Relocation of weather station leads to changes in geographical climate factors such as latitude, longitude, elevation, topographical relief and land cover of surrounding area that inf luence on local climate. This study analyzes spatio-temporal characteristics and relationships between geographical factors such as location, topographical relief and land cover, and changes in climate data such as temperature, precipitation and wind due to relocation of 12 weather stations in South Korea. Changes in temperature and moisture are attributed to changes in land cover by the relocation. Wonju and Gumi where the stations were relocated from rural to new built-up area show increases in temperature, while temperature in Sokcho, Changwon, Cheonan, Daejeon, Gunsan and Mokpo decreased with the relocations from urban to rural area. Relative humidity in Mokpo, Gunsan and Daejeon increases due to increase in farming land. Changes in topographical relief influence on precipitation, wind and duration of sunshine. The relocation in Chungju to interior of basin led to decreases in precipitation and duration of sunshine, and Boryeong shows decrease in precipitation by the relocation from windward slope to hilly coastal area. Wind speed in Gunsan with the relocation from coastal to inland area decreased due to influence of neighboring hills. Shadow effect by neighboring building or vegetation can be attributed to changes in duration of sunshine in Gwangju and Wonju.
Sensitivity analysis of the WRF model according to the impact of nudging (e.g., nudging techniques and application domains) was conducted during high nocturnal ozone episode to improve the prediction of the regional ozone concentration in the southeastern coastal area of the Korean peninsula. The analysis was performed by six simulation experiments: (1) without nudging (e.g., CNTL case), (2) with observation nudging (ONE case) to all domains (domain 1∼4), (3) with grid nudging (GNE case) to all domains, (4)∼(6) with grid nudging to domain 1, domain 1∼2 and domain 1∼3, respectively (GNE-1, GNE-2, GNE-3 case). The results for nudging techniques showed that the GNE case was in very good agreement with those observed during all analysis periods (e.g., daytime, nighttime, and total), as compared to the ONE case. In particular, the large effect of grid nudging on the near-surface meteorological factors (temperature, relative humidity, and wind fields) was predicted at the coastline and nearby sea during daytime. The results for application domains showed that the effects of nudging were distinguished between the meteorological factors and between the time periods. When applied grid nudging until subdomain, the improvement effects of temperature and relative humidity had differential tendencies. Temperature was increased for all time, but relative humidity was increased in daytime and was decreased in nighttime. Thus, GNE case showed better result than other cases.
Background : Ginseng is a semi-shade plant which prefers cool temperature and mild lighting, and artificially installed shading facility is required from preventing photo-oxidation occurrence when ginseng is exposed to direct sunlight. High temperature damages are commonly noticed due to recent global warming although more farmers are using aluminum foil and blue light-proof screen instead of 4-layered polyethylene shade net (blue 3 + black 1) to prevent the rise in temperature and influx of rainwater, there are insufficient research conducted. Methods and Results : In mid-March, 2015, we have installed steel A type shading facility after transplanting 2-year-old domestic variety ginseng in 7 lines, 10 rows per 3.3㎡. We have prevented the excessive influx of direct light by fixing 4-layered shade net, aluminum foil and blue light-proof screen as shading materials on facilities and adding 2-layered black polyethylene shade net. During July and August with high temperature, light transmission rates have shown varying according to shading materials used: blue light-proof screen (8.4%) > aluminum foil (5.9%) > 4-layered shade net (3.3%). In case of the highest temperature reached, the order followed blue light-proof screen (42.3℃) > 4-layered shade net (40.8℃) > aluminum foil (38.3℃), and in case of average temperature it followed blue light-proof screen (48.7%) > 4-layered shade net (37.6%) > aluminum foil (33.2%). Although there were no difference about leaf area among the shading materials, ginseng leaf grown in aluminum foil has lower chlorophyll content than the other two treatment plot because of photooxidation by light damage. The 3-yr-old ginseng root weight harvested in end of October increased as follows light-proof screen (14.4g) > 4-layered shade net (11.9g) > aluminum foil (9.8g). Conclusion : Aluminum foil showed greater influx of light but lower temperature than 4-layered shade net due to its materialistic character. However the front side of foil can reflect light and cause photo-oxidation of rear-planted ginseng leaves, so it is a need for improvement. In case of blue light-proof screen, although it had higher inside temperature, the root weight of ginseng was the heaviest because of less influx of light and destruction of chlorophyll.
