• Journal of Environmental Science International
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• v.16 no.9
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• pp.1051-1061
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• 2007

The impact of midlatitude synoptic system (upper-level trough) on typhoon intensity change was investigated by analyzing the spatial and temporal characteristics of vertical wind shear (VWS), relative eddy momentum flux convergence (REFC), and potential vorticity (PV). These variables were computed over the radial mean $300{\sim}1,000km$ from the typhoon center by using GDAPS (Global Data Assimilation and Prediction System) data provided by the Korea Meteorological Administration (KMA). The selected cases in this study are typhoons Rusa (0215) and Maemi (0314), causing much damage in life and property in Korea. Results show that the threshold value of VWS indicating typhoon intensity change (typhoon to severe tropical storm) is approximately 15 m/s and of REFC ranges 6 to 6.5 $ms^{-1}day^{-1}$ in both cases, respectively. During the period with the intensity of typhoon class, PVs with 3 to 3.5 PVU are present in 360K surface-PV field in the cases. In addition, there is a time-lag of 24 hours between central pressure of typhoon and minimum value of VWS, meaning that the midlatitude upper-level trough interacts with the edge of typhoon with a horizontal distance less than 2,000 km between trough and typhoon. That is, strong midlatitude upper-level divergence above the edge of the typhoon provides a good condition for strengthening the vertical circulation associated with the typhoons. In particular, when the distance between typhoon and midlatitude upper-level trough is less than 1,000 km, the typhoons tend to weaken to STS (Severe Tropical Storm). It might be mentioned that midlatitude synoptic system affects the intensity change of typhoons Rusa (0215) and Maemi (0314) while they moves northward. Thus, these variables are useful for diagnosing the intensity change of typhoon approaching to the Korean peninsula.

• Journal of Environmental Science International
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• v.28 no.4
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• pp.441-454
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• 2019

The present study analyzes the characteristics of 43 typhoons that affected the Korean Peninsula between 2002 and 2015. The analysis was based on 3-second gust measurements, which is the maximum wind speed relevant for typhoon disaster prevention, using a typhoon disaster prevention model. And the distribution and characteristics of the 3-second gusts of four typhoons, RUSA, MAEMI, KOMPASU, and BOLAVEN that caused great damage, were also analyzed. The analysis show that between May and October during which typhoons affected the Korean Peninsula, the month with the highest frequency was August(13 times), followed by July and September with 12 occurrences each. Furthermore, the 3-second gust was strongest at 21.2 m/s in September, followed by 19.6 m/s in August. These results show that the Korean Peninsula was most frequently affected by typhoons in August and September, and the 3-second gusts were also the strongest during these two months. Typhoons MAEMI and KOMPASU showed distribution of strong 3-second gusts in the right area of the typhoon path, whereas typhoons RUSA and BOLAVEN showed strong 3-second gusts over the entire Korean Peninsula. Moreover, 3-second gusts amount of the ratio of 0.7 % in case of RUSA, 0.8 % at MAEMI, 3.3 % at KOMPASU, and 21.8 % at BOLAVEN showed as "very strong", based on the typhoon intensity classification criteria of the Korea Meteorological Administration. Based on the results of this study, a database was built with the frequencies of the monthly typhoons and 3-second gust data for all typhoons that affected the Korean Peninsula, which could be used as the basic data for developing a typhoon disaster prevention system.

• Journal of Environmental Science International
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• v.23 no.3
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• pp.459-472
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• 2014

Storm surge height in the coastal area of Jeju Island was examined using the Princeton Ocean Model(POM) with a sigma coordinate system. Amongst the typhoons that had affected to Jeju Island for six years(1987 to 2003), the eight typhoons(Maemi, Rusa, Prapiroon, Olga, Yanni, Janis, Gladys and Thelma) were found to bring relatively huge damage. The storm surge height of these typhoons simulated in Jeju harbour and Seogwipo harbour corresponded relatively well with the observed value. The occurrence time of the storm surge height was different, but mostly, it was a little later than the observed time. Jeju harbour showed a higher storm surge height than Seogwipo harbour, and the storm surge height didn't exceed 1m in both of Jeju harbour and Seogwipo harbour. Maemi out of the eight typhoons showed the maximum storm surge height(77.97 cm) in Jeju harbour, and Janis showed the lowest storm surge height(5.3 cm) in Seogwipo harbour.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.111-118
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• 2003

Kangwon province has been suffering from the various types of disasters and these disasters stand in the way to sustainable development. The heavy rainfall by typhoon RUSA in 2002 and HAEMI in 2003 damaged to property and bodily injury, and gave us a lesson. Even if the refuge activities plan by local government plan for disaster were established with rainfall event, it could not its role in practice. Beside it, the potential disaster risk remains still in existence because the disaster restoration work aims to original state. Therefore, in this study we focused on the point at issue of disaster countermeasure plan by local government and its integrated plan considering local characteristics.

