• 한국항해항만학회지
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• 제35권1호
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• pp.17-21
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• 2011

이 연구에서는 최근 20년(1989-2008년)간의 우리나라 기상청 자료를 이용하여 우리나라 남해안의 기상재해 특성을 분석하였다. 주요 분석 결과는 다음과 같다. 20년 동안에 남해안에서 발생한 기상재해는 총 149건으로 연평균 7.5건이었다. 7월이 가장 많았고, 그 다음은 8월, 9월의 순이었다. 7-9월의 기상재해가 전체의 약 42%를 차지하였다. 계절로 구분해 보면, 여름에 가장 많았고(전체의 약 39%), 그 다음은 가을, 겨울, 봄의 순이었다. 여름에 기상재해가 가장 많은 것은 주로 태풍과 호우와 같은 기상현상 때문이다. 태풍 중에서도 특히, 남해안에 상륙하는 경우가 대규모의 인적 물적 피해를 입히는 것으로 밝혀졌다. 그와 같은 태풍의 대표적인 예로서는 9112호 글래디스와 0215호 루사 그리고 0314호 매미를 들 수 있다.

• 한국지리정보학회지
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• 제20권3호
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• pp.42-51
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• 2017

대설은 우리나라의 법적 자연재해 중 하나이다. 최근 기상현상에 의한 사회경제적 영향력을 함께 예보하는 영향예보가 부각되고 있으며, 이를 위해서는 먼저 각 지역의 기후적 특징을 분석할 필요가 있다. 본 연구에서는 영향예보의 기반마련을 위해 자기조직화지도를 활용하여 적설동질지역을 구분하여 지역별 적설 특징을 분석했다. 연구결과 적설동질지역은 7개 군집으로 나타났으며, 강설량 및 관측일수, 최대강설량을 이용하여 각 그룹의 특징을 구분했다. 대관령, 강릉시, 정읍시는 강설량이 많은 지역으로, 경상도는 강설량이 적은 지역으로 구분되었다. 선행연구와 비교결과 대표적인 지역이 잘 구분되었으나 강설의 특징은 차이가 있는 것으로 나타났다. 본 연구의 결과는 각 지역의 영향예보를 위한 정책결정에 기초자료로 활용될 수 있다.

• 환경영향평가
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• 제13권4호
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• pp.197-211
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• 2004

Visibility impairment was known as an indicator of the increased air pollution. In many previous studies, it is known that both directly emitted fine particles mainly from vehicles and secondary aerosols from photochemical reactions could contribute to this visibility impairment in addition to the meteorological condition. Furthermore, the visibility showed different change patterns according to the geographical condition. In order to research into the influence of these factors on visibility, this study analyzed the visibility at 15:00, observed from 1990 to 2001 in Seoul, Ganghwa, Susan, Gwangju, Jeju. As a result, the visibility was increased in Seoul except the rainfall period, but in Susan, Gwangju, Jeju, it decreased with the relative humidity (RH). Especially, in Seoul, the number of low visibility days was larger than other sites and variations of the visibility were sensitive to the concentration of air pollutants, such as TSP, $NO_2$, $O_3$. The visibility impairment was mainly observed in meteorological condition of RH<50% and relatively stationary front. Therefore it is inferred that photochemical smog could lead to the low visibility in Seoul. On the other hands, in Ganghwa and Susan, when RH was 60~70%, the low visibility observed under the influence of the transports of air pollutants from nearby cities as well as humid air mass from coastal region. And in Jeju, sea fog and humid air mass caused the visibility impairment when the RH was larger than 80%. Finally, during the observational period, some cases of low visibility phenomena were simultaneously observed in the vast region including Seoul, Susan, Ganghwa. It not only includes the visibility aggravation by Asian Dust, but also could be caused by the movement and diffusion of flying dust or secondary aerosols. Moreover, the result shows that these phenomena could be mainly influenced by meteorological factors covering the wide regions.

