• Journal of Environmental Science International
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• v.24 no.11
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• pp.1493-1500
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• 2015

Observation data (1981-2014) and climate change scenario data (historical: 1981-2005; RCP 2.6 and 8.5: 2006-2100) were used to analyze occurrence and future outlook of the extreme heat days and tropical nights in Daegu and Jeju. Then we compared the mortality and observations data (1993-2013). During 1981-2014, the average of extreme heat days (tropical nights) was 24.41 days (12.47 days) in Daegu, and 6.5 days (22.14 days) in Jeju. Extreme heat days and tropical nights have been similarly increased in Daegu, but tropical nights increased more than extreme heat days in Jeju. Extreme heat days and tropical nights in both, Daegu and Jeju showed high correlation with daily mortality, specifically Daegu's correlation was higher than that of jeju. The yearly increasing rate of extreme heat of the future (2076-2100) was 1.7-3.6 times and 7.8-37.7 times higher than the past (1981-2005) in Daegu and Jeju, respectively. The yearly increase rate of tropical nights of future was 2.6-5.0 times and 2.9-5.6 times higher in Daegu and Jeju, respectively. During 2006-2100 periods, the trend of extreme heat days was observed both in Daegu and Jeju. On the average, extreme heat days and tropical nights in Jeju increased more than that of Daegu. However, the trend of extreme heat days increase in Daegu was higher than that in Jeju, whereas, the trend of tropical nights in Jeju was higher than that in Daegu.

• Atmosphere
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• v.19 no.1
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• pp.79-91
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• 2009

Seoul National University General Circulation Model (SNUGCM) has been run for 100 years to obtain daily temperature and meridional velocity at the Northern lower stratosphere. The model results are compared with the NCEP/NCAR reanalysis data. The polar temperature and the eddy heat flux from the model show that the model-produced climatology has well-known cold bias and weaker planetary wave activities. The model climatology also has a lag in the seasonal evolution. The relationship between the model-produced polar temperature and the eddy heat flux is investigated with respect to the interannual and decadal time scales. The interannual variation of the polar temperature is related with both total and stationary eddy heat flux in January and March, which is in agreement with observation. The model, however, does not reproduce the relationship between the decadal variation of the polar temperature and transient eddy heat flux, which is revealed in the observed data.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1179-1186
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• 2012

For better understanding of carbon cycle dynamics of an agro-ecosystem, an accurate assessment of seasonal and daily $CO_2$ flux is essential to understand the relationship between various environmental factors and crop productivity. We developed the automatic sliding canopy chamber (ASCC) system that measured continuous net ecosystem productivity (NEP) over whole growing season under the natural meteorological rhythm. The ASCC was composed of two main parts which were sliding part for measuring NEP, and automatic opening and closing chamber (AOCC) for measuring soil respiration (SR) on the soil surface. The ASCC was developed by using open flow method for measuring soil $CO_2$ efflux. The disturbance of natural meteorological condition was minimized by opening the base frames. In the field test with barley (Hordeum vulgare L.), NEP was calculated at $140mg\;CO_2\;m^{-2}h^{-1}$ on a clear day using continuous data and eliminated the possibility of overestimate about 16% using one hour data during the day time. Unlike other small scale chamber system, installation on cropping-field made it possible to take any modifications which might be caused by natural environmental condition.

• Atmosphere
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• v.26 no.4
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• pp.697-709
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• 2016

This study estimates and evaluates the extreme value of 30 m-resolution daily maximum and minimum temperatures over South Korea, using inverse distance weighting (IDW), parameter-elevation regression on independent slopes model (PRISM) and generalized extreme value (GEV) method. The three experiments are designed and performed to find the optimal estimation strategy to obtain extreme value. First experiment (EXP1) applies GEV firstly to automated surface observing system (ASOS) to estimate extreme value and then applies IDW to produce high-resolution extreme values. Second experiment (EXP2) is same as EXP1, but using PRISM to make the high-resolution extreme value instead of IDW. Third experiment (EXP3) firstly applies PRISM to ASOS to produce the high-resolution temperature field, and then applies GEV method to make high resolution extreme value data. By comparing these 3 experiments with extreme values obtained from observation data, we find that EXP3 shows the best performance to estimate extreme values of maximum and minimum temperatures, followed by EXP1 and EXP2. It is revealed that EXP1 and EXP2 have a limitation to estimate the extreme value at each grid point correctly because the extreme values of these experiments with 30 m-resolution are calculated from only 60 extreme values obtained from ASOS. On the other hand, the extreme value of EXP3 is similar to observation compared to others, since EXP3 produces 30m-resolution daily temperature through PRISM, and then applies GEV to that result at each grid point. This result indicates that the quality of statistically produced high-resolution extreme values which are estimated from observation data is different depending on the combination and procedure order of statistical methods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.11
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• pp.897-906
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• 2002