본 연구에서는 우리나라 강수 및 기온과 다양한 기상인자와의 교차상관관계 분석을 통해 대규모 기후변동이 우리나라에 어떠한 영향을 주는지를 분석하였다. 강수 및 기온자료의 경우 앞선 연구인 “경험적 모드분해법을 이용한 기상인자와 우리나라 강수 및 기온의 상관관계 분석 : I. 자료의 분 해 및 특성분석”의 연구결과를 통해 주기성, 경향성에 따라 분해한 강수 및 기온자료의 내재모드함수를 사용하여, 자료의 변동이 심하고 잡음이 포 함된 원 자료를 통한 상관관계 분석보다 좀 더 명확한 상관계수를 계산하였다. 이렇게 분해된 기상자료와 기상인자간의 교차상관관계 분석을 통해 그 시간차와 상관계수를 계산하여, 주기성과 경향성 측면에서 어떠한 상관관계가 있는지를 분석하였다. 그 결과 주기성 측면에서 엘니뇨현상에 의 한 기후변동이 우리나라 기상현상과 밀접한 관련이 있으며, 경향성 측면에서 기후변화로 인한 해수면 온도 증가추세가 우리나라 기상현상과 밀접 한 연관이 있음을 알 수 있었다.
최근 기후변화로 인한 자연재해가 증가하면서 강수 및 기온자료의 시계열에 대한 변동성과 추세를 분석하여 그 변화를 예측하는 연구의 필요성 이 점점 커지고 있다. 하지만 강수나 기온의 경우 복합적인 요소에 의해 변동이 일어나 자료의 변동성이 매우 심하고 너무 많은 요소를 포함하게 되 어 그 특성을 정확히 판단하기가 쉽지 않다. 따라서 자료의 시계열을 분해하게 되면 각 특성을 가진 요소를 추출할 수 있으므로, 정확한 변동 특성을 파악할 수 있다. 본 연구에서는 우리나라 강수 및 기온자료를 경험적 모드분해법(Empirical Mode Decomposition, EMD)을 통해 주기별로 분해 하여 각각의 내재모드함수(Intrinsic Mode Function, IMF)를 추출하였다. 또한, 추출된 내재모드함수의 에너지 밀도를 이용한 유의성 검정을 통 해 원자료로부터 유의미한 자료를 포함하고 있는 내재모드함수를 선별하고, 이들의 주기성, 경향성을 분석하였다.
We developed the Parameter-elevation Regressions on Independent Slopes Model(PRISM)-based Dynamical downscaling Error correction(PRIDE)-Wind speed(WS) model version 3.0 to produce highresolution( 1km) grid data at a monthly time scale by using observation and Regional Climate Model(RCM) wind speed data. We consequently produced monthly wind speed grid data during the observation period(2000~2014) and the future period(2021~2100) for Representative Concentration Pathway(RCP) 2 type scenarios by using the PRIDE-WS model. The PRIDE-WS model is constructed by combining the MK(Modified Korean)-PRISM-Wind, the RCM anomaly and Cumulative Density Function(CDF) fitting, basically based on Kim et al.(2016)’s algorithm applied for daily precipitation. The upper level wind(80m altitude) was estimated by Deacon equation using surface wind speed that was produced by the PRIDE-WS model. The results show that the wind speed at the upper level generally increased during the summer season while it decreased during the spring, autumn and winter seasons.
