명량해전 당일 울돌목 조류.조석 재현을 통한 해전 전개 재해석

변도성,이민웅,이호정,Byun, Do-Seong,Lee, Min-Woong,Lee, Ho-Jung 한국군사과학기술학회 2011 한국군사과학기술학회지 Vol.14 No.2

As a multidisciplinary study encompassing oceanography and history, we have attempted to reanalyze the course of a historical navel battle, Myungryang Naval Battle(September 16th, 1597 according to the lunar calendar) through hindcasting the paleo-tidal currents and -tides(PTC). Firstly, we conducted harmonic analysis using 6-month current data observed at Uldolmok and 1-year elevation data provided by Korea Ocean Research and Development Institute in order to understand their characteristics and to hindcast the PTC. Observation results show that Uldolmok, ~300m wide, relatively narrow channel, is characterized by a flood-dominant mixed mainly semidiurnal tidal regime induced by relatively-strong shallow water constituents, showing closely a standing wave type of tidal current. Further, we hindcasted PTC on the day of Myungryang Naval Battle. Our results were compared and discussed with results(time and speeds of maximum(flood and ebb) currents and high and low water times) of the previous studies estimated from different methods. Lastly, we reconstruct the course of the event of Myungryang Naval Battle recorded in the Admiral Sun-Sin Yi's War Diary(Nangjung Iigi in Korean) based on our hindcasting results.

Estimation of the PAR Irradiance Ratio and Its Variability under Clear-sky Conditions at Ieodo in the East China Sea

변도성,조양기 한국해양과학기술원 2006 Ocean science journal Vol.41 No.4

Determining photosynthetically active radiation (PAR) is a key part of calculating phytoplankton productivity in a biogeochemical model. We explore the daily and seasonal variability in the ratio of PAR irradiance to total irradiance that occurred at Ieodo Ocean Research Station (IORS) in the East China Sea under clear-sky conditions in 2004 using a simple radiative transfer model (RTM). Meteorological data observed at IORS and aerosol optical properties derived from Aerosol Robotic Network observations at Gosan are used for the RTM.Preliminary results suggest that the use of simple PAR irradiance-ratio values is appropriate in calculating phytoplankton productivity as follows: an average of 0.44 (0.01) in January to an average of 0.48 (0.01) in July, with average daily variabilities over these periods of about 0.016 (0.008) and 0.025 (0.008), respectively. The model experiments demonstrate that variations in the major controlling input parameters (i.e. solar zenith angle, precipitable water vapor and aerosol optical thickness) cause PAR irradiance ratio variation at daily and seasonal timescales. Further, increases (>0.012) in the PAR irradiance ratio just below the sea-surface are positively correlated with high solar zenith angles and strong wind stresses relative to those just above the sea-surface.

