• 대기
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• 제25권2호
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• pp.339-351
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• 2015

The purpose of this study is for the fundamental understandings about building morphological parameters and aerodynamic roughness parameters of Seoul, Korea using the detailed urban geographic information datasets. Applied roughness parameter calculations are based on a digital map of buildings with lot area polygons. The quality of the developed roughness length ($z_0$) of Seoul was evaluated with densely installed 107 automatic weather stations. The correlation coefficient results between averaged wind speeds of AWS data and averaged $z_0$ is -0.303 in night and -0.398 in day (200 m radii circles case). Further $z_0$ enhancement should follow by considering other surface features such as high tree and orography of Seoul. However, this study would meet the needs to for local- or meso-scale meteorological modeling applications of Seoul. However, further studies would require for enhancing the $z_0$ applications of Seoul.

• 한국화재소방학회논문지
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• 제29권5호
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• pp.88-95
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• 2015

본 논문에서는 일상생활에서 화재에 대한 주민들의 경각심을 고취시킬 수 있도록 기상조건에 따른 화재위험을 평가할 수 있는 날씨 관련 서비스를 제안한다. 제안된 서비스는 기상예보에 따른 화재위험평가등급과 특정 기상조건에서 화재요인에 따른 화재위험도를 제공한다. 제안한 서비스에서는 데이터마이닝 기법인 의사결정트리를 이용하여 화재조사데이터와 관측된 기상데이터로부터 화재위험평가등급을 산출할 수 있는 화재 위험도 매트릭스를 생성한다. 주민들은 제안한 서비스를 통해 특정 기상조건에서 화재요인에 따라 화재위험도를 직접 평가할 수 있고, 화재위험도를 저감시킬 수 있는 예방책을 사용자가 선택할 수 있다. 제안한 서비스를 시스템화하여 서비스의 현실성을 확인하였다. 시스템은 온라인상에서 기상청의 기상예보가 갱신될 때마다 시도별로 기상예보에 따른 화재위험평가등급을 표시하고, 각 시도별로 해당 기상조건에서 화재요인에 따라 화재위험도를 평가할 수 있다.

• 대기
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• 제26권1호
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• pp.111-126
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• 2016

In the numerical weather model, surface properties can be defined by various parameters such as terrain height, landuse, surface albedo, soil moisture, surface emissivity, roughness length and so on. And these parameters need to be improved in the Seoul metropolitan area that established high-rise and complex buildings by urbanization at a recent time. The surface roughness length map is developed from digital elevation model (DEM) and it is implemented to the high-resolution numerical weather (WISE-WRF) model. Simulated results from WISE-WRF model are analyzed the relationship between meteorological variables to changes in the surface roughness length. Friction speed and wind speed are improved with various surface roughness in urban, these variables affected to temperature and relative humidity and hence the surface roughness length will affect to the precipitation and Planetary Boundary Layer (PBL) height. When surface variables by the WISE-WRF model are validated with Automatic Weather System (AWS) observations, NEW experiment is able to simulate more accurate than ORG experiment in temperature and wind speed. Especially, wind speed is overestimated over $2.5m\;s^{-1}$ on some AWS stations in Seoul and surrounding area but it improved with positive correlation and Root Mean Square Error (RMSE) below $2.5m\;s^{-1}$ in whole area. There are close relationship between surface roughness length and wind speed, and the change of surface variables lead to the change of location and duration of precipitation. As a result, the accuracy of WISE-WRF model is improved with the new surface roughness length retrieved from DEM, and its surface roughness length is important role in the high-resolution WISE-WRF model. By the way, the result in this study need various validation from retrieved the surface roughness length to numerical weather model simulations with observation data.

• 천문학회보
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• 제38권1호
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• pp.66.1-66.1
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• 2013

Six universities, four institutes and agencies, and two vendors are working for space weather in South Korea. Along with education and research activities, they have been extending ground-based observation system and upgrading space weather service, and participating in international space weather programs. Recently, several space missions for space weather have been proposed in accordance with the national space program of Korea. Here, we report and discuss the current status and future perspective of Korean community for space weather.

• 대기
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• 제27권4호
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• pp.385-398
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• 2017

Numerical weather prediction experiments were carried out by applying topographic effects to reduce or enhance the solar radiation by terrain. In this study, x and ${\kappa}({\phi}_o,\;{\theta}_o)$ are precalculated for topographic effect on high resolution numerical weather prediction (NWP) with 1 km spatial resolution, and meteorological variables are analyzed through the numerical experiments. For the numerical simulations, cases were selected in winter (CASE 1) and summer (CASE 2). In the CASE 2, topographic effect was observed on the southward surface to enhance the solar energy reaching the surface, and enhance surface temperature and temperature at 2 m. Especially, the surface temperature is changed sensitively due to the change of the solar energy on the surface, but the change of the precipitation is difficult to match of topographic effect. As a result of the verification using Korea Meteorological Administration (KMA) Automated Weather System (AWS) data on Seoul metropolitan area, the topographic effect is very weak in the winter case. In the CASE 1, the improvement of accuracy was numerically confirmed by decreasing the bias and RMSE (Root mean square error) of temperature at 2 m, wind speed at 10 m and relative humidity. However, the accuracy of rainfall prediction (Threat score (TS), BIAS, equitable threat score (ETS)) with topographic effect is decreased compared to without topographic effect. It is analyzed that the topographic effect improves the solar radiation on surface and affect the enhancements of surface temperature, 2 meter temperature, wind speed, and PBL height.