The object of this study was to evaluate the effects of climatic elements on potato yield and create a model for estimating the potato yield. We used 35 yield data of Sumi variety produced in mulching cultivation from 17 regions over 11 years. According to the results, some climatic elements showed significant level of correlation coefficient with marketable yield of potato. Totally 22 items of climatic elements appeared to be significant. Especially precipitation for 20 days after planting (Prec_1 & 2), relative humidity during 11~20 days after planting (RH_2), precipitation for 20 days before harvest (Prec_9 & 10), sunshine hours during 50~41 days before harvest (SH_6) and 20 days before harvest (SH_9 & 10), and days of rain during 10 days before harvest (DR_10) were highly significant in quadratic regression analysis. 22 items of predicted yield (Yi=aXi 2 +bXi+c) were induced from the 22 items of climatic elements (step 1). The correlations between the predicted yields and marketable yield were stepwised using SPSS, statistical program, and we selected a model (step 2), in which 4 items of independent variables (Yi) were used. Subsequently the Yi were replaced with the equation in step 1, aXi 2 +bXi+c. Finally we derived the model to predict the marketable yield of potato as below. Y = -336×DR_10 2 + 854×DR_10 – 0.422×Prec_9 2 + 43.3×Prec_9 – 0.0414×RH_2 2 + 46.2×RH_2 – 0.0102×Prec_2 2 – 7.00×Prec_2 – 10039
This study reduced and built Street Canyons created by skyscrapers in order to verify effect of Street Canyons by green wall within the city centre and analysed influence factors on temperature reduction according to applicative types of green wall in the lab. Applicative types were divided into three types such as non- greening type(Case A), one-side greening type(Case B), both side greening type(Case C). The result of analysis of each types showed that average temperature of Case B and Case C is respectively 1.0℃ and 1.7℃ lower than Case A. The result of analysis of WBGT was that the highest temperature was given by Case A(40.2℃) and second one was from Case B(39.8℃) and third one was from (39.1℃) and in UTCI Case A records the highest temperature of 34.7℃ and Case B provided the second highest temperature of 33.9℃ and Case B gave the lowest temperature of 32.7℃. In PMV the highest temperature of 2.65 was from Case B and second one of 2.61 was from Case A and third one of 2.54 was from Case C. Duncan analysis of each types based on solar radiation and thermal comfort generated that there was analytical significance between Case A and Case B and Case B in terms of each types of average temperature reduction. The significance of thermal comfort in WBGT, MRT, PMV showed non-significance but, In UTCI it was analysed that there was significance between Case C and Case A.
Long-term variations of PM10 and the characteristics of local meteorology related to its concentration changes were analyzed at 4 air quality sites (Ido-dong, Yeon-dong, Donghong-dong, and Gosan) in Jeju during two different periods, such as PI (2001-2006) and PII (2007-2013), over a 13-year period. Overall, the long-term trend of PM10 was very slightly downward during the whole study period, while the high PM10 concentrations in PII were observed more frequently than those in PI. The concentration variations of PM10 during the study period was clarified in correlation between PM10 and meteorological variables, e.g. the low (high) PM10 concentration with large (small) precipitation or high (low) radiation and in part high PM10 concentrations (especially, Donghong-dong and Gosan) with strong wind speed and the westerly/northwesterly winds. This was likely to be caused by the transport effect (from the polluted regions of China) rather than the contribution of local emission sources. The PM10 concentrations in “Asian dust” and “Haze” weather types were higher, whereas those in “Precipitation”, “Fog”, and “Thunder and Lighting” weather types were lower. The contribution of long-range transport to the observed PM10 levels in the urban center (Ido-dong, Yeon-dong, and Donghong-dong), if estimated by comparison to the data of the background site (Gosan), was found to explain about 80% (on average) of its input.