인천항 협수로에서 S2와 K1 조류분조 조화상수의 월변동성 완화

변도성,조창우,이은일,임세한 대한조선학회 2011 대한조선학회 학술대회자료집 Vol.2011 No.6

인공위성 고도계로 관측한 계절별 인도양 표층해류 순환 특성

변도성,황진아,박세영,이주영,이은일 한국해양환경·에너지학회 2012 한국해양환경·에너지학회 학술대회논문집 Vol.2012 No.5

인공위성 고도계로 관측한 계절별 인도양 표층해류 순환 특성

변도성,황진아,박세영,이주영,이은일 대한조선학회 2012 대한조선학회 학술대회자료집 Vol.2012 No.5

한국 연안에서 1999년부터 2017년까지 해수물성과 대기압 변화에 따른 계절 비천문조와 월평균 해수면 변화

변도성,최병주,김효원 한국해양학회 2021 바다 Vol.26 No.1

The solar annual (Sa) and semiannual (Ssa) tides account for much of the non-uniform annual and seasonal variability observed in sea levels. These non-equilibrium tides depend on atmospheric variations, forced by changes in the Sun's distance and declination, as well as on hydrographic conditions. Here we employ tidal harmonic analyses to calculate Sa and Ssa harmonic constants for 21 Korean coastal tidal stations (TS), operated by the Korea Hydrographic and Oceanographic Agency. We used 19 year-long (1999 to 2017) 1 hr-interval sea level records from each site, and used two conventional harmonic analysis (HA) programs (Task2K and UTide). The stability of Sa harmonic constants was estimated with respect to starting date and record length of the data, and we examined the spatial distribution of the calculated Sa and Ssa harmonic constants. HA was performed on Incheon TS (ITS) records using 369-day subsets; the first start date was January 1, 1999, the subsequent data subset starting 24 hours later, and so on up until the final start date was December 27, 2017. Variations in the Sa constants produced by the two HA packages had similar magnitudes and start date sensitivity. Results from the two HA packages had a large difference in phase lag (about 78°) but relatively small amplitude (<1 cm) difference. The phase lag difference occurred in large part since Task2K excludes the perihelion astronomical variable. Sensitivity of the ITS Sa constants to data record length (i.e., 1, 2, 3, 5, 9, and 19 years) was also tested to determine the data length needed to yield stable Sa results. HA results revealed that 5 to 9 year sea level records could estimate Sa harmonic constants with relatively small error, while the best results are produced using 19 year-long records. As noted earlier, Sa amplitudes vary with regional hydrographic and atmospheric conditions. Sa amplitudes at the twenty one TS ranged from 15.0 to 18.6 cm, 10.7 to 17.5 cm, and 10.5 to 13.0 cm, along the west coast, south coast including Jejudo, and east coast including Ulleungdo, respectively. Except at Ulleungdo, it was found that the Ssa constituent contributes to produce asymmetric seasonal sea level variation and it delays (hastens) the highest (lowest) sea levels. Comparisons between monthly mean, air-pressure adjusted, and steric sea level variations revealed that year-to-year and asymmetric seasonal variations in sea levels were largely produced by steric sea level variation and inverted barometer effect. 비천문조인 연주조(Sa)와 반년주조(Ssa)는 해수특성 변화와 기상 상태에 영향을 받는 비대칭 월평균 해수면의 연변화와 관련이 깊다. 국립해양조사원이 운영하는 21개 조위관측소에서 관측한 1시간 간격의 19년(1999~2017년) 간 해수면 높이 자료에 대하여 두 종류의 조석 조화분해 프로그램(Task2K와 UTide)을 사용하여 Sa와 Ssa의 조화상수를 산출하였다. 조화분해에 사용되는 자료의 시작 시기와 길이에 따른 Sa의 안정도를 조사하였으며, Sa와 Ssa의 조화상수의 분포 특성을 살펴보았다. 먼저, 인천 조위관측소의 20년(1999~2018년) 해수면 관측자료를 1일씩 이동하면서 1년(369일) 조화분해를 수행하고 그 결과를 비교하였을 때, 두 프로그램 모두 자료의 시작 시기에 따라 Sa 조화상수가 불규칙하게 크게 변동한다는 사실을 알 수 있었다. Task2K가 Sa 분조 계산식에 근일점 천문변수를 고려하지 않아서, 두 프로그램 간에 약 78°의 지각 차가 났으며, 이들 진폭 차이는 1 cm 이하였다. 우리나라 연안에서는 Sa 조화상수가 해마다 크게 다르므로, 조위 예측 정확도와 관련하여 안정적인 조화상수 산출에 필요한 적절한 자료 길이를 결정하기 위해 관측자료 길이(1년, 2년, 3년, 5년, 9년, 19년)에 따른 인천 조위관측소의 Sa 조화상수 값의 변동성을 살펴보았다. 대표성 있는 Sa 조화상수를 구하기 위해서 조화분해를 수행할 때 5~9년 동안의 관측자료를 사용하면 조화상수 예측오차가 상당히 줄어들며, 19년 자료를 사용 것이 가장 바람직하다는 결론을 얻었다. Sa 분조의 진폭은 각 해역별로 다른 해양·대기 환경 특성에 의해 서해안에서 15.0~18.6 cm, 제주도를 포함한 남해안에서 10.7~17.5 cm이었으며, 울릉도를 포함한 동해안에서 10.5~13.0 cm이었다. 울릉도 등 동해 일부 해역을 제외하고 우리나라 연안에서 Ssa 분조의 영향으로 인해 연중 최고(최저) 해수면 높이가 발생하는 시기가 늦어(빨라)져서 해수면의 계절변화가 시간적으로 비대칭적인 특성을 보였다. 끝으로, 월평균 해수면, 대기압 보정 해수면, 비부피 높이 간 관계로부터 해수면의 해해변화와 계절변화의 비대칭성에 대기압 효과와 해수밀도가 가장 큰 영향을 끼친다는 사실을 확인하였다.

