autumn have not changed significantly over the century, early initiations of spring and late onsets of autumn were quite apparent. Total annual precipitation significantly increased at the rate of 2.67 mm/year over the last 100 years, a trend not apparent if the analysis is confined to periods of 30 to 40 years. The information has the potential to be used not only for better understanding of ecological processes and hydrology in the area, but also for the sustainable management of ecosystems and environment in the region.

• 한국태양에너지학회 논문집
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• 제29권5호
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• pp.81-87
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• 2009

Computer simulation of buildings and solar energy systems is being used increasingly in energy assessments and design.. Building designers often now predict the performance of buildings simulation programmes that require hourly weather data. However, not all weather stations provide hourly data. Climate prediction models such as HadCM3 also provide the daily average dry bulb temperature as well as the maximum and minimum. Hourly temperature values are available for building thermal simulations that accounts for future changes to climate. In order to make full use of these predicted future weather data in building simulation programmes, algorithms for downscaling daily values to hourly values are required. This paper describes a more accurate method for generating hourly temperature values in the South Korea that uses all three temperature parameters from climate model. All methods were evaluated for accuracy and stability in terms of coefficient of determination and cumulative error. They were compared with hourly data collected in Seoul and Ulsan, South Korea.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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• pp.291-296
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• 2003

This study estimated surface temperature by using split-window technique and NOAA/AVHRR data was used. For surface monitoring, cloud masking procedure was carried out using threshold algorithm. The daily maximum air temperature is estimated by multiple regression method using independent variables such as satellite-derived surface temperature, EDD, and latitude. When the EDD data added, the highest correlation shown. This indicates that EDD data is the necessary element for estimation of the daily maximum air temperature. We derived correlation and experience equation by three approaching method to estimate daily maximum air temperature. 1) non-considering landcover method as season, 2) considering landcover method as season, and 3) just method as landcover. The last approaching method shows the highest correlation. So cross-validation procedure was used in third method for validation of the estimated value. For all landcover type 5, the results using the cross-validation procedure show reasonable agreement with measured values(slope=0.97, intercept=-0.30, R$^2$=0.84, RMSE=4.24$^{\circ}C$). Also, for all landcover type 7, the results using the cross-validation procedure show reasonable agreement with measured values(slope=0.993, Intercept=0.062, R$^2$=0.84, RMSE=4.43$^{\circ}C$).

• 대한지리학회지
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• 제46권2호
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• pp.152-167
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• 2011

이 연구에서는 서울의 1941~1970년(가 기간)과 1971~2000년(나 기간)의 일 평년 기온에 조화분석을 적용하여 계절 추이를 산출, 이의 변화 양상을 살피고, 계절 추이와 변화에 영향을 미치는 요인을 조사하였다. 그 결과 겨울철의 가장 낮은 기온이 가 기간에는 1월초 중순에 나타났으나 나 기간에는 1월 하순~2월 초순에 나타나 계절 추이가 변화되었음을 나타냈다. 이러한 변화는 12월 27일~1월 20일(전기)의 기온이 보다 많이 상승한 반면 1월 21일~2월 9일(후기)의 기온이 보다 적게 상승하였기 때문에 나타났다. 가 기간의 일 평년값에 대한 전기와 후기의 기온 펀치는 1970년 이전에는 큰 차이가 없었으나 1971년 이후에 차이가 컸다. 전기의 경우 시베리아 고기압이 근래에 뚜렷하게 약화되면서 우리나라 부근의 북풍이 약화되어 서울의 기온이 많이 상승하였다. 반면 후기의 경우 시베리아 고기압이 근래에 약화되었으나 알류샨 저기압이 발달하여 우리나라 부근의 북풍은 크게 약화되지 않아 서울 기온이 많이 상승하지 않았다.

• 한국농림기상학회지
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• 제20권3호
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• pp.252-261
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• 2018

이 연구는 월평균 기상자료를 이용하여 일 최고기온, 일 최저기온을 생성하는 방법을 개발하기 위하여 진행되었다. 전국 23개 기상관서의 과거 30년간의 일기상자료를 분석하여 일 최고기온 및 일 최저기온의 연간 변동 경향을 나타내는 모수(중심값($\hat{U}$), 진폭(C), 편이(T))와 일간 변동을 반영하는 모수(A, B)를 탐색하였다. 그 중 중심값은 지점간의 연 평균자료로부터 도출하였고, 중심값을 제외한 모수들은 전국 평균을 기상생성과정에 적용하였다. 먼저 강우발생 유무에 따라 일 기상자료를 생성한 후 월 자료를 이용하여 보정하고 마지막으로 일 최고기온 및 일 최저기온을 생성하였다. 이 방법으로 전체 23개 지역에 대하여 월별로 생성하였을 때 전체 월별 분포의 95% 이상 관측된 분포와 유사한 일 자료를 생성할 수 있었다. 또 이 방법에 의해 과거 자료와 유사한 생장도일(Growing Degree Day)를 생성할 수 있었고, 조사대상이 아닌 지역에도 충분히 적용할 수 있었다. 이 방법은 기후변화시나리오 등 월 자료가 확보되어 있는 경우에 일기상자료를 생성하는데 유용할 것으로 판단되었다.

• 한국태양에너지학회 논문집
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• 제32권2호
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• pp.19-27
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• 2012

This paper describes an experimental study on efficiency of solar collector in solar water heating system connected to hourly water heating load. In general, the functional form of solar efficiency is expressed as a function of fluid temperature entering solar collector, ambient temperature, and solar irradiance. When energy saving from solar heating of water heating system is analyzed on along-term basis such as one year with given solar irradiance data, simplified analysis is more convenient han detailed system simulation for quick assessment. However, the functional form of the efficiency is not convenient for approximately simplified energy analysis because the inlet temperature can be obtained through a detailed system simulation. In the study, solar collector efficiency is obtained with various daily water heating load sand daily solar irradiance using experimental tests. The study also considers large residential buildings such as apartment buildings for application of solar water heating systems. From test results, it is found that daily solar collector efficiency is proportional to daily water heating loads and daily solar irradiance. The data obtained from the study can be utilized to find a functional relation between daily solar irradiance and daily heating load in stead of collector inlet temperature for application of solar collector efficiency to long-term approximated energy analysis of solar heating system.

• Smart Structures and Systems
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• 제19권2호
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• pp.137-149
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• 2017

Under the interference of the temperature effect, the alternation of cable force due to damages of a cable-stayed bridge could be difficult to distinguish. Considering the convenience and applicability in engineering practice, simple air or cable temperature measurements are adopted in the current study for the exclusion of temperature effect from the variation of cable force. Using the data collected from Ai-Lan Bridge located in central Taiwan, this work applies the ensemble empirical mode decomposition to process the time histories of cable force, air temperature, and cable temperature. It is evidently observed that the cable force and both types of temperature can all be categorized as the daily variation, long-term variation, and high-frequency noise in the order of decreasing weight. Moreover, the correlation analysis conducted for the decomposed variations of all these three quantities undoubtedly indicates that the daily and long-term variations with different time shifts have to be distinguished for accurately evaluating the temperature effect on the variation of cable force. Finally, consistent results in reducing the range of cable force variation after the elimination of temperature effect confirm the validity and stability of the developed method.