초단기 홍수예보를 위한 주요자료로서 최근 기상레이더의 중요성이 크게 부각되고 있다. 기상레이더는 넓은 지역에 걸쳐 실시간으로 강우현상 감시가 가능하며 지상우량계로는 파악이 불가능한 미계측유역을 통과하는 강우장의 이동 및 변화 파악이 가능한 장점이 있다. 본 연구는 강우장의 공간적 분포와 레이더 강우세포를 추적하는 강우장 예측 해석방안을 수립하였다. 이를 위해 강우장의 공간적인 이동을 고려하기 위해 강우장의 바람장 이류(advection) 패턴을 추출하여 각 강우세포가 가지는 이동방향 및 속도를 고려한 강우장 추적기법을 통하여 강우장을 예측하였다. 본 연구를 통하여 개발된 기상레이더 강우장 상관분석 기법을 활용한 초단기강우예측 결과는 집중호우시 홍수 예·경보를 위한 수문모형의 입력자료 로 활용이 가능할 것으로 사료된다.
This study is analysed on corelation between topographical conditions around 36 weather stations and climate data in South Korea. As a result of analysis, the altitude above sea level shows linear negative corelation with temperature. The low relative height sites appear that sunshine duration and temperature are the lowest and precipitation and precipitation duration are bigger than average by influences of surrounding landform. The relief amount shows high positive corelation with precipitation phenomena such as precipitation, precipitation duration and cloud amount. In terms of the aspect, southern slope sites show the highest daily minimum temperature and sunshine duration, and western slope sites show daily mean and maximum temperatures. The eastern close sites appear the lowest temperature and the highest humidity. The distance from coastline shows linear negative corelation with temperature data. The far distance sites from coastline appear that temperature, precipitation and precipitation duration are the lowest. In respect of landform structures, the piedmont areas show the highest moisture related indicators. The hill areas show the lowest humidity and cloud amount and the longest sunshine duration. Temperature and wind speed are low in basin areas.
Comparing to the other air pollutants like SO2, CO, the number of exceedance of the ozone national ambient air quality standard(NAAQS) and the ozone warning increased recently in Busan. The purpose of this study is to find out the preliminary symptoms for high ozone days in Busan area. In order to find out the preliminary symptoms, the hourly ozone data at air quality monitoring stations and the hourly meterological parameters at Busan regional meteorological 2007 to 2013 were used for the analysis. Averaged daily max ozone concentration was the highest(0.055 ppm) at Noksan and Youngsuri in the ozone season from 2007 to 2013. The horizontal distributions of daily max. ozone including all stations in Busan at high ozone days(the day exceeding 0.1 ppm of ozone concentration at least one station) were classified from two to five clusters by hierarchial cluster analysis. The meteorological variables showing strong correlation with daily max. ozone were the daily mean dew point temperature, averaged total insolation, the daily mean relative humidity and the daily mean cloud amount. And the most frequent levels were 19-23℃ in dew point temperature, 21-24 MJ/m2 in total insolation on the day before, 2.6-3.0 MJ/m2 on the very day, 67-80% in relative humidity and 0-3 in cloud amount.
The study investigates the characteristics of PM10 concentration in Guducsan air quality observatory and in particular, analyzes the relationship between sudden increase of PM10 concentration in the morning of spring 2014 and meteorological parameters. PM10 concentration in April was 46.9 ㎍/㎥, the highest, followed by 45.5 ㎍/㎥ and 44.6 ㎍/㎥ in March and May, and 21.9 ㎍/㎥ in August. The low concentration in the early morning appeared on 0800 LST in spring, summer, and fall, whereas it emerged on 0900 LST in winter. High concentration in daytime lasted from 1200 LST to 1500 LST in spring and fall, whereas it continued from 1300 LST to 1600 LST in winter. The findings of PM10 concentration and change of meteorological parameters in Guducsan from April 20th to 27th in 2014 are as follows. The low concentration at dawn and in the morning decreased due to strong land breeze. Also, the sudden increase of PM10 concentration in the morning was attributable to low wind speed. Lastly, the sudden decrease of PM10 concentration in the afternoon was attributed to diffusion by strong sea breeze.
