• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.169-177
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• 2015

We develop a model to predict typhoons in Korea. We collect data for typhoons and classify those depending on the severity level. Following a Bayesian approach, we develop a model that explains the relationship between different levels of typhoons. Through the analysis of the model, we can predict the rate of typhoons, the probability of approaching Korean peninsular, and the probability of striking Korean peninsular. We show that the uncertainty for the occurrence of various types of typhoons reduces dramatically by adaptively updating model parameters as we acquire data.

• Journal of the Korean Institute of Navigation
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• v.16 no.4
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• pp.47-54
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• 1992

The purpose of this study is to provide against to the meteorological disasters in Korea caused by the typhoons by means of the statistical analyses for the relation between the intensities of the typhoons and the meteorological disasters. The data are extracted from the "TYPHOON REPORT OF KOREA" and the "TYPHOON WHITE BOOK" issued by the Central Meteorological Office. The results are summarized as follows : (1) The annual mean frequency and the total number of the typhoon causing the disasters during 30 years (1956∼1985) are 2.2, 65 respectively, and the highest number appears in August followed by September and the third is July. And the degrees of themeteorolgocal disasters are alsio the same order. (2) The more serious disasters occurred by the TS degree typhoons, and the TS degree typhoons occupy the highest frequency. (3) The more serious disasters occurred by the TS degree typhoons, and the TS degree typhoons occupy the highest frequency. (3) The meteorological disaster per typhoon is most severe in August, and the July and September are alike in the degree of the disasters per typhoon. (4) The meteorological disasters are approximately a proportional relation to the intensities of the typhoons. (5) The frequency of the Rain typhoon , Wind typhoon and Rain·Wind typhoon are about 2 : 1: 3 in July, August and September respectively. And the severe disasters occur more frequently by the Rain typhoon than by the Wind typhoon.

• Water for future
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• v.17 no.4
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• pp.273-279
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• 1984

An attempt is made to present a method of prediction for typhoons apporaching the Korean-peninsula. The method is based upon the Bayesian theorem to improve the observed (prior) probabilities of typhoons approaching the Korean sea area incorporating conditional probability. A total of 248 typhoons is collected and analyzed to establish prior probability and conditional probability according to the defined procedure. The typhoons used are those which encompassed the western Pacific area to which the Korean-peninsula is subjected. The results of examplary computations suggest that the presented method is promising for predicting approaching typhoons.

• 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.

• Water for future
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• v.16 no.4
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• pp.253-257
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• 1983

In an attempt to study the frequency and characteristics of typhoons which hit the Korean Peninsula a period of 40 years from 1946 through 1979 was covered to collect necessary data with respect to occurrence of typhoons and their influence Typhoons which occurred between 1959 and 1980 were grouped according to their treking routes and strengths for detailed analyses. The results are summarized as follow; 1. The average annual occurrence of typhoons in the western pacific ocean was found to be 28, only two of which attacked the Korean Peninsula. 2. The annual probabilities of typhoons attacking were 0.925 for one or more, 0.700 for twice or more and 0.323 for there times or moro. 3. The monthly probabilities were found to be 0.228 in July, 0.434 in August and 0.194 in September. 4. An half of the typhoons which hit the Korean Pennisula passed through the western coast and the rest through the southern and eastern coasts in similan proportions. 5. The western coast is hit most frequently in July and less afterwords, visa-vis the southern and the eastern coast. 6. The minimum SLP averaged 983 mb and ordered by the treking routes as S

• Structural Monitoring and Maintenance
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• v.1 no.1
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• pp.47-67
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• 2014

This study has been motivated to examine the performance of a wireless sensor system under the typhoons as well as to analyze the effect of the typhoons on the bridge's vibration responses and the variation of cable forces. During the long-term field experiment on a real cable-stayed bridge in years 2011-2012, the bridge had experienced two consecutive typhoons, Bolaven and Tembin, and the wireless sensor system had recorded data of wind speeds and vibration responses from a few survived sensor nodes. In this paper, the wireless structural health monitoring of stay cables under the two consecutive typhoons is presented. Firstly, the wireless monitoring system for cable-stayed bridge is described. Multi-scale vibration sensor nodes are utilized to measure both acceleration and PZT dynamic strain from stay cables. Also, cable forces are estimated by a tension force monitoring software based on vibration properties. Secondly, the cable-stayed bridge with the wireless monitoring system is described and its wireless monitoring capacities for deck and cables are evaluated. Finally, the structural health monitoring of stay cables under the attack of the two typhoons is described. Wind-induced deck vibration, cable vibration and cable force variation are examined based on the field measurements in the cable-stayed bridge under the two consecutive typhoons.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.109-112
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• 2008

