• 한국환경과학회지
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• 제17권6호
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• pp.657-669
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• 2008

Lately extreme weather event is occurring because of the global warming. Especially disaster due to the extreme heat are increasing but the definition and the standard of the extreme heat is obscure until now. So this study established the extreme heat standard by using the number of daily deaths. As a result, considering the climate of the megalopolis using daily maximum heat index and daily maximum temperature was the best for the standard of the extreme heat. And it showed that extreme heat lasted for 2 days affects the death toll the most. The regional incidence of the extreme heat is highest at August and July, September and June is following.

• 대기
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• 제17권2호
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• pp.185-193
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• 2007

This study investigates urbanization effect in warming trend of surface air temperature over Korea. The data used in this study consist of the daily minimum and maximum temperatures during the period of 32 years(1968-1999) from 16 stations of KMA. To calculate magnitude and trend of urbanization effect, stations were classified into urban and rural stations using population statistics. Urban stations were defined as those with population densities greater than 1000 persons per kilometer squared in 1995. The others were defined as rural stations. The urban stations were also subdivided into two groups according to their population totals. For estimates of urban effect magnitude, temperature change was calculated by comparing 16-year mean values between 1968-83 and 1984-99. Then, the difference between each urban station and every rural station was calculated. During the analysis period of 32 years, maximum temperature increase is $1.22^{\circ}C$. In the total temperature increase, urban effect is estimated by 28.7%. For minimum temperature, it becomes larger by about 10% than that in maximum temperature. Therefore, urban effect in an increasing trend of minimum temperature is 38.9% in the change of $1.13^{\circ}C$.

• 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.

• 한국농림기상학회지
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• 제9권3호
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• pp.195-202
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• 2007

수평면과 경사면간의 일사수광량 편차의 정규화변량인 과열지수는 산악지형에서 일 최고기온 추정오차를 줄이는데 효과가 있다고 알려져 있다. 하지만 계산의 복잡성 때문에 경사도와 경사방향에 근거한 매개변량인 개방지수를 먼저 계산하고 이를 이용하여 과열지수를 간접적으로 추정하는 방법이 널리 쓰이고 있다. 이러한 개방지수 매개 간접추정법이 우리나라와 같이 복잡한 산악지형에서 일 최고기온 추정에 적합한지를 알아보기 위해 강원도 평창군에 위치한 도암댐 표준유역(면적 $149 km^2$, 표고범위 $651{\sim}1,445m$)을 대상으로 야외실험을 실시하였다. 이 지역의 30m 해상도 수치고도모형으로부터 시험유역의 166,050개 격자점의 개방지수와 과열지수를 계산하였다. 이들 간의 관계를 계절별 최적 회귀모형으로 나타내고 이로부터 매월 15일의 과열지수를 개방지수로부터 추정하였다. 인근 대관령기상대와 비슷한 고도(해발 844m)에 경사방향이 서로 다른 7개 지점을 선정하여 온도계를 설치하고 2006년 6월부터 2007년 2월까지의 기온을 10분 간격으로 측정하였다. 추정오차를 종속변수로, 각 지점의 추정 과열지수를 설명변수로 둔 회귀분석을 실시한 결과 결정계수가 겨울 0.46, 가을 0.24, 여름 0.02로서 직접 계산된 과열지수를 설명변수로 하는 경우(겨울 0.52, 가을 0.37, 여름 0.15)에 비해 신뢰도가 떨어진다는 것을 확인하였다.

• 대기
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• 제16권4호
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• pp.269-278
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• 2006

Extremely hot weathers may cause major weather-related deaths in the summertime. Influences of heat waves on daily mortalities in 6 major cities of South Korea were investigated. Daily deaths at Seoul were exponentially increased with the daily maximum temperature. However, there were regional differences of the temperature dependence on the mortality because of an acclimation effect of inhabitants. The threshold temperature (with respect to daily maximum temperature) at Seoul was found to be about $31^{\circ}C$ provided that it is determined by a two-phase regression model. The meteorological causes of recordable hot summer in late July of 1994 and their impacts on human health were also investigated. Strong surface heating caused by strong insolation under conditions with clear sky and dry surface due to prolonged drought was likely to be closely associated with the extreme hot weather in 1994 in South Korea.

• 한국기후변화학회지
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• 제7권2호
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• pp.205-215
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• 2016

The relationship between the climate and the number of heat-related patients in South Korea was analysed in this study. The number of the patients was 1,612 during the summer 2011 to 2015 according to the Heat-related Illness (HRI) surveillance system. The coefficient of determination between the number of the patients and the daily maximum temperature was higher than that between the number of them and the other elements: the daily mean/minimum temperature and relative humidity. The thresholds of daily maximum and minimum temperature in metropolitan cities (MC) were higher than those in regions except for MC (RMC). The higher the maximum and minimum temperature became, the more frequently the heat-related illness rate was observed. The regional difference of this rate was that the rate in RMC was higher than that in MC. Prolonged heat wave and tropical night tended to cause more patients, which continued for 20 days and 31 days of maximum values, respectively. On the other hand, the relative humidity was not proportional to the number of the patients which was rather decreasing at over 70% of relative humidity.