It is the first evaluation model that explains the capabilities of natural disasters and crisis matters by subdividing the evaluation model for organizational management of existing public institutions. This paper improves the capabilities associated with climate change in the future weather systems, including the typhoon and cold weather changes, operational systems, and reflux systems, by carrying out the evaluation of the results. This evaluating model which is response capacity to future climate change, supports the method of Analytic Hierarchy Process and Delphi to calculate the weight of the evaluation model. Using the crisis management of the evaluation model or domestic public institutions, it can be utilized to derive the improvement of capabilities and Risks of typhoon and cold weather.
Visibility and Automatic Weather System(AWS) data near Nakdong river were analyzed to characterize fog formation during 2012-2013. The temperature was lower than its nearby city – Daegu, whereas the humidity was higher than the city. 157 fog events were observed in total during the 2 year period. About 65% of the events occurred in fall (September, October, and November) followed by winter, summer, and spring. 94 early morning fog events of longer than 30 minutes occurred when south westerly wind speed was lower than 2 m/s. During these events, the water temperature was highest followed by soil surface and air temperatures due to the advection of cold and humid air from nearby hill. The observed fog events were categorized using a fog-type classification algorithm, which used surface cooling, wind speed threshold, rate of change of air temperature and dew point temperature. As a result, frontal fog observed 6 times, radiation 4, advection 13, and evaporation 66. The evaporation fog in the study area lasted longer than other reports. It is due to the interactions of cold air drainage flow and warm surface in addition to the evaporation from the water surface. In particular, more than 60% of the evaporation fog events were accompanied with cold air flows over the wet and warm surface. Therefore, it is needed for the identification of the inland fog mechanism to evaluate the impacts of nearby topography and land cover as well as water body.
The seasonal variations of sea surface winds and significant wave heights were investigated using the data observed from the marine meteorological buoys (nine stations) and Automatic Weather Stations (AWSs) in lighthouse (nine stations) around the Korean Peninsula during 2010~2012. In summer, the prevailing sea surface winds over the East/West Sea and the South Sea were northerly/southerly and easterly/westerly winds due to both of southeast monsoon and the shape of Korean Peninsula. On the other hand, the strong northerly winds has been observed at most stations near Korean marginal seas under northwest monsoon in winter. However, the sea surface winds at some stations (e.g. Galmaeyeo, Haesuseo in the West Sea) have different characteristics due to topographic effects such as island or coastal line. The significant wave heights are the highest in winter and the lowest in summer at most stations. In case of some lighthouse AWSs surrounded by islands (e.g. Haesuseo, Seosudo) or close to coast (e.g. Gangan, Jigwido), very low significant wave heights (below 0.5 m) with low correlations between sea surface wind speeds and significant wave heights were observed.
Recent climate change has led to fluctuations in agricultural production, and as a result national food supply has become an important strategic factor in economic policy. As such, in this study, panel data was collected to analyze the effects of seven meteorological elements on the production of five types of grain with error component panel data regression method following the test results of LM tests, Hausman test.
The key factors affecting the production of rice were average temperature, average relative humidity and average ground surface temperature. The fluctuations in the other four grains types are not well explained by meterological elements. For other grains and beans, only average temperature and time (year) affect the production of other grains while average temperature, ground surface temperature, and time (year) influence the production of beans. For barley and millet, only average temperature positively affects the production of barley while ground surface temperature and time (year) negatively influence the production of millet.
The implications of this study are as follow. First, it was confirmed that the meteorological elements have profound effects on the rice production. Second, when compared to existing studies, this study was not limited to rice but encompassed all five types of grains and went beyond other studies that were limited to temperature and rainfall to include various meteorological elements.
Change of weather disaster having occurred in Korea since 1960s was analyzed using newspaper articles recording objective facts and reflecting consciousness of the times. The analysis was carried out on 6 disasters: heavy rainfall, cold wave, heavy snowfall, typhoon, heat wave and drought. To focus on the events having great social impacts, articles were chosen among top articles on the front page and general page of the newspapers. Dong-A Daily News articles were sampled from 1960 to 2013, for 54 years. A total of 315 articles were analyzed, among which typhoon accounted for the largest proportion of 36%. Heavy rainfall, heavy snowfall, drought and cold wave followed typhoon, and the topics of heat wave accounted for the lowest percentage of 6%. Articles of typhoon and heavy rainfall accounted for 57%, which is more than half of all. Drought and cold wave are concentrated in the 60s to 70s, and heavy snowfall and heat wave have sharply increased since 2010, due to the tendency of global warming. Articles have decreased over time because the importance of those articles has declined as a result of social development.
