• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.149-155
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• 2014

The surface solar radiation is an important indicators for climate and agricultural research over the Earth system. For the climate and agricultural research, long-term meteorological data and accurate measured data are needed. The daily solar radiation from Jan. 2001 to Dec. 2010 have been employed in this study analyze atmospheric transmissivity for Chupungryeong. The corresponding daily value of atmospheric transmissivity is calculated for Chupungryeong meteorological data. In this paper, relationship analysis of daily solar radiation and atmospheric transmissivity is presented. It shows that atmospheric transmissivity over late December peaked in the 2000s, substantially decreased from the early-January, and changed little after that in summer. Reduction of solar radiation caused a reduction of more than 0.3 in atmospheric transmissivity during July to August. It was concluded that the atmospheric transmissivity could be very useful for evaluating solar radiation. Atmospheric transmissivity approach is suitable for daily-term simulation studies and useful for computing solar radiation.

• Journal of Institute of Convergence Technology
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• v.4 no.2
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• pp.27-33
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• 2014

To well design the solar energy system using solar energy, the correlation to calculate solar irradiation is basically needed. So, this study was performed to reveal the relationships between the solar irradiation and four meteorological observation data(dry bulb temperature, relative humidity, sunshine duration, and cloud cover) which are different from previous other researches. And then, we finally proposed the first order non-linear correlation from the measured solar irradiation using four meteorological observation data with MINITAB. To show the deviation of the solar irradiation between measured and calculated, this study compared using the daily total solar irradiance and the maximum peak value. From those results, the calculation error was estimated about maximum 25.4% for the daily total solar irradiance. The error of the solar irradiation between measured and calculated was made from the curve fitting error. So, solar irradiation prediction correlation with higher accuracy can be obtained using 2nd or higher order terms with four meteorological observation data.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.638-643
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• 2002

MODIS (MODerate-resolution Imaging Spectroradiometer) onboard the first Earth Observing System (EOS) satellite, Terra, was launched successfully at the end of 1999. The direct broadcast MODIS data has been received and utilized in Korea Meteorological Administration (KMA) since february 2001. This study introduces utilizations of this data, especially for the derivation of sea surface temperature (SST). To produce the MODIS SST operationally, we used a simple cloud mask algorithm and MCSST algorithm. By using a simple cloud mask algorithm and by assumption of NOAA daily SST as a true SST, a new set of MCSST coefficients was derived. And we tried to analyze the current NASA's PFSST and new MCSST algorithms by using the collocated buoy observation data. Although the number of collocated data was limited, both algorithms are highly correlated with the buoy SST, but somewhat bigger bias and RMS difference than we expected. And PFSST uniformly underestimated the SST. Through more analyzing the archived and future-received data, we plan to derive better MCSST coefficients and apply to MODIS data of Aqua that is the second EOS satellite. To use the MODIS standard cloud mask algorithm to get better SST coefficients is going to be prepared.

• Atmosphere
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• v.25 no.2
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• pp.221-233
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• 2015

Pollen is closely related to health issues such as allergenic rhinitis and asthma as well as intensifying atopic syndrome. Information on current and future spatio-temporal distribution of allergenic pollen is needed to address such issues. In this study, the Community Multiscale Air Quality Modeling (CMAQ) was utilized as a base modeling system to forecast pollen dispersal from oak trees. Pollen emission is one of the most important parts in the dispersal modeling system. Areal emission factor was determined from gridded areal fraction of oak trees, which was produced by the analysis of the tree type maps (1:5000) obtained from the Korea Forest Service. Daily total pollen production was estimated by a robust multiple regression model of weather conditions and pollen concentration. Hourly emission factor was determined from wind speed and friction velocity. Hourly pollen emission was then calculated by multiplying areal emission factor, daily total pollen production, and hourly emission factor. Forecast data from the KMA UM LDAPS (Korea Meteorological Administration Unified Model Local Data Assimilation and Prediction System) was utilized as input. For the verification of the model, daily observed pollen concentration from 12 sites in Korea during the pollen season of 2014. Although the model showed a tendency of over-estimation in terms of the seasonal and daily mean concentrations, overall concentration was similar to the observation. Comparison at the hourly output showed distinctive delay of the peak hours by the model at the 'Pocheon' site. It was speculated that the constant release of hourly number of pollen in the modeling framework caused the delay.