• 한국멀티미디어학회논문지
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• 제21권5호
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• pp.599-608
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• 2018

As natural disasters are increasing due to the unusual weather and the modern society is getting complicated, the rapid change of the urban environment has increased human disasters. Thus, citizens are becoming more anxious about social safety. The importance of preparation for safety has been suggested by providing the disaster safety services such as regional safety index, life safety map, and disaster safety portal application. In this paper, we propose an application framework to predict the urban safety index based on user's location with realtime weather/atmosphere data after creating a predication model based on the machine learning using number of occurrence cases and weather/atmosphere history data. Also, we implement an application to provide traffic safety index with executing preprocessing occurrence cases of traffic and weather/atmosphere data. The existing regional safety index, which is displayed on the Si-gun-gu area, has been mainly utilized to establish safety plans for districts vulnerable to national policies on safety. The proposed system has an advantage to service useful information to citizens by providing urban safety index based on location of interests and current position with realtime related data.

• 대기
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• 제20권2호
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• pp.101-109
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• 2010

The service of health information was provided through internal and external weather agency web sites. The purpose of this study was to analyze current status of the weather agency web sites dealing with health information in the internet, and to evaluate their contents and technical aspects. The evaluation tool consisted of five area (appropriateness, accessibility, supportiveness, feedback, and continuance) with nineteen items. For the public confidence, web sites were limited to national meteorological administration and representative weather agencies. The evaluating web sites were fourteen from eight countries. The evaluation scores of fourteen web sites were 37.8 out of 53.0 in total. Each subcategory score were 5-12 out of 12 in appropriate, 4-12 out of 12 in accessibility, 4-10 out of 11 in supportiveness, 2-8 out of 9 in feedback, and 2-8 out of 9 in continuance. The score of feedback was the lowest. Survey results indicated that Korean Meteorological Administration homepage was middle status compared with the others in side of depth of health information and feedback from expert. Climate change affect human health, so it will be possible to prevent some disease at first through climate information. It should be developed to provide high quality health information and system related climate on KMA homepage.

• 산업경영시스템학회지
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• 제41권2호
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• pp.9-15
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• 2018

This study is intended to investigate that it is possible to analyze the public awareness and satisfaction of the weather forecast service provided by the Korea Meteorological Administration (KMA) through social media data as a way to overcome limitations of the questionnaire-based survey in the previous research. Sentiment analysis and association rule mining were used for Twitter data containing opinions about the weather forecast service. As a result of sentiment analysis, the frequency of negative opinions was very high, about 75%, relative to positive opinions because of the nature of public services. The detailed analysis shows that a large portion of users are dissatisfied with precipitation forecast and that it is needed to analyze the two kinds of error types of the precipitation forecast, namely, 'False alarm' and 'Miss' in more detail. Therefore, association rule mining was performed on negative tweets for each of these error types. As a result, it was found that a considerable number of complaints occurred when preventive actions were useless because the forecast predicting rain had a 'False alarm' error. In addition, this study found that people's dissatisfaction increased when they experienced inconveniences due to either unpredictable high winds and heavy rains in summer or severe cold in winter, which were missed by weather forecast. This study suggests that the analysis of social media data can provide detailed information about forecast users' opinion in almost real time, which is impossible through survey or interview.

• 전자통신동향분석
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• 제36권4호
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• pp.48-60
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• 2021

Following the global air-traffic market growth outlook, urgency of technical development is needed in responding to changes in the international air-traffic management paradigm and to prepare technology securing and spreading strategies, which are consistent with systematic aviation weather service policies and evolution direction. Although air traffic has decreased significantly due to COVID-19, normalcy is expected from 2024, as announced by IATA. According to the future air transportation market outlook and development trends of related technologies, Korea has established and implementing the next-generation air transportation system construction plan(NARAE) to secure international competitiveness and leadership in the future. Therefore, this paper describes the technical, economic background and requirements of numerical model-based aviation weather R&D projects for successful implementation of domestic NARAE plans and providing aviation safety and air traffic service efficiency. Furthermore, we proposed numerical-model-based technology development content, strategies and detailed load-map.

• 한국농림기상학회지
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• 제16권4호
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• pp.389-395
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• 2014

이 단보는 농업기상재해 조기경보시스템을 전국적인 현업서비스로 정착시키기 위한 초기단계 기술구현에 관해 설명한다. 먼저 집수역별 기상특보 서비스는 기상청에서 발표하는 기존 150개 시군단위 특보발생 여부를 공간통계기법에 의해 810개 집수역 단위의 순차적인 위험도로 표현하였다. 두번째로 집수역별 지발성 재해경보 서비스는 76개 정규기상관측소의 일별 자료를 토대로 810개 집수역의 중장기 경과기상을 주단위로 감시하여 같은 기간의 기후학적 평년기상에 대비한 현 시점의 만성적 재해위험을 상대지수로 표현하였다. 마지막으로 조기경보서비스 시범지역인 섬진강 하류유역 내 자원농가에 대해여 재해위험을 필지별로 산출하여 개별적으로 전달하기 위한 기반을 마련하였다. 이들 세 종류의 정보를 국토교통부 공간정보 오픈 플랫폼 배경지도 위에 전국 집수역 및 시범지역 내 농장단위 재해위험 레이어로 중첩시켜 준실시간 지도 서비스를 구축하였다.