단기간에 발생하는 홍수와 달리 가뭄은 긴 시간 동안 큰 피해를 발생시키기 때문에 가뭄을 효과적인 예측하는 것은 매우 중요하다. 현재까지 제안된 여러 가뭄지수들은 사전에 정의된 등급을 이용하기 때문에 대상자료 자체에 내재된 불확실성을 고려하지 못하고 있다. 본 연구에서는 월 강우량 자료를 이용하여 내재되어 있는 불확실성을 고려할 수 있는 은닉 마코프 모형(Hidden Markov Model, HMM)을 이용하여 기상학적 가뭄을 확률론적으로 평가하였다. 기상청에서 제공하는 1973년부터 2012년까지의 일 강우량 자료와 기후변화정보센터(Climate Change Information Center)에서 제공하는 2013년부터 2100년까지의 기후변화 시나리오(RCP 8.5) 기반 월강우량 자료를 대상으로 총 128년간의 강우량 자료에 HMM에 적용하고 가뭄현상을 분석하였다. 본 연구에서 제안된 은닉 마코프 가뭄지수(Hidden Markov based Drought Index, HMDI)는 자료에 내재된 불확실성을 이용하여 가뭄의 상태를 분류할 수 있으며, 이는 SPI와 같은 기존의 가뭄지수와 달리 특정 시점에서 각 은닉상태들이 나타날 확률로 표현되었다. 또한 HMDI를 이용하여 미래 기상학적 가뭄의 계절·기간별 발생특성과 가뭄위험도를 분석하였다.
영동 지역에서는 해마다 대설로 인한 피해가 발생하고 있다. 최근 2014년 2월에는 총 누적 강설량이 192.8 cm의 기록적인 폭설이 내렸으며, 이로 인해 영동 지역에 크고 작은 재해 피해(약 171억 원) 및 인명 피해(사상자 6명)를 야기했다. 뿐만 아니라 2011년(약 230억 원)과 2013년도(약 75억 원)에도 유사한 대설현상이 발생하여 지역 주민들에게 사회·경제적 손실을 초래하였다. 이에 따라 영동 지역에 재해 피해를 유발하는 대설현상의 특징과 그 피해 규모 및 피해 종류를 분석하여 영동 지역에서 발생하는 재해 피해를 예방하는 기초 자료를 제공하고자 한다.
최근 20년(1993~2012)기간 동안에 영동 지역으로 집중적인 적설량 분포를 보이고, 재해 피해를 입힌 사례는 총 5건이며, 1996년 2월, 1998년 1월, 2005년 3월, 2008년 1월, 그리고 2011년 2월 사례 등이다. 이 사례들에 대해 영동해안지역에 해당하는 강원도, 경상남도, 경상북도, 부산광역시, 그리고 울산광역시의 재해 피해를 분석한 결과, 강원도와 경상북도 지역에서는 모든 사례에서 재해 피해를 입었으며, 재해 피해에 가장 취약한 지역임을 알 수 있다.
이렇게 재해 피해를 일으키는 각 사례의 종관 배경을 살펴보면, 공통적으로 시베리아 고기압의 확장과 남쪽 기압골 또는 저기압의 영향을 받았으며, 1996년, 1998년, 그리고 2005년 사례의 경우, 500 hPa 고도에서의 상층 기압골이 통과하면서 저기압에 동반된 경압불안정과 북쪽 한기이류의 영향으로 북동 계열의 바람이 강화되는 특징이, 2005년과 2011년 사례의 경우에는 부산 및 울진 앞바다 부근에 부저기압이 형성되어 있는 특징이 있었다.