한반도 동남 지역에서 고농도 오존이 발생한 사례에 대해 NOx에 대한 오존의 수반민감도를 살펴보았다. 사례일에 지배적이었던 국지 순환과 고농도 오존을 모의하기 위해 WRF-CMAQ 모델을 사용하였다. 수반민감도 분석을 위해 CMAQ의 수반 모델을 적용하였다. 본 연구의 목적은 고농도 오존에 주변지역이 미친 영향을 살펴본 수용지 중심의 민감도 분석이다. 또한, 행정 구역별 기여도를 정량적으로 산정하였는데, 대구를 수용지로 하는 민감도 분석 결과 영향지역은 대구에 인접하여 포항으로 이어지는 영역과 남동쪽으로 떨어진 넓은 지역으로 나타났다. 첫 번째 영역은 고농도 사례일 당일에 배출된 NOx의 민감도가 주로 나타났고 두 번째 영역은 전 날 배출에 의한 영향이었다. 반면, 부산을 수용지로 한 경우 사례일 당일 주간의 해풍의 영향으로 같은 날의 NOx 배출 효과 보다는 전 날 배출되었던 농도에 대한 민감도가 더 중요하였다. 민감도 영향지역에 대한 단면도 분석 결과 지표부근의 NOx 수송과 함께 상층에서 이류되는 영향도 중요하였다.

엘니뇨/라니냐의 강도 변화에 따른 한반도의 풍력자원 변동성을 확인하기 위하여 20년간 장기 지상관측자료를 바탕으로 해석적인 분석을 실시하였다. 장기적으로 유라시아 대륙의 풍속 약화경향에도 불구하고 한반도는 최근 10년간 풍속 증가가 약하게 나타났다. 그리고 엘니뇨와 라니냐에 따른 한반도 풍속은 계절적으로 다양한 형태를 나타낸다. 지역적으로 음의 해수면 온도 아노말리를 나타내는 라니냐가 발생하면 한반도내 지상풍속이 빨라지는 경향을 가진다. 그리고 기후변화에 대한 풍속은 중규모의 강제력이 가장 미약한 산악지역에서 가장 민감하게 나타난다.

지표 및 연직기상자료를 이용하여 포항지역 주변의 겨울철 탁월풍 현상을 살펴보고 이 현상을 분석하기 위해 RAMS를 이용한 수치모의를 수행하였다. 조사결과, 상층대기에서는 서풍을 보였으나 지표부근에서는 남서풍이 탁월하였다. RAMS를 이용하여 겨울철 풍계를 살펴본 결과, 이러한 겨울철 탁월풍 현상은 해안선의 형태와 낮은 구릉지, 그리고 바다와 육지의 분포 등의 지형적 특징에 의해 크게 영향을 받는 것으로 분석되었다. 이상의 모형결과의 정확성을 살펴보기 위해 일 중 지속적인 남서풍이 관측되었던 날들의 풍속, 기온, 풍향을 대상으로 관측값과 모형결과값을 비교하였다. 일반적으로 기상관측망은 공간적으로 조밀하지 못하기 때문에 국지순환계의 특징을 자세히 살펴보기가 쉽지 않다. 하지만 이러한 공간적 고분해능을 만족하는 수치모형을 이용한다면 더욱 정확한 결과를 제공받을 수 있을 것이다.

포항일대의 대기환경을 이해하고 예측의 기초정보로 활용하기 위해 기후학적 요소들에 대한 조사를 수행하였다. 분석을 통해, 포항지역의 연평균 기온, 상대습도, 강수량은 각각 14.39˚C, 63.3%, 1,178mm로 나타났다. 포항지역에서의 연간 탁월풍은 남서풍으로 나타났으며 평균풍속은 2.7m/s였다. 운량은 장마기간이 포함되며 지형효과에 의한 대류운이 활발하게 나타나는 여름에 많았다. 또한 연평균 일조시간은 약 2,221시간으로 나타났다.

자동차에서 배출되어지는 NO2(또는 TSP)에 대한 환경영향평가는 사람들의 건강과 환경보존의 관점에서 그 지역의 거주자를 위해서 필요한 것이다. 환경영향평가 수행을 위한 필드 조사에서, 수치모의를 위해서 정확한 농도가 계산되어지고 기상 데이터는 관측되어진다. 수치모의를 하기 위한 배경농도를 결정하기 위해서, NO2(또는 TSP)의 연평균농도는 Puff-Plume 모델을 이용하여 계산되어진다. 만약 계산된 결과들이 환경에 영향을 미치게 되면, 이 결과는 환경보존활동에 고려되어야만 한다. 본 시스템은 이러한 환경영향평가를 예측과정을 손쉽게 할 수 있도록 개발되었다. 또한 이 시스템은 인터체인지와 터널 입구 등과 같은 특수한 도로를 제외한 일반도로에서 배출되는 대기오염의 농도를 예측하고자 하는 사용자를 위하여 제공되어진다. 또한, 이 시스템은 농도의 계산뿐만 아니라 결과를 그래프로 나타내는 기능도 포함되어 있다. 이 시스템을 이용함으로써 직업프로그래머가 아닌 초보자인 사용자일지라도 여러 가지 계산결과 및 결과 그래프를 간단하게 얻을 수 있다.