• 대기
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• 제30권3호
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• pp.237-248
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• 2020

In order to effectively prepare for damage caused by weather events, it is important to proactively identify the possible impacts of weather phenomena on the domestic society and economy. Text mining and Network analysis are used in this paper to build a database of damage types and levels caused by heat wave. We collect news articles about heat wave from the SBS news website and determine the primary and secondary effects of that through network analysis. In addition to that, based on the frequency with which each impact keyword is mentioned, we estimate how much influence each factor has. As a result, the types of impacts caused by heat wave are efficiently derived. Among these types of impacts, we find that people in South Korea are mainly interested in algae and heat-related illness. Since this technique of analysis can be applied not only to news articles but also to social media contents, such as Twitter and Facebook, it is expected to be used as a useful tool for building weather impact databases.

• 해양환경안전학회지
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• 제7권1호
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• pp.1-6
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• 2001

Recently, EI nino and La nina phenomena have known as a cause of the unusual weather and meterological disasters in the world. The meteorological disasters in Korea have mainly caused by typhoons. In this paper, we studied the relationship between EI Nino and La Nina phenomena and the number of typhoons which have affected on Korea using the long-term data for the period from 1940 to 1999 (60 years) in case of normal years, EI Nino years and La Nina years, the numbers of typhoons which have affected on Korea are 3.1/year, 2.7/year and 3.9/year respectively. The number of typhoons which have affected on Korea in La Nina years is more than those in EI Nino years and normal years The occurrence rate of typhoon in La Nina years is also higher than those in EI Nino years and normal years.

• Journal of Plant Biology
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• 제26권2호
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• pp.101-117
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• 1983

The phenological phenomena in terms of year day index (YDI) in South Korea were studied. The YDI was proposed here, because the remainer index such as Nuttonson's index is unadequate for the interpretation on the phenological phenomena of early spring season in sourthern coastal area. The YDI was calculated by summing daily mean temperature of the year days (YD) above physical zero degree in centigrade, based on the data of the Monthly Weather Reports from 1967 to 1980 by the Central Meteorological Office. The pattern of YDI increase with the increase of YD was similar to that of the remainder index such as the Nuttonson's index. The some YDI distribution maps were made by Yim and Kira (1975), dividing into 30'$\times$40' meshes, in latitude and longtude, on the topographical map(1 : 500,000) of the Korea Peninsula. According to the year day of different localities flowering dates of Prunus yedoensis and other phenological phenomena in various species delayed about 3.5 day as the increase of 1 degree of latitude, which coincides with the Hopkins bioclimatic law. It was found that the YDI is useful to interprete the phenology of plant and animal species and to select the optimum range of cultivars in South Korea.

• 한국환경과학회지
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• 제23권10호
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• pp.1719-1729
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• 2014

This study is carried out in order to bridge the gap to understand the relationships between South Asian and East Asian monsoon systems by comparing the summer (June-September) precipitation of Nepal and South Korea. Summer monsoon precipitation data from Nepal and South Korea during 30 years (1981-2010) are used in this research to investigate the association. NCEP/NCAR reanalysis data are also used to see the nature of large scale phenomena. Statistical applications are used to analyze these data. The analyzed results show that summer monsoon precipitation is higher over Nepal ($1513.98{\pm}159.29mm\;y^{-1}$) than that of South Korea ($907.80{\pm}204.71mm\;y^{-1}$) and the wettest period in both the countries is July. However, the coefficient of variation shows that amplitude of interannual variation of summer monsoon over South Korea (22.55%) is larger in comparison to that of Nepal (10.52%). Summer monsoon precipitation of Nepal is found to be significantly correlated to that of South Korea with a correlation coefficient of 0.52 (99% confidence level). Large-scale circulations are studied to further investigate the relationship between the two countries. wind and specific humidity at 850 hPa show a strong westerly from Arabian Sea to BOB and from BOB, wind moves towards Nepal in a northwestward direction during the positive rainfall years. In case of East Asia, strong northward displacement of wind can be observed from Pacific to South Korea and strong anticyclone over the northwestern Pacific Ocean. However, during the negative rainfall years, in the South Asian region we can find weak westerly from the Arabian Sea to BOB, wind is blowing in a southerly direction from Nepal and Bangladesh to BOB.

