• Journal of the Korean earth science society
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• v.29 no.5
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• pp.375-385
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• 2008

The relationship between two interannual climate variabilities and the frequency of tropical cyclone (TC) that landed over the Korean Peninsula (KP) has investigated for the period of 1951-2004. In the analysis of the relationship between KP-landfall TC frequency and the ENSO phase, most TCs of C-14 (TCs that do not pass through mainland China before landing the KP) and C-23 (TCs that pass through mainland China before landing the KP) tended to more land in the warm phase than normal and cold phases. However, TC intensity at landfall was stronger in the cold and normal phases. In the analysis of the relationship between KP-landfall TC frequency and Arctic Oscillation (AO) phase, the TCs of C-14 tended to more land in the positive (POS) phase of AO and the negative (NEG) phase of AO for C-23. It was found that AO index was negatively correlated with the Ni$\tilde{n}$o-3.4 index. And then the TCs of C-14 landed more frequently over the KP in the AO POS - Ni$\tilde{n}$o-3.4 NEG phases and in the AO NEG - Ni$\tilde{n}$o-3.4 POS phases for the TCs of C-23.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.10
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• pp.1257-1264
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• 2018

This paper proposes Autoregressive Integrated Moving Average (ARIMA)-based forecasting algorithms using meteorological indices to predict seasonal peak load. First of all, this paper observes a seasonal pattern of the peak load that appears intensively in winter and summer, and generates ARIMA models to predict the peak load of summer and winter. In addition, this paper also proposes hybrid ARIMA-based models (ARIMA-Hybrid) using a discomfort index and a sensible temperature to enhance the conventional ARIMA model. To verify the proposed algorithm, both ARIMA and ARIMA-Hybrid models are developed based on peak load data obtained from 2006 to 2015 and their forecasting results are compared by using the peak load in 2016. The simulation result indicates that the proposed ARIMA-Hybrid models shows the relatively improved performance than the conventional ARIMA model.

• Atmosphere
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• v.19 no.1
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• pp.53-66
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• 2009

The purpose of this study is to describe the roles of carbon dioxide in the climate change, and carbon dioxide reduction policies in some countries. In addition, ways to cope with climate change in Korea are also discussed. Currently, global temperatures are rising due to the carbon dioxide produced by human beings. Global temperatures will rise approximately $6^{\circ}C$ until 2100 if we emit carbon dioxide at a present rate. Temperature rise will affect the terrestrial and oceanic resources, and ultimately influence the socio-economic structures including political stability. Most of the carbon dioxide comes from fossil fuels. Therefore, it is urgent to reduce the use of energy, which comes from fossil fuels. Solving the climate change due to the increases in carbon dioxide is a global problem. Korea should participate in the international community and cooperate with each other in order to reduce the carbon dioxide concentration. No policy was announced for the reduction of carbon dioxide so far. Korea should make a policy for the reduction of carbon dioxide in a specific year compared to that of certain standard year such as 1990 or 2005. Making policy should be based on the scientific result of the amount of carbon dioxide emitted and absorbed. Germanwatch announced the Climate Change Performance Index (CCPI) in order to evaluate an effort to reduce the carbon dioxide for 56 countries which emits 90 % of global carbon dioxide. Ranking for Korea is 51 among 56 countries. This clearly indicates that the appropriate carbon dioxide reduction has not been exercised yet in Korea. Researchers have a moral responsibility to provide updated new ideas and knowledges regarding climate change. Politicians should have a sharp insight to judge the ideas provided by researchers. People need an ethics to reduce the carbon dioxide in every day's life. Scientific research should not be influenced by stress caused by external budget and negative impact of capitalism. Science should be based on the pure curiosity.

• Journal of Environmental Impact Assessment
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• v.16 no.5
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• pp.351-361
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• 2007

To evaluate dominant synoptic classes which affect on $PM_{10}$ concentration in Seoul, 64 synoptic classes are classified from four seasons, 850hPa geopotential wind and lower level stability Index. In this study, we used air monitoring and meteorological data in Seoul for five years from 2001 to 2005. The results indicate that the highest occurrence frequency of synoptic class is under a strong westerly geopotential wind and stable lower atmosphere in spring. The highest $PM_{10}$ concentration of synoptic class is associated with a weak geopotential wind speed and high lower level stability. In that class, not only $PM_{10}$ but $SO_2$, $NO_2$ and CO concentrations are also higher than other classes. The analysis of spacial distribution of $PM_{10}$ concentration in each class are indicate that the influence of synoptic class are similar in the Metropolitan area in Korea. But $PM_{10}$ concentration in some areas in Kyoung-Gi are more higher than in Seoul. The relationship between $PM_{10}$ concentration and Meteorological indicator (relative humidity, temperature, surface wind speed) under same synoptic class is more correlative in Winter than other season.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.4
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• pp.37-48
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• 2018

The extreme 2017 spring drought affected a large portion of central and western South Korea, and was one of the most climatologically driest spring seasons over the 1961-2016 period of record. This drought was characterized by exceptionally low precipitation, with total precipitation from January to June being 50% lower than the mean normal precipitation (1981-2010) over most of western South Korea. In this study, for the quantitative drought impact analysis, the widely-used Standardized Precipitation Index (SPI) and the statistical drought frequency are compared with observed meteorological characteristics and anomalies. According to the drought frequency analysis of monthly cumulative precipitation during January and May in 2017, Gyeonggi-do, Chungcheong-do, and Jeollanam-do areas showed more than drought frequency over 100 years. Gyeongsangnam-do area showed more than drought frequency over 200 years based on annual precipitation in 2017. The South Korean government (Ministry of Agriculture, Food and Rural Affairs (MAFRA) and Korea Rural Community Corporation (KRC)) have been operating a government-level drought monitoring system since 2016. Results from this study can be used to improve the drought monitoring applications of future drought events, as well as drought planning and preparedness in South Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.1
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• pp.30-40
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• 2011

