1993–2018년 한반도 연안 상대해수면 수지 분석

차상철,Jo Seongbae,문재홍 한국해양과학기술원 2024 Ocean and Polar Research Vol.46 No.1

Due to physical processes varying in space and time, regional sea-level rise (SLR) significantly deviates from the global mean. Thus, understanding and quantifying the contribution of each process to regional sea-level change is crucial to prevent low-lying inundation in preparation for future ocean conditions. In this study, we assessed to what degree sterodynamic (SD) effects (i.e., density-driven steric expansion and mass redistribution due to ocean circulation), contemporary mass redistribution (CMR), and glacial isostatic adjustment (GIA) contribute relative sea-level rise around the Korean coast from 1993 to 2018, with independent observations and reanalysis datasets. The assessment showed that the tide gauge-observed SLR trend can be explained by the sum of each component at 16 of 19 locations. The major contributors to relative SLR are SD effects of 2.03±0.27 mm/yr and CMR components of 1.31±0.05 mm/yr, while GIA drives sea-level decreasing of -0.27±0.15 mm/yr on the Korean coast. It was also found that the spatial deviations of SLR are primarily caused by the SD effects. In addition, the evaluation of vertical land motion (VLM) based on altimetry and tide gauge indicates that most tide gauge locations have experienced uplift during at least altimetry period, whereas Wido station has experienced particularly high rate of subsidence that contributed to the SLR acceleration. Further examination of the impact of earth deformation due to CMR, GIA, and local process on the VLM trends demonstrated that the GIA and CMR contribute to land uplift with the average of 0.35±0.15 mm/yr and 0.17±0.05 mm/yr, respectively. On the other hand, the local processes like groundwater depletion and sediment compaction showed a wide range of variability, from -1.61 to 0.58 mm/yr, indicating a significant contribution to regional differences in vertical land motion.

앙상블 경험적 모드 분해법을 사용한 태평양의 지역별 해수면 변화 분석

차상철,문재홍 한국해양과학기술원 2019 Ocean and Polar Research Vol.41 No.3

Natural variability associated with a variety of large-scale climate modes causes regional differences in sea level rise (SLR), which is particularly remarkable in the Pacific Ocean. Because the superposition of the natural variability and the background anthropogenic trend in sea level can potentially threaten to inundate low-lying and heavily populated coastal regions, it is important to quantify sea level variability associated with internal climate variability and understand their interaction when projecting future SLR impacts. This study seeks to identify the dominant modes of sea level variability in the tropical Pacific and quantify how these modes contribute to regional sea level changes, particularly on the two strong El Niño events that occurred in the winter of 1997/1998 and 2015/2016. To do so, an adaptive data analysis approach, Ensemble Empirical Mode Decomposition (EEMD), was undertaken with regard to two datasets of altimetry-based and in situ-based steric sea levels. Using this EEMD analysis, we identified distinct internal modes associated with El Niño-Southern Oscillation (ENSO) varying from 1.5 to 7 years and low-frequency variability with a period of ~12 years that were clearly distinct from the secular trend. The ENSO-scale frequencies strongly impact on an east-west dipole of sea levels across the tropical Pacific, while the low-frequency (i.e., decadal) mode is predominant in the North Pacific with a horseshoe shape connecting tropical and extratropical sea levels. Of particular interest is that the low-frequency mode resulted in different responses in regional SLR to ENSO events. The low-frequency mode contributed to a sharp increase (decrease) of sea level in the eastern (western) tropical Pacific in the 2015/2016 El Niño but made a negative contribution to the sea level signals in the 1997/1998 El Niño. This indicates that the SLR signals of the ENSO can be amplified or depressed at times of transition in the low-frequency mode in the tropical Pacific.