Standard temperature and absolute humidity weather correlations of Seoul for dynamic energy simulation have been developed regressing the measured data compiled by the Korea Meteorological Adminstration during a 10-year period from 1991 to 2000. The mathematical equations can generate the daily and yearly variations of outdoor weather data with consistency unlike the measured data which may show abnormal behavior, Considering that each hour of the day follows a certain yearly pattern, the correlations are developed for each hour. The derived 24 simple mathematical equations can be used for estimating outdoor temperature and humidity conditions for any arbitrary time of the year.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.4
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• pp.96-110
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• 1989

To suggest the fundamental data for the estimation of crop evaportranspiration by the ca- lculated coefficients for estimating the radiation suitable to the different regions of korea in application of Penman equcation, the daily data such as sc(skycover), n(actual sunshine hours), N(possible sunshine hours), Rs(horizontal solar radiation) and Ra(extraterrestial solar radiation) for 10 years (from 1977 to 1986) collected from 19 meteorological stations were analysed. The results are summarized as follows : 1. The coefficients a, b and c for estimating the radiation taken by the regression method with the daily and monthly mean data of the skycover and the ratio of Rs to Ra were shown as a=0.619, b= -0.0202, c= -0.0023 and a=0.64, b=0.0377 c=0.0001 in ave- rage respectively. 2. The coefficients a and b for estimating the radiation analysed by the regression and arithmetic method from the daily ratio of sunshine hours and Rs to Ra were shown as a= 0.157, b= 0.529, and a=0.119, b= 0.726 in average, respectively. 3. The coefficients a and b for estimating the radiation calculated by the regression me- thod based on the monthly ratio of sunshine hours and radiation were shown as a=0. 319 and b= 0.557 in average. 4. The values of a and b for estimating the radiation taken from the relationship between the daily ratio of sunshine hours and radiation showed high significance level. 5. The standard deviation and the coefficient of variance between the radiation calculated from the coefficients by the regression and arithmetic method with the daily data and the actual radiation were analysed and compared to the results by the coefficients of the modified Penman method (a=0.18, b=0.55) and by those of the F.A.O inodified Penman method(a=0.25, b=0.5). The standard deviation and the coefficient of varia- nce by the regression method in this study showed the lowest value. 6. From the above results, it is suggested that regression method using the coefficients taken from the relationship between the ratio of sunshine hours and the ratio of radia- tion based on the daily data has the highest accuracy in estimating the radiation. 7. The average reference crop evapotranspiration estimating by the modified Penman me- thod using the coefficients a and b derived by the regression method from the daily meterological data was closer to the actual evapotsranspiration of grass measured in Suwon area than the estimated evapotranspiration by the modified Penman method and the F.A.O modified Penman method.

• Journal of the Korean Solar Energy Society
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• v.33 no.6
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• pp.77-84
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• 2013

Degree-day method is very simple but essential index to estimate heating and cooling energy demand in buildings. It has been neglected, however, for the simplicity so it is difficult to find any DB for south Korean cities. Even meteorological department of S. Korea doesn't report the data officially. In this study, current methods that are being used in many countries are investigated and used to calculate degree-days of 35 south Korean cities with 30 years(1981~2010) historical data. The calculation result indicates that the error among 4 major methods are dependent on how daily or hourly temperature are treated in the calculation and how balance point temperature is defined. The errors of the methods are no larger than 6% relative to hourly degree-day method.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.478-490
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• 2017