Numerical simulations were carried out to investigate the impact of SST spatial distribution on the result of air quality modeling. Eulerian photochemical dispersion model CAMx (Comprehensive Air quality Model with eXtensions, version 4.50) was applied in this study and meteorological fields were prepared by RAMS (Regional Atmospheric Modeling System). Three different meteorological fields, due to different SST spatial distributions were used for air quality modeling to assess the sensitivity of CAMx modeling to the different meteorological input data. The horizontal distributions of surface ozone concentrations were analyzed and compared. In each case, the simulated ozone concentrations were different due to the discrepancies of horizontal SST distributions. The discrepancies of land-sea breeze velocity caused the difference of daytime and nighttime ozone concentrations. The result of statistic analysis also showed differences for each case. Case NG, which used meteorological fields with high resolution SST data was most successfully estimated correlation coefficient, root mean squared error and index of agreement value for ground level ozone concentration. The prediction accuracy was also improved clearly for case NG. In conclusion, the results suggest that SST spatial distribution plays an important role in the results of air quality modeling on high ozone episode at coastal region.

• Journal of Environmental Science International
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• v.24 no.7
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• pp.893-905
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• 2015

This study analyzes the correlation between Western Pacific (WP) teleconnection pattern index (WPI) in April during 1954-2008 and rainfall amounts in the same month. Based on the results, it is identified that there have been strong positive correlations between central China, Korea and the southwestern part of Japan in the East Asian region. Through differences between 10 positive WP years and 10 negative WP years selected from the April WPI excluding ENSO years, it is found that rainfall amounts increase in April of positive WP years due to the following characteristics. Increases in rainfall amounts are evident in the East Asian middle latitudinal region where the positive correlation between the two variables is the highest and this is because anomalous southwesterlies are strengthened in the East Asian middle latitudinal region due to the spatial pattern of a south-low-north-high anomalous pressure system centered on this region that is made by anomalous anticyclones centered on the southeastern side of the region and other anomalous anticyclones centered on the northeastern side of the region. In addition, anomalous westerlies (jet) are strengthen in the upper troposphere of the East Asian middle latitudinal region and as a result, anomalous upward flows are strengthened in this region and thus anomalous warm air temperatures are formed in the entire level of the troposphere in the region. In addition to atmospheric environments, anomalous warm sea surface temperatures are formed in the seas in the East Asian middle latitudinal region to help the rainfall amount increases in the East Asian middle latitudinal region.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.507-519
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• 2017

The applications of NDVI (Normalized Difference Vegetation Index) as a vegetation index has been widely used to understand vegetation biomass and physiological activities. However, NDVI is not suitable way for monitoring vegetation stress because it is less sensitive to change in physiological state than biomass. PRI (Photochemical Reflectance Index) is well developed to present physiological activities of vegetation, particularly high-light-stress condition, and it has been adopted in several satellites to be launched in the future. Thus, the understanding of PRI performance and the development of analysis method will be necessary. This study aims to interpret the characteristics of light-stress-sensitive PRI in shadow areas and to evaluate the PRI calculated by other wavelengths (i.e., 488.9 nm, 553.6 nm, 646.9 nm, and 668.4 nm) instead of 570 nm that used in original PRI. Using airborne-based hyperspectral image, we found that PRI values were increased in shadow detection due to the reduction of high light induced physiological stress. However, the qualities of both PRI and NDVI data were dramatically decreased when the shadow index (SI) exceeded the threshold (SI<25). In addition, the PRI calculated using by 553.6 nm had best correlation with original PRI. This relationship was improved by multiple regression analysis including reflectances of RED and NIR. These results will be helpful to the understanding of physiological meaning on the application of PRI.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6B
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• pp.541-549
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• 2010

While the number of rainy days is decreasing, the mean annual precipitation is increasing due to abnormal climate changes caused by the global warming in Korea. Owing to the biased-concentration of rainfall during specific short terms, not only flood but also drought becomes more and more serious. From the literature, it is easily found that previous studies about flood have been intensively conducted. However, previous studies about drought have been performed rarely. This study conducted the comparison between two representative drought indexes calculated from soil moisture and precipitation. Study area was Haenam-gun, Jeollanam-do in Korea. Soil Moisture Index(SMI) was calculated from soil moisture data while the Standardized Precipitation Index(SPI) and the Palmer Drought Severity Index(PDSI) were calculated from meteorological data. All monthly data utilized in this study were observed at the KoFlux Tower. After the comparative analysis, three indexes showed similar tendency. Therefore, it is thought that the drought index using soil moisture measured at the KoFlux Tower is reasonable, which is because the soil moisture is immediately affected by all the meteorological factors.

• Journal of the Korean Wood Science and Technology
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• v.46 no.6
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• pp.627-636
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• 2018

This research was performed to supplement the previous research about the driving rain index (DRI) for Korea determined by using daily weather data for 30 years. The average annual driving rain index (AADRI) was calculated from the hourly weather data, and the magnitude of DRI was investigated according to wind directions. The hourly climate data were obtained from the Korea Meteorological Administration (KMA) for the period 2009 to 2017. Of 82 locations investigated, seven were classified into regions where the level of exposure of walls to rain was high. The result showed quite a difference from the previous results, in which no high exposure regions were observed. Since the hourly-based and the daily-based annual driving rain index (ADRI) values showed only a slight difference, the result may be explained by the length of the periods used in both studies. The change of DRI according to wind directions showed that there was a certain range of wind directions in which driving rain easily approached building walls. It suggests that the consideration of wind directions with high DRI would be useful to develop a good design of wooden buildings from the point of wood preservation and maintenance.