조류 조화상수의 월변동성 완화 방법 고찰

변도성 한국해양과학기술원 2011 Ocean and Polar Research Vol.33 No.3

This is a preliminary study of the feasibility of obtaining reliable tidal current harmonic constants, using one month of current observations, to verify the accuracy of a tidal model. An inference method is commonly used to separate out the tidal harmonic constituents when the available data spans less than a synodic period. In contrast to tidal constituents, studies of the separation of tidal-current harmonics are rare, basically due to a dearth of the long-term observation data needed for such experiments. We conducted concurrent and monthly harmonic analyses for tidal current velocities and heights, using 2 years (2006 and 2007) of current and sea-level records obtained from the Tidal Current Signal Station located in the narrow waterway in front of Incheon Lock, Korea. Firstly, the l-year harmonic analyses showed that, with the exception of M2 and S2 semidiurnal constituents, the major constituents were different for the tidal currents and heights. K1, for instance, was found to be the 4th major tidal constituent but not an important tidal current constituent. Secondly, we examined monthly variation in the amplitudes and phase-lags of the S2 and K1 current-velocity and tide constituents over a 23-month period. The resultant patterns of variation in the amplitudes and phase-lags of the S2 tidal currents and tides were similar, exhibiting a sine curve form with a 6-month period. Similarly, variation in the K1 tidal constant and tidal current-velocity phase lags showed a sine curve pattern with a 6-month period. However, that of the K1 tidal current-velocity amplitude showed a somewhat irregular sine curve pattern. Lastly, we investigated and tested the inference methods available for separating the K2 and S2 current-velocity constituents via monthly harmonic analysis. We compared the effects of reduction in monthly variability in tidal harmonic constants of the S2 currentvelocity constituent using three different inference methods and that of Schureman (1976). Specifically, to separate out the two constituents (S2 and K2), we used three different inference parameter (i.e. amplitude ratio and phase-lag diggerence) values derived from the 1-year harmonic analyses of current-velocities and tidal heights at (near) the short-term observation station and from tidal potential (TP), together with Schureman's (1976) inference (SI). Results from these four different methods reveal that TP and SI are satisfactorily applicable where results of long-term harmonic analysis are not available. We also discussed how to further reduce the monthly variability in S2 tidal current-velocity constants.

병자호란 시기 강화도 함락 당일 염하수로의 조석과 조류 추산

변도성,김효원,구범진 한국과학사학회 2017 한국과학사학회지 Vol.39 No.3

On 16 February 1637, Qing troops landed on Ganghwa Island and occupied Ganghwa Castle. According to the conventional narrative, a few Joseon warships bravely fought in vain to deter the enemy from crossing the shallow, narrow Yeomha Waterway while the main fleet cowardly ran away. A close investigation of firsthand accounts of this battle, however, reveals that no Joseon warships blocked this waterway during the Qing ferryboats’ advance. Here the question arises: What kept Joseon’s naval warships from entering this waterway while the Qing boats were able to cross? In exploring possible answers, Joseon's records indicate that the presence and timing of strong tidal currents might have been a crucial obstacle to the warships’ movement. Given the substantive differences in accounts between Joseon and Qing, this paper attempts to verify which account is more accurate, by hindcasting the paleo-tidal currents and tides (PTCT) of the day via two methods: a conventional harmonic prediction method and a correct tidal species modulation with tidal constant correction method. The PTCT results in general, and the timing of the hindcast high tide and slack water period (around 10:30 am) in particular, tally with the Joseon account. Moreover, our results provide new evidence to support the detailed reconstruction of events surrounding the Qing troops’ 1637 landing operation.