• Magazine of the Korean Society of Hazard Mitigation
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• v.5 no.4 s.19
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• pp.106-114
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• 2005

• Journal of Environmental Science International
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• v.21 no.4
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• pp.517-533
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• 2012

This study calculated wind speed at the height of 10 m using a disaster prediction model(Florida Public Hurricane Loss Model, FPHLM) that was developed and used in the United States. Using its distributions, a usable information of surface wind was produced for the purpose of disaster prevention when the typhoon attack. The advanced research version of the WRF (Weather Research and Forecasting) was used in this study, and two domains focusing on South Korea were determined through two-way nesting. A horizontal time series and vertical profile analysis were carried out to examine whether the model provided a resonable simulation, and the meteorological factors, including potential temperature, generally showed the similar distribution with observational data. We determined through comparison of observations that data taken at 700 hPa and used as input data to calculate wind speed at the height of 10 m for the actual terrain was suitable for the simulation. Using these results, the wind speed at the height of 10 m for the actual terrain was calculated and its distributions were shown. Thus, a stronger wind occurred in coastal areas compared to inland areas showing that coastal areas are more vulnerable to strong winds.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.64-73
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• 2004

During the period of every summer to early autumn seasons, ships have been wrecked or grounded from effect of a typhoon in the waters around Korean Peninsular. Typhoon Rusa killed more than 100 people in September 2002. Super Typhoon Maemi passed southeast of South Korea in September 12-13, 2003, with gale winds blowing at a record 60 m/s and caused much ship groundings, collisions and sinkings over 3000 in dockyards, harbors and places of refuge. These are things that could have been prevented had there merely been prior warning. The aim of this study is to examine what effect these typhoons had on occurrence characteristics of the maritime accidents in South Korea. In this work, records of marine accidents caused by a typhoon are investigated for the period from 1962 to 2002. The distribution is also compared with the trajectories of typhoons, passed during the 1990-2003. It is shown that attack frequency of typhoon and number of marine accidents is the highest in August. We use the track data of Maemi such as central pressure, maximum sustained wind speed and area of each 15m/s and 25m/s winds as a case study to draw a map as a risk index.

• Journal of Navigation and Port Research
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• v.29 no.2
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• pp.151-157
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• 2005

During the period of every summer to early autumn seasons, ships have been wrecked or grounded from effect of a typhoon in the water areas around Korean Peninsula Typhoon Rusa killed more than 100 people in September 2002. Super Typhoon Maemi passed southeast of South Korea in September 12-13, 2003, with a strong gale blowing at a record 60 m/s and caused much ship groundings, collisions and sinkings over 3000 in dockyards, harbors and places of refuge. These are things that could have been prevented had there merely been prior warning. This study outlines the occurrence characteristics of maritime accidents caused by a typhoon in South Korea for the period from 1962 to 2002. The distribution of the accident records is also compared with the trajectories, winds, central pressures of typhoons, passed during the 1990-2003. It is shown that attack frequency of typhoon and number of marine accidents is the highest in August and the marine accidents due to typhoon have a close relation to the distribution of accumulated wind and pressure fields.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.487-491
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• 2007

Recently, rainfall induced hazard has been increased gradually, for example, typhoon Rusa in 2002 and Maemi in 2003. In addition, localized heavy rainfall has been also caused tremendous damage to railroad systems. Measured data from the Meteorological Adminstration sometimes, However, are not in accordance with those of rain gauges in local area, because of its good distance. This study develop automatic alarming software to estimate and prevent these kind of rainfall induced hazards in railroad system with online transportation.

• Korean Journal of Remote Sensing
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• v.24 no.4
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• pp.359-367
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• 2008

TRMM TMI data were used to investigate a relationship between physical parameters from microwave sensor and typhoon intensities from June to September, 2004. Several data such as 85GHz brightness temperature (TB), polarization corrected temperature (PCT), precipitable water, ice content, rain rate, and latent heat release retrieved from the TMI observation were correlated to the maximum wind speeds in the best-track database by RSMC-Tokyo. Correlation coefficient between TB and typhoon intensity was -0.2 - -0.4 with a maximum value in the 2.5 degree radius circle from the center of tropical cyclone. The value of correlation between in precipitable water, rain, latent heat, and typhoon intensity is in the range of 0.2-0.4. Correlation analysis with respect to storm intensity showed that maximum correlation is observed at 1.0-1.5 degree radius circle from the center of tropical cyclone in the initial stage of tropical cyclone, while maximum correlation is shown in 0.5 degree radius in typhoon stage. Correlation coefficient was used to produce regressed intensities and adopted for typhoon Rusa (2002) and Maemi (2003). Multiple regression with 85GHz TB and precipitable water was found to provide an improved typhoon intensity when taking into account the storm size. The results indicate that it may be possible to use TB and precipitable water from satellite observation as a predictor to estimate the intensity of a tropical cyclone.