• 대기
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• 제17권2호
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• pp.171-183
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• 2007

Trends of daily maximum and minimum temperatures in major cities of South Korea (Seoul, Busan, Incheon, Daegu, and Ulsan) during the past 40 years (1961-2000) were investigated. Temperature records for the Chupungryeong station were compared with those of the large cities because of the rural environment of the station. There were distinct warming trends at all stations, although the warming rates depend on each station's local climate and environment. The warming rates in Korea are much greater than the global warming trends, by a factor of 3 to 4. The most increasing rate in daily maximum temperature was at Busan with $0.43^{\circ}C$ per decade, the most increasing rate in daily minimum temperature was at Daegu with $0.44^{\circ}C$ per decade. In general, the warming trends of the cities were most pronounced in winter season with an increasing rate of $0.5^{\circ}C$/decade at least. Diurnal temperature range shows positive or negative trends according to the regional climate and environmental change. The frequency distribution of the daily temperatures for the past 40 years at Seoul and Chupungryeong shows that there have been reductions in cold day frequencies at both stations. The results imply that the impacts on human health might be positive in winter and adverse in summer if the regional warming scenario by the current regional climate model reflects future climate change in Korea.

• 한국작물학회지
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• 제42권5호
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• pp.539-547
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• 1997

This study was carried out to identify how soybean seed protein concentration is influenced by climatic factors. Twelve lines selected for seed protein concentration were studied in 13 environments of North Carolina. Sensitivity of seed protein concentration, total seed protein, and seed yield to climatic variables was investigated using a linear regression model. Best response models were determined using two stepwise selection methods, Maximum R-square and Stepwise Selection. There were wide climatic effects in seed protein concentration, total protein and seed yield. The highest protein concentration environment was characterized by the most high temperature days(HTD) and the smallest variance of average daily temperature range (VADTRg), while the lowest protein concentration environment was distinguished by the fewest HTD and the largest VADTRg. For protein concentration, all lines responded positively to average maximum daily temperature(MxDT), HTD, and average daily temperature range(ADTRg) and negatively to ADRa, while they responded positively or negatively to average daily temperature(ADT), variance of average minimum daily temperature (VMnDT), and VADTRg, indicating that genotypes may greatly differ in degrees of sensitivity to each climatic variable. Eleven lines seemed to have best response models with 2 or 3 variables. Exceptionally, NC106 did not show a significant sensitivity to any climatic variable and thus did not have a best response model. This indicates that it may be considered phenotypically more stable. For total seed protein and seed yield, all the lines responded negatively to both ADTRg and VADRa, suggesting that synthesis of seed components may increase with less daily temperature range and less variation in daily rainfall.

• 한국토양비료학회지
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• 제46권5호
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• pp.359-364
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• 2013

This study was conducted to develop a model to estimate crop leaf surface temperature. The results were as following; A definition for the daily time based on elapsed time from the midnight (00:00) as "E&E time" with the unit of Kmin. was suggested. The model to estimate the scaled temperature ($T^*e$) of crop leaf surface temperature by scale factor ($T^*$) according to the "E&E time : Kmin."(X) was developed as eq. (1) $T^*e=0.5{\cdot}sin(X+780)+0.5$ (2) $T^*=(Tx-Tn)/(Tm-Tn)$, Tx : Daily leaf temperature, Tm : Daily maximum leaf temperature, Tn : Daily minimum leaf temperature. Relative sensitivity of the measured temperature compared to the estimated temperature of red pepper, soybean and persimmon was 1.078, 1.033 and 0.973, respectively.

• 한국환경보건학회지
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• 제10권1호
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• pp.1-12
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• 1984

The stochastic characteristics of the daily range of water temperature variation was analyzed by employing the techniques of autocorrelation coefficient, autoreggresive model and crosscorrelation model. These time series included daily observations on maximum and minimum values of water temperature and air temperature. The measurement was made by automatic recording instrument at Gu-yee and Dook-do in Han River, and at Waegwan and Gu-mi in Nackdong River in 1981. As a result of this study, it was found that (1) The correlogram of daily water temperature ranges $\Delta AT_i$ and daily air temperature $\Delta AT_i$ at Gu-mi and Gu-yee showed the exponential curves. (2) The most high frequency values of $\Delta AT_i$ and $\Delta WT_i$ were 11$\circ$C and 0.5${\circ}C$ respectively at every measuring site. (3) The correlation coefficients between the daily mean air temperature AT$_i$ and the daily mean water temperature were fairly high as 0.966 at Dook-do and 0.949 at Gu-yee, but the correlation coefficients between $\Delta AT_i$ and $\Delta WT_i$ were very low as 0.1074 at Gu-yee and 0.0324 at Dook-Do.