The purpose of this study is to find out the characteristics of disasters caused by typhoons passing through the sea area around the Korean Peninsula. It analyzed two cases, that is, in WEST and EAST cases. These include the typhoons passing through the Yellow Sea, west of the Peninsula and East Sea, east of the Peninsula without landing on the Peninsula. FCM (Fuzzy Clustering Method) analysis was performed on typhoons affecting the Korean Peninsula from 1951 to 2006. The analysis shows that WEST case's cluster has the curved track of NE-S, and EAST case's cluster has the straight track of NE-SW. Typhoons that pass through the Yellow Sea have little change in frequency and the weak intensity. On the other hand, the frequency and the intensity of typhoons passing through the East Sea show the increasing trend. The characteristic of disasters by typhoons affecting the Korean Peninsula from 1973 to 2006 appears differently for each case: EAST cases caused significant damage in flooding, while WEST cases did damage in houses, ships, roads, and bridges. Rainfall amount and maximum wind speed data are analyzed in order to understand the impact of the typhoons, and the result indicates that the WEST cases are influenced by the wind, and East cases by precipitation. The result of this study indicates that the characteristic of disasters is distinctive according to the Typhoon's track. If applied to establish the disaster prevention plan, this result could make a contribution to the damage reduction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.1
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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.

• Proceedings of the KSRS Conference
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• v.2
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• pp.918-921
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• 2006

The short-term variation of sea surface temperature before and after typhoons and increase of chlorophyll a concentration that accompany with the typhoons during summer in the East/Japan Sea were explored by satellite. Four typhoons (NAMTHEUN, MEGI, CHABA and SONGDA) and a typhoon (NABI) passed over the East/Japan Sea in 2004 and 2005, respectively. Decreasing of SST was observed in the every five typhoons, however the magnitude of SST decreasing were various from 1 to $5^{\circ}C$. Chlorophyll a increases were found after the typhoons (0.1-3 ${\mu}g$ $l^{-1})$ except NAMTHEUN, and the area was approximately included in SST decreasing area by the typhoons. It suggests that chlorophyll a increase was caused by nutrient input from subsurface layer by strong mixing. On the other hand, rarely chlorophyll a increase was observed in northern area of polar frontal zone, which is located in $38-41^{\circ}N$, than northern area, and chlorophyll a increase in coastal area was higher (more than 3 times) than offshore area. It might suggest that chlorophyll a increase in the East/Japan Sea is also related with the depth or nitracline depth that affects the amount of nutrients supply to the upper layer by typhoon mixing.

• Journal of the Korean association of regional geographers
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• v.19 no.3
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• pp.384-400
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• 2013

In this study, spatio-temporal patterns of extreme precipitation events caused by typhoons are examined based on observational daily precipitation data at approximately 340 weather stations of Korea Meterological Administration's ASOS (Automated Synoptic Observation System) and AWS (Automatic Weather System) networks for the recent 10 year period (2002~2011). Generally, extreme precipitation events by typhoons exceeding 80mm of daily precipitation commonly appear in Jeju Island, Gyeongsangnam-do, and the eastern coastal regions of the Korean Peninsula. However, the frequency, intensity and spatial extent of typhoon-driven extreme precipitation events can be modified depending on the topography of major mountain ridges as well as the pathway of and proximity to typhoons accompanying the anti-clockwise circulation of low-level moisture with hundreds of kilometers of radius. Yellow Sea-passing type of typhoons in July cause more frequent extreme precipitation events in the northern region of Gyeonggi-do, while East Sea-passing type or southern-region-landfall type of typhoons in August-early September do in the interior regions of Gyeongsangnam-do. These results suggest that when local governments develop optimal mitigation strategies against potential damages by typhoons, the pathway of and proximity to typhoons are key factors.