Objectives: The association of air pollution levels and land-use types with changes in the prevalence of allergic diseases (allergic conjunctivitis, allergic rhinitis, asthma, and atopic dermatitis) was investigated for seven metropolitan cities in Korea Methods: Data on daily hospital visits and admissions (of those under 19 years old) for 2003-2012 were obtained from the National Health Insurance Cooperation. Meteorological data on daily mean temperature, humidity, and air pressure were obtained from the Korea Meteorological Administration. Daily mean or maximum concentration data for five pollutants ($PM_{10}$, $O_3$, $NO_2$, $SO_2$, and CO) as measured at air quality monitoring sites operated by the Ministry of Environment were used. We estimated excess risk and 95% confidence intervals for the increasing interquatile range (IQR) of each air pollutant using Generalized Additive Models (GAM) appropriate for time series analysis. Results: In this study, we observed a significant association between the IQR increases of air pollutants and the prevalence risk of allergic diseases (allergic conjunctivitis, allergic rhinitis, asthma, and atopic dermatitis) in all metropolitan cities after adjusting for temperature, humidity, and air pressure at sea level. Among the air pollutants, $NO_2$ and $PM_{10}$ were associated with the prevalence of asthma, and $O_3$ was associated with only allergic conjunctivitis in regression analysis. However, in GAM analysis considering land-use, $O_3$ and $SO_2$ were associated with allergic conjunctivitis, PM10, O3, NO2, and CO were associated with allergic rhinitis, and $PM_{10}$, $O_3$ and $NO_2$ were associated with asthma in industrial area. Conclusion: This study found a significant association between air pollution and the prevalence of allergic related diseases in industrial areas. More detailed research considering mixed traffic-related air pollution (TRAP) and conducting meta-analyses combining data of the all cities is required.

• Atmosphere
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• v.24 no.4
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• pp.481-489
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• 2014

The Chugugi and Wootaek data of Gyeongsang-do (Dagu, Jinju, Goseong) were restored from "Gaksadeungnok", the governmental documents reported by the local government to the central during the Joseon Dynasty, and analyzed. The duration of the restored data represents 6 years for Daegu (1863, 1872, 1890, 1897, 1898, and 1902), 3 years for Jinju (1897, 1898, and 1900), and 2 years for Goseong (1871 and 1873). Total number of the restored data was 134, including 83 in Daegu, 25 in Jinju, and 26 in Goseong with the period ranging from March to September. The summer data from June to August accounts for approximately 50% (73 data), while the April data also shows relatively high number of 22, followed by September and March. Most data was collected from March to October, while this time winter data was not found even in October. The rainfall patterns using Chugugi data were investigated. First, the number of days with rainfall by annual mean showed 41 days in Daegu, 39 in Jinju, 33 in Goseong, respectively. In terms of the time series distribution of daily rainfall, the ratio between the number of occurrences with over 40 mm of heavy rainfall and the number of rainy days showed 14 times (8%) in Daegu, 24 (39%) in Jinju, and 4 (6%) in Goseong, respectively. The maximum daily rainfall during the period was recorded with 80mm in Jinju on August 24, 1900. The result of analyzing monthly amount of rainfall clearly indicated more precipitation in summer (June, July and August) with the relatively high records of 284 mm and 422 mm in April, 1872 and July, 1902, respectively, in Daegu, while Jinju recorded the highest value of 506 mm in June, 1898. When comparing the data with those observed by Chugugi in Seoul during the same period from "Seungjeongwonilgi", the monthly rainfall patterns in Daegu and Seoul were quite similar except for the year of 1890 and 1897 in which many data were missing. In particular, in June 1898 the rainfall amount of Jinju recorded as much as 506 mm, almost 4 times of that of Seoul (134 mm). Based on this, it is possible to presume that there was a large amount of the precipitation in the southern region during 1898. According to the calculated result of Wootaek data based on Chugugi observations, the unit of 1 'Ri' and 1 'Seo' in Daegu can be interpreted into 18.6 mm and 7.8 mm. When taking into consideration with the previous result found in Gyeonggi-do (Cho et al., 2013), 1 'Ri' and 1 'Seo' may be close to 20.5 mm and 8.1 mm, however, more future investigations and studies will be essential to verify the exact values.

• Korean Journal of Remote Sensing
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• v.34 no.3
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• pp.481-494
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• 2018

The accurate radiative transfer model simulation is essential for an accurate ozone profile retrieval using optimal estimation from backscattered ultraviolet (BUV) measurement. The input parameters of the radiative transfer model are the main factors that determine the model accuracy. In particular, meteorological parameters such as temperature and surface pressure have a direct effect on simulating radiation spectrum as a component for calculating ozone absorption cross section and Rayleigh scattering. Hence, a sensitivity of UV ozone profile retrievals to these parameters has been investigated using radiative transfer model. The surface pressure shows an average error within 100 hPa in the daily / monthly climatological data based on the numerical weather prediction model, and the calculated ozone retrieval error is less than 0.2 DU for each layer. On the other hand, the temperature shows an error of 1-7K depending on the observation station and altitude for the same daily / monthly climatological data, and the calculated ozone retrieval error is about 4 DU for each layer. These results can help to understand the obtained vertical ozone information from satellite. In addition, they are expected to be used effectively in selecting the meteorological input data and establishing the system design direction in the process of applying the algorithm to satellite operation.