• Atmosphere
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• v.25 no.3
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• pp.407-433
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• 2015

First half of my article focused on analyzing the current state of historical materials regarding weather and climate, and established a list of weather-related historical literature collection of Korea with which to make a lexical approach to the situations of all kinds of weather literature. It also put emphasis on gathering information and data of weather logs from journal-type historical records which were contained in 48 weather-related journals of Choseon period. The results of this research are expected to be useful for the activation of study in historical meteorology. The latter half of my research focused on analyzing various meteorological states of sunny, cloudy, rainy, snowy and frosty weather which were recorded in the official Annals of King Kojong (1864~1907). And it re-verified historical rainfall data of preceding researches of Wada Yuji (1917), Jung-Lim (1994), Jhun-Moon (1997). In result, different records were found between data of theirs and mine. It means that we have to analyze and reconstruct newly the meteorological data of the Annals of King Gojong and the Daily Records of Royal Sungjungwon (1623~1910) during the late Choseon period.

• The Korean Journal of Applied Statistics
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• v.25 no.6
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• pp.977-985
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• 2012

Data quality and climate forecasting performance deteriorates because of long climate data contaminated by non-climatic factors such as the station relocation or new instrument replacement. For a trusted climate forecast, it is necessary to implement data quality control and test inhomogeneous data. Before the inhomogeneity test, a reference series was created by $d$ index to measure the temperature series relationship between the candidate and surrounding stations. In this study, a inhomogeneity test to each season and climatological station was performed on the daily mean temperatures, daily minimum temperatures and daily maximum temperatures. After comparing two inhomogeneity tests, the traditional and the adjusted SNHT method, we found the adjusted SNHT method was slightly superior to the traditional one.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.6
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• pp.93-102
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• 2014

Generally data loading is a laborous job to develop models. Meteorological data is basic input data for hydrological models, it is provided through websites of Korea Meteorological Administration (KMA). The website of KMA provides daily meteorological observation data with tabular format classified by years, items, stations. It is cumbersome to manipulate tabular format for model inputs such as time series and multi-item or multi-station data. The provider oriented services which broadcast restricted formed information have caused inconvenient processes. Tim O'Reilly introduces "Web 2.0" which focuses on providing a service based on data. The top ranked IT companies such as google, yahoo, daum, and naver provide customer oriented services with Open API (Application Programming Interface). A RESTful web service, typical implementation for Open API, consists URI request and HTTP response which are simple and light weight protocol than SOAP (Simple Object Access Protocol). The aim of this study is to develop a web-based service that helps loading data for human use instead of machine use. In this study, the developed RESTful web service provides Open API for manipulating meteorological data. The proposed Open API can easily access from spreadsheet programs, web browsers, and various programming environments.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.265-268
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• 2012

There are increasing number of allergic patients due to the increasing outdoor activities and allergenic pollens by local climate changes. Korea Meteorological Administration provides daily forecasts for pollen allergy warnings on the Internet. The forecast models are composed of pollen concentration models and risk grade levels. The accuracy of the models was determined in terms of risk grade. Pollen concentration models were developed using the observed data during from 2001 to 2006 and accuracy was validated against the data during from 2010 to 2011. The accuracy was different from location to location. The accuracy for most tree species was higher in April than that in May. The accuracy for weed species was higher in October than in September. Our result suggest that the models presented in this study can be used to estimate daily number and risk grade of pollens.

• Journal of the Korean Solar Energy Society
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• v.36 no.1
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• pp.1-9
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• 2016

To well design the solar energy system, the correlation to calculate and predict solar irradiation is basically needed. So, this study was performed to reveal the relationships between the solar irradiation and four meteorological observation data(dry-bulb temperature, relative humidity, duration of sunshine, and amount of cloud) that didn't show from previous any other researches. And then, we finally proposed the various order non-linear correlation from the measured solar irradiation and four meteorological measurement data using MINITAB. To show the deviation and accuracy of the solar irradiation between measured and calculated, this study compared for the daily total solar insolation. From those results, the calculation error could well predicted about maximum 97% for the daily total solar insolation. But, the coefficients of the proposed correlations didn't show any relationships. So, needs more studies to make the proper one correlation for the country.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.6
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• pp.87-99
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• 2013

For analysis of climate change effects on agriculture, precise agricultural meteorological data are needed to target period and site. In this study, agricultural meteorological data under new climate change scenario (RCP 8.5) are constructed from 2011 to 2099 in 111 agriculture major station suggested by Rural Development Administration (RDA). For verifying constructed data, comparison with field survey data in Suwon shows same trend in maximum temperature, minimum temperature, average temperature, and precipitation in 2011. Also comparison with normals of daily data in 2025, 2055, and 2085 shows reliability of constructed data. In analysis of constructed data, we can calculate sum of days over temperature and under temperature. Results effectively show the change of average temperature in each region and odd days of precipitation which means flood and dry days in target region.