위성 고도계와 해수면 재구성 자료를 이용한 기후변동성에 따른 태평양 해수면 변화

차상철,문재홍 한국해양과학기술원 2018 Ocean and Polar Research Vol.40 No.1

Previous studies have indicated a great regional difference in Sea Level Rise (SLR) in the Pacific and it has been suggested that this is linked to climate variability over the past two decades. In this study, we seek to identify the possible linkage between regional sea level and Pacific climate variability from altimetry-based sea level data (1993−2012) and further investigate how the Pacific sea level has changed spatially and temporally over the past 60 years from long-term sea level reconstruction data (1953−2008). Based on the same method as Zhang and Church (2012), the Inter-annual Climate Index (ICI) associated with the El Niño-Southern Oscillation (ENSO) and the Decadal Climate Index (DCI) associated with Pacific Decadal Oscillation (PDO) are defined and then the multiple variable linear regression is used to analyze quantitatively the impact of inter-annual and decadal climate variability on the regional sea levels in the Pacific. During the altimeter period, the ICI that represents ENSO influence on inter-annual time scales strongly impacts in a striking east-west “see-saw mode” on sea levels across the tropical Pacific. On the other hand, the decadal sea level pattern that is linked to the DCI has a broad meridional structure that is roughly symmetric in the equator with its North Pacific expression being similar to the PDO, which largely contributes to a positive SLR trend in the western Pacific and a negative trend in the eastern Pacific over the two most recent decades. Using long-term sea level reconstruction data, we found that the Pacific sea levels have fluctuated in the past over inter-annual and decadal time scales and that strong regional differences are presented. Of particular interest is that the SLR reveals a decadal shift and presents an opposite trend before and after the mid-1980s; i.e., a declining (rising) trend in the western (eastern) Pacific before the mid- 1980s, followed by a rising (declining) trend from the mid-1980s onward in the western (eastern) Pacific. This result indicates that the recent SLR patterns revealed from the altimeters have been persistent at least since the mid-1980s.

近代 帝國主義의 歷史的 性格

車相哲 연세대학교 대학원 1974 원우론집 Vol.2 No.1

Abstract This article is written for the purpose of readjusting the historical meaning of modern Imperialism since 1870. We can make out the general character of the early commercial Imperialism in the reflection of the mercantilism and the adventurous pursuit of discoveries and conquests of the New World. But the Industrial Imperialism which is raised its head from the late nineteenth century strived ardently for the intensification of political dominance over underdeveloped countries, especially in Africa and Asia, to pursue the economic interests. As J. A. Hobson pointed out alrealy, modern Imperialism is the endless endeavour of the great controllers of industry to broaden the channel for the flow of their surplus wealth by seeking foreign markets and foreign investment to take off the goods and capital they cannot sell or use at home. In conclusion, modern Imperialism is defined as the political activities for the expansion of dominance of modern nation-slates, and the expansionism carried out by the collusion of the development of capitalism and the aspirtion for national prosperity. In other words, we call find out historical characteristics of modern Imperialism in 'the internationalization of capitalism' which have matured since the late nineteenth century.

올바른 교육감 선출로 교육을 살립시다!