국내 대표 해양·수산 과학논문 분석을 통한 우리나라 주변 바다 이름표기에 대한 제언

변도성,최병주,BYUN, DO-SEONG,CHOI, BYOUNG-JU 한국해양학회 2018 바다 Vol.23 No.3

We grouped the names attributed to the seas surrounding the Korean Peninsula in maps published in two major Korean ocean and fisheries science journals over the period from 1998 to 2017: the Journal of the Korean Society of Oceanography (The Sea) and the Korean Journal of Fisheries and Aquatic Science (KFAS). The names attributed to these seas in maps of journal paper broadly were classified into three groupings: (1) East Sea and Yellow Sea; (2) East Sea, Yellow Sea, and South Sea; or (3) East Sea, West Sea and South Sea. The name 'East Sea' was dominantly used for the waters between Korea and Japan. In contrast, the water between Korea and China has been mostly labelled as 'Yellow Sea' but sometimes labelled as 'West Sea'. The waters between the south coast of Korea and Kyushu, Japan were labelled as either 'Korea Strait' or 'South Sea'. This analysis on sea names in the maps of 'The Sea' and 'KFAS' reveals that domestic researchers frequently mix geographical and international names when referring to the waters surrounding the Korean Peninsula. These inconsistencies provide the motivation for the development of a basic unifying guideline for naming the seas surrounding the Korean Peninsula. With respect to this, we recommend the use of separate names for the marginal seas between continental landmasses and/or islands versus for the coastal waters surrounding Korea. For the marginal seas, the internationally recognized names are recommended to be used: East Sea; Yellow Sea; Korea Strait; and East China Sea. While for coastal seas, including Korea's territorial sea, the following geographical nomenclature is suggested to differentiate them from the marginal sea names: Coastal Sea off the East Coast of Korea (or the East Korea Coastal Zone), Coastal Sea off the South Coast of Korea (or the South Coastal Zone of Korea), and Coastal Sea off the West Coast of Korea (or the West Korea Coastal Zone). Further, for small or specific study areas, the local region names, district names, the sea names and the undersea feature names can be used on the maps.

국립해양조사원 해양예측시스템 소개 (I): 현업 운영 전략, 외부 해양·기상 자료 내려 받기 및 오류 알림 기능

변도성,서광호,박세영,정광영,이주영,최원진,신재암,최병주,BYUN, DO-SEONG,SEO, GWANG-HO,PARK, SE-YOUNG,JEONG, KWANG-YEONG,LEE, JOO YOUNG,CHOI, WON-JIN,SHIN, JAE-AM,CHOI, BYOUNG-JU 한국해양학회 2017 바다 Vol.22 No.3

이 노트는 국립해양조사원이 5년(2012~2016년)간에 걸쳐 지역해(동해, 황 동중국해) 수치예측시스템을 구축하여 자동으로 끊임없이 운영하면서 확보한 기술들 중 다음 3가지를 담고 있다. (1) 끊임없이 3일 해양예측 자료를 생산하기 위한 전략, (2) 매일 특정시각에 외부 해양 기상자료(HYCOM, NOAA/NCEP GFS)를 안정적으로 내려 받는 방법과 (3) 해양예측시스템 운영자들이 휴대전화 단문 메시지 서비스(Short Message Service)를 이용하여 해양예측시스템 수행 시 발생하는 시스템 오류를 신속하게 파악할 수 있는 기능에 관하여 기술하였다. 이들 기본 기술과 운영시스템 구성의 기본 개념은 지역해와 연안 해양 수치예측시스템을 자동으로 운영하는 체계를 구축하는 데 있어서 유용하게 사용될 것이다.