관측지점의 위치를 살펴보면 해안으로부터 수영은 약 5m정도이고 해운대는 약 1km정도 떨어져 있다. 하지만 해운대에서의 해풍시작시간이 수영보다 빨리 나타난다. 따라서 국지순환모형인 LCM을 이용하여 수영과 해운대에서 해풍시작시간에 대한 지형의 효과를 수치모의 하였다. 이러한 현상은 야간의 복사냉각에 의해 형성된 흐름에 의한 것으로 분석되었는데, 도심지를 둘러싸고 있는 고지대의 경사면을 따라서 수렴된 공기가 가장 저지대인 수영지역으로 흘러가기 때문에 나타난 것으로 이러한 현상은 일출 후에도 나타난다. AWS자료를 분석한 결과, 수영에서 해운대에 비해 약 3배정도 강한 강풍현상이 나타났는데, 이는 수영지역이 야간공기의 유출구이기 때문이다. 이를 통해 지형조건이 해풍의 시작에 중요한 역할을 한다는 것을 알 수 있었다.

본 연구는 강릉 연안지역의 해풍 선정기준과 단 시간 해풍의 기후학적 특성에 관한 것이다. 강릉 연안지역에서의 해풍 선정기준은 다음과 같다. 즉, 육풍에서 해풍으로, 그리고 그 반대로의 분명한 풍향 변화가 있는 가운데 북동 기류와 같이 지형적 원인에 의한 풍향 변화는 해풍 선정에서 제외시켰다. 그리고 해풍이 1시간 또는 2시간만 지속된 경우도 포함시켰다. 이렇게 선정된 해풍 가운데 강릉 연안 지역에서의 가장 큰 특징인 단 시간 해풍에 대한 기후학적 특성을 10년동안(1988년∼1997년)의 자료를 통해 분석하였고 계절별 발생빈도, 발생시간, 풍향, 풍속, 기온으로 구성되었다. 마지막으로 본 연구는 강릉 연안지역 뿐만 아니라 동해안 지역 해풍의 기후학적 특성활용에 대해 간략히 논하였다.

It is well known that atmospheric environments, including both meteorology and air quality, significantly affect public health, such as chronic lung disease and cancer, and respiratory infections. In this study, we have analyzed correlations between the number of daily respiratory outpatients and the atmospheric environments data for about ten years for the city of Busan, South Korea. The respiratory problem patients data have been categorized into two health-vulnerable groups by age over 65(DayPA_O65) and under 20(DayPA_U20), each of which shows relatively higher correlations with air quality and meteorology, respectively. However, time series analysis with factor separation results in that DayPA_O65 and DayPA_U20 show a higher relation with variance components and daily irregular factors of atmospheric concentrations, respectively.

Recently, a variety of modeling studies have been conducted to examine the air quality over South Korea during the Korea United States Air Quality (KORUS-AQ) campaign period (May 1 to June 10, 2016). This study investigates the impact of different meteorological initializations on atmospheric modeling results. We conduct several simulations during the KORUS-AQ period using the Weather Research and Forecasting (WRF) model with two different initial datasets, which is FNL of NCEP and ERA5 of ECMWF. Comparing the raw initial data, ERA5 showed better accuracy in the temperature, wind speed, and mixing ratio fields than those of NCEP-FNL. On the other hand, the results of WRF simulations with ERA5 showed better accuracy in the simulated temperature and mixing ratio than those with FNL, except for wind speed. Comparing the nudging efficiency of temperature and wind speed fields, the grid nudging effect on the FNL simulation was larger than that on the ERA5 simulation, but the results of mixing ratio field was the opposite. Overall, WRF simulation with ERA5 data showed a better performance for temperature and mixing ratio simulations than that with FNL data. For wind speed simulation, however, WRF simulation with FNL data indicated more accurate results compared to that with ERA5 data.