• 한국대기환경학회지
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• 제27권6호
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• pp.723-733
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• 2011

The ionic compositions were analyzed from the TSP samples collected at Gosan site in Jeju Island between 2000 and 2008, in order to examine the characteristics of atmospheric aerosols in accordance with the meteorological conditions. For the Asian Dust influence on the ionic compositions, the concentration ratios of $NH_4{^+}$, nss-${SO_4}^{2-}$, $NO_3{^-}$, and $K^+$ were about 1.2~2.3 during Asian Dust over Non-Asian Dust periods, noticeably that of nss-$Ca^{2+}$ was 6.8. Meanwhile the concentrations of nss-${SO_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ have increased as 1.8~4.4 times during the haze event periods, and 1.0~1.6 times during the fog and mist events. The ion balance has resulted that the anionic concentrations are relatively lower than the cationic concentrations, and the discrepancy appears more decidedly as a strong Asian Dust effect. The ammonium ion balance has shown that it exists as a mixture of $NH_4HSO_4$ and $(NH_4)_2SO_4$. The concentration ratios of nss-${SO_4}^{2-}/NO_3{^-}$ for Asian Dust, haze, fog-mist, and non-event periods were respectively 1.8, 5.9, 4.6, and 2.9, which were higher values compared to those in urban areas of China as well as other domestic regions. Especially, the high ratios of sulfur oxides could be presumed by the fact that the longrange transport of air pollutants from Asia continent might affect the atmospheric aerosols of Jeju Island.

• Wind and Structures
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• 제10권3호
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• pp.287-300
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• 2007

Wind action is a factor of fundamental importance in the structural design of light or slender constructions. Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by meteorological phenomena such as Extratropical Storms (EPS) or Tropical Storms. Wind effects due to other phenomena, such as thunderstorms, and its combination with EPS winds in so-called squall lines, are simply neglected. In this paper a model that describes the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS) is proposed. The model is based on a semi empirical representation of an axially-symmetrical flow line pattern that describes a stationary field, modulated by a function that accounts for the evolution of the wind velocity with time. The model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters employed in the model are related to meteorological variables, which are susceptible of statistical assessment. A background wind is also considered, in order to account for the translational velocity of the thunderstorm, normally due to local wind conditions. When the translation of the TS is caused by an EPS, a squall line is produced, causing the highest wind velocities associated with TS events. The resulting vertical velocity profiles were also studied and compared with existing models, such as the profiles proposed by Vicroy, et al. (1992) and Wood and Kwok (1998). The present model predicts horizontal velocity profiles that depend on the distance to the storm center, effect not considered by previous models, although the various proposals are globally compatible. The model can be applied in any region of interest, once the relevant meteorological variables are known, to simulate the excitation due to TS winds in the design of transmission lines, long-span crossings, cable-stayed bridges, towers or similar structures.

• 한국환경과학회지
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• 제22권6호
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• pp.651-666
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• 2013

This study introduces a novel approach to the differentiation of two phenomena, Asian Dust and haze, which are extremely difficult to distinguish based solely on comparisons of PM10 concentration, through use of the Optical Particle Counter (OPC), which simultaneously generates PM10, PM2.5 and PM1.0 concentration. In the case of Asian Dust, PM10 concentration rose to the exclusion of PM2.5 and PM1.0 concentration. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were below 40%, which is consistent with the conclusion that Asian Dust, as a prime example of the coarse-particle phenomenon, only impacts PM10 concentration, not PM2.5 and PM1.0 concentration. In contrast, PM10, PM2.5 and PM1.0 concentration simultaneously increased with haze. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were generally above 70%. In this case, PM1.0 concentration varies because a haze event consists of secondary aerosol in the fine-mode, and the relative ratios of PM10 and PM2.5 concentration remain intact as these values already subsume PM1.0 concentration. The sequential shift of the peaks in PM10, PM2.5 and PM1.0 concentrations also serve to individually track the transport of coarse-mode versus fine-mode aerosols. The distinction in the relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration in an Asian Dust versus a haze event, when collected on a national or global scale using OPC monitoring networks, provides realistic information on outbreaks and transport of Asian Dust and haze.