In this study, we investigated the impact of different initial data on atmospheric modeling results using the Weather Research and Forecast (WRF) model. Four WRF simulations were conducted with different initialization in March 2015, which showed the highest monthly mean PM10 concentration in the recent ten years (2006-2015). The results of WRF simulations using NCEP-FNL and ERA-Interim were compared with observed surface temperature and wind speed data, and the difference of grid nudging effect on WRF simulation between the two data were also analyzed. The FNL simulation showed better accuracy in the simulated temperature and wind speed than the Interim simulation, and the difference was clear in the coastal area. The grid nudging effect on the Interim simulation was larger than that of the FNL simulation. Despite of the higher spatial resolution of ERA-Interim data compared to NCEP-FNL data, the Interim simulation showed slightly worse accuracy than those of the FNL simulation. It was due to uncertainties associated with the Sea Surface Temperature (SST) field in the ERA-Interim data. The results from the Interim simulation with different SST data showed significantly improved accuracy than the standard Interim simulation. It means that the SST field in the ERA-Interim data need to be optimized for the better WRF simulation. In conclusion, although the WRF simulation with ERA-Interim data does not show reasonable accuracy compared to those with NCEP-FNL data, it would be able to be Improved by optimizing the SST variable.

The Weather Research and Forecasting (WRF) model and Vegetation Photosynthesis and Respiration Model (VPRM) were coupled to simulate atmospheric CO2 concentrations. The performance of the WRF-VPRM to simulate regional scale CO2 concentration was estimated over coastal basin areas. Either Hestia 2011(HST) or Vulcan 2002(VUL) anthropogenic CO2 emission data were used in two numerical experiments for the study regions. Simulated meteorological variables were validated with ground and background CO2 measurement data, and the results show that the model captured temporal variations of CO2 concentration on a daily basis. CO2 directional analysis revealed that the dominant CO2 emission sources are located S and SW. The simulated Net Ecosystem Exchange (NEE) agreed relatively well with measured CO2 fluxes at each vegetation class site, showing approximately 40% at max improvement at shrub areas.

Since the late 20th century, the urbanization in Korea has been rapidly increasing, especially in major cities like Seoul, as a result of industrialization. One of the aspects of urbanization is coating the surfaces with impervious concrete or asphalt that water cannot penetrate. In addition, various urban, such as urban heat islands, which also have a great impact on the urban environment, occur within the cities. Therefore, the urban environment is gradually becoming hot and dry, and the need for more urban parks to compensate for these negative impacts is growing. Thus, several numerical studies have been conducted to assess these problems using coupled Numerical Weather Prediction (NWP) and Computational Fluid Dynamics (CFD). In this study, an experiment was conducted to determine the accuracy of the area of the input field using Weather Research and Forecasting (WRF) model, and applying the more accurate input field to a numerical simulation using ENVI-met, in order to investigate the effect of urban parks on the thermal comfort. The results showed that an input field with a larger area is more accurate than that with a smaller area, because the surrounding terrain and cities are considered in details in the experiment with the larger area. Subsequently, the more accurate input field was used in ENVI-met, and the results of this simulation showed that the presence of the urban park increased the thermal comfort and improved the humidity conditions.

Wind information is one of the major inputs for the prediction of urban air flow using computational fluid dynamic (CFD) models. Therefore, the numerical characteristics of the wind data formed at their mother domains should be clarified to predict the urban air flow more precisely. In this study, the formation characteristics of the wind data in the Seoul region were used as the inlet wind information for a CFD based simulation and were analyzed using numerical weather prediction models for weather research and forecasting (WRF). Because air flow over the central part of the Korean peninsula is often controlled not only by synoptic scale westerly winds but also by the westerly sea breeze induced from the Yellow Sea, the westerly wind often dominates the entire Seoul region. Although simulations of wind speed and air temperature gave results that were slightly high and low, respectively, their temporal variation patterns agreed well with the observations. In the analysis of the vertical cross section, the variation of wind speed along the western boundary of Seoul is simpler in a large domain with the highest horizontal resolution as compared to a small domain with the same resolution. A strong convergence of the sea breeze due to precise topography leads to the simplification of the wind pattern. The same tendency was shown in the average vertical profiles of the wind speed. The difference in the simulated wind pattern of two different domains is greater during the night than in the daytime because of atmospheric stability and topographically induced mesoscale forcing.

To predict annual energy production (AEP) accurately in the wind farm where located in Seongsan, Jeju Island, Equivalent wind speed (EQ) which can consider vertical wind shear well than Hub height wind speed (HB) is calculated. AEP is produced by CFD model WindSim from National wind resource map. EQ shows a tendency to be underestimated about 2.7% (0.21 m/s) than HB. The difference becomes to be large at nighttime when wind shear is large. EQ can be also affected by atmospheric stability so that is classified by wind shear exponent (). AEP is increased by 11% when atmosphere becomes to be stabilized ( > 0.2) than it is convective ( < 0.1). However, it is found that extreme wind shear ( > 0.3) is hazardous for power generation. This results represent that AEP calculated by EQ can provide improved accuracy to short-term wind power forecast and wind resource assessment.

In order to clarify the characteristics of PM10 in coastal and inland cities and their variation statistical analysis were carried out using environmental and meteorological data observed at Busan and Daegu metropolitans during 4 year from 2010. Averaged PM10 concentration was higher in industrial area than any other land-use sites, and its maximum value reach on over 50 ㎍/㎥ at Jangrim site in Busan. Temporal and spatial variations of PM10 concentration in Busan were more sharply, since topograph and mesoscale wind pattern in Busan is more complicated than those in Daegu. Correlation of PM10 concentrations between sites within Daegu appeared strongly and maximum values R2 is about 0.8. This indicate that because wind pattern induced by mesoscale forcing in Daegu are well unified, the variation of PM10 concentration tends to be similar in all sites within Daegu. However, due to complicate wind pattern induced by topography and coastal line, PM10 correlation of sites within Busan was weaker in comparison with in Daegu. And correlation of PM10 at same lane-use in Busan and Daegu tend to be related to the intensity of meteorological forcing, which can decide the intensity of wind pattern.

In this study the urban atmospheric environment map in Busan was made and it consist of the atmospheric environment element map and the atmospheric environment analysis map. The atmospheric environment element map covered the topography, the urban climate, the air pollutant emission, ozone and PM10 concentrations in Busan and the atmospheric environment analysis map included the thermal environment and the wind flow by using WRF meteorological numerical simulation. The meteorological elements from 2007 to 2011 in Busan were used in this study. As a result, in the center of Busan and Buk-gu along to the Nakdong river was the temperature high. To analyze the air flow of Busan 3 clusters depending on the wind direction were extracted with the cluster analysis. The results of the analysis on the detailed wind field of each cluster showed that the weak ventilation could be happened locally at the specific meteorological condition.

Emissions from aircraft have impacts on the air pollution of airport and the surrounding area. There are methods of emissions calculated as Tier 1, Tier2, Tier 3A and Tier 3B. Thus, this study investigated emissions from aircraft at the Gimhae International Airport using EDMS(Emissions & Dispersion Modeling System) program. Results of estimation from aviation emissions, Tier 3B considering all parts which can occur at the airport has the largest amount emissions. In order to understand the relation between aviation emissions and distribution of ozone concentration over airport area, numerical evaluation were carried out. Although the difference of surface ozone distribution between numerical assessment with and without aviation emissions was little, effects of air pollution at airport area from aviation emissions of NOx and VOCs.

In order to decide the location of appropriate onshore wind farm with higher potential wind energy, several decision processes using Geographic Information System (GIS) including Digital Elevation Map (DEM) were proposed and we also estimated the wind resources through the proposed decision process. Decision process consists with three steps. First step is excluding inappropriate location geographically using DEM data including SRTM (Shuttle Radar Topography Mission) terrain data, landslide, land-use, roadway, and forest road data. And the second step of decision process is consideration of the difficulty caused by the natural environmental problem. This step is carried out using ECVAM (Environmental Conservation Value Assessment Map) data. And final step is determination of the most suitable location through the Moving Suitability Identification Method (MSIM) based on the moving potentially estimated wind resources area. Proposed decision process was applied over the Korean Peninsula. Wind resource potential estimated by the first and the second step is cases shows 35.09 GW and 7.17 GW, respectively, and the total evaluated energy from the all proposed step were 0.43 GW and 1.87 GW for the 3 ㎞and 1.5 ㎞geographical grid size, respectively.

To clarify the characteristics of TKE (Turbulence Kinetic Energy) variation for offshore wind power development, several numerical experiments using WRF were carried out in three different coastal area of the Korean Peninsula. Buoyancy, mechanical and shear production term of the TKE budget are fundamental elements in the production or dissipation of turbulence. Turbulent kinetic energy of the south coast region was higher than in other sea areas due to the higher sea surface temperature and strong wind speed. In south coast region, strong wind passing through the Korea Strait is caused by channelling effect of the terrain of the Geoje Island. Although wind speed is weak in east coast, because of large difference in wind speed between the upper and lower layer, the development of mechanical turbulence tend to be predominant. Since lower sea surface temperature and smaller wind shear were detected in west coastal region, the possibility of turbulence production not so great in comparison with other regions. The understanding of the characteristics of turbulence in three different coastal region can be reduced the uncertainty of offshore wind construction.

To estimate the benefit of high-resolution meteorological data for building energy estimation, a building energy analysis has been conducted over Busan metropolitan areas. The heating and cooling load has been calculated at seven observational sites by using temperature, wind and relative humidity data provided by WRF model combined with the inner building data produced by American Society of Heating Refrigeration and Air-conditioning Engineers (ASHRAE). The building energy shows differences 2-3% in winter and 10-30% in summer depending on locations. This result implicates that high spatiotemporal resolution of meteorological model data is significantly important for building energy analysis.