차상철 열린전북 2000 열린전북 Vol.12 No.-

이승만과 한미합의의사록의 체결

차상철 육군군사연구소 2013 군사연구 Vol.- No.135

As theCold Wargotintensified in the early 1950s,PresidentSyngman Rhee madeagooduseof‘limitandchance’thattheRepublicofKoreafacedinprocess offierytalkswiththeU.S.inordertoconcludethemutualdefensetreatyandthe agreedminutebetweentheROK andtheU.S. PresidentRheeadmittedtheharsh realitythatKoreahadtoplaceitsmainrelianceontheUnitedStates’militaryand economicalsupportbut,atthesametime,healsowellknew thatKoreaalsotook significantpartinthescheme.Korea’sroleintheNortheastAsiaeconomywhich met with Japanese reconstruction policy, Korea’s military strategic value,psychological importance that Korea stood as an anticommunist nation in confrontation against communism contributed to the conclusion of a positive agreementwiththeU.S. A sharpreinforcementofROK armyandequipmentmodernizationarecompulsive and urgentassignmentforPresidentRheefacing thecommunistthreatincluding NorthKoreaandresurgenceofJapaneseexpansionism.ThereforePresidentRhee's determinationandnegotiationstrategytowardtheU.S.werefirm andelaborate.In such a long and rough process ofconclusion,PresidentRhee restrained U.S.’political‘flexibility’andfinallysucceededtoattainmostofhisrequirements.Onthe otherhand,theEisenhoweradministrationhadtorevisemuchofitsoriginalplan andpolicy.TheU.S.gaveseriousconsiderationto‘exclude’PresidentRhee.Buthe alreadybecameasymbolicfigureofan‘anticommunist’. Asthefirstpresidentofanewly-bornindependentstate,PresidentRheebelieved thatnationalsecurityshouldpreferentiallycomefirstbeforepoliticaldemocracyand economicaldevelopment.TheROK-U.S.allianceformed by theconclusion ofthe mutualdefense treaty and the agreed minute guaranteed the U.S.’support to Korea’ssurvivalandsecurity.Sincethen theROK-U.S.alliancehasdeterredthe recurrenceofwarin theKorean peninsula and hasmaintained a “peaceunder tension.”Furthermoreithasbecamea strong foundation fortheindustrialization anddemocratizationofKorea 냉전이 심화되어 갔던 1950년대 초반 이승만 대통령은 한미상호방위조약과 한미합의의사록의 체결을 달성하기 위한 치열한 대미협상과정에서,대한민국이 직면한 ‘한계와 기회’를 효과적으로 활용했다.이승만은한국의 생존을 확보하기 위하여 미국의 군사적,경제적 지원에 의존할수밖에 없는 냉엄한 현실을 인정했지만,동시에 한국이 미국에게도 매우중요하다는 사실을 잘 알고 있었다.미국의 일본 재건정책과 맞물린 동북아시아 경제에서의 한국의 역할,그리고 한국의 군사전략적 가치와 공산주의 세력과의 대결구도에서의 ‘반공’국가 한국이 갖는 심리적 중요성은 이승만의 대미협상력을 높이는데 크게 기여했다. 북한을 포함한 공산주의 세력의 심각한 위협과 일본 팽창주의의 ‘부활’을 심히 우려했던 이승만에게 있어서,한국군의 대폭 증강과 장비현대화는 반드시 실현해야만 하는 시급하고도 절실한 과제였다.따라서 대미협상에 임하는 이승만의 결의와 협상전략도 단호하고 치밀했다.한미합의의사록의 체결을 둘러싼 길고도 험난한 협상과정에서 이승만은 미국의 정책적 ‘유연성’을 제한시킴으로써,마침내 자신의 요구조건의 상당부분을 관철시키는데 성공했다.반면에 아이젠하워 행정부는 원래의 계획과 정책을 상당부분 수정할 수밖에 없었다.미국은 이승만의 ‘제거’를검토했지만,실행에 옮길 수는 없었다.이승만은 이미 ‘반공’의 상징적인인물이 되어 있었기 때문이었다. 신생독립국가의 초대 대통령으로서,이승만은 대한민국의 생존을 확보할 수 있는 군사적 안보가 정치적 민주주의와 경제적 발전보다도 우선해야 한다고 믿었다.한미상호방위조약과 한미합의의사록의 체결로 성립된 한미동맹으로,이승만은 한국의 생존과 안보를 미국으로부터 보장받는데 성공했다.한미동맹은 정전협정이 체결된 이후 지금까지 한반도에전쟁의 재발을 억제하고,‘긴장 속의 평화’가 유지될 수 있었던 원천이되었을 뿐만 아니라 나아가 한국의 산업화와 민주화를 위한 탄탄한 토대가 되었다.

1941~1945년 미국의 한국정책

차상철 한국인문사회과학회 1988 현상과 인식 Vol.12 No.1

원전 계획예방정비 공정과 방사선관리

차상철,안태호,김상훈,박철완 대한방사선방어학회 2021 대한방사선방어학회 학술발표회 논문요약집 Vol.2021 No.11

고해상도 해양순환모델을 활용한 제주도 주변해역의 해수유동 특성

차상철,문재홍 한국해양과학기술원 2020 Ocean and Polar Research Vol.42 No.3

With the increasing demand for improved marine environments and safety, greater ability to minimize damages to coastal areas from harmful organisms, ship accidents, oil spills, etc. is required. In this regard, an accurate assessment and understanding of current systems is a crucial step to improve forecasting ability. In this study, we examine spatial and temporal characteristics of current systems in the adjacent seas of Jeju Island using a high-resolution regional ocean circulation model. Our model successfully captures the features of tides and tidal currents observed around Jeju Island. The tide form number calculated from the model result ranges between 0.3 and 0.45 in the adjacent seas of Jeju Island, indicating that the dominant type of tides is a combination of diurnal and semidiurnal, but predominantly semidiurnal. The spatial pattern of tidal current ellipses show that the tidal currents oscillate in a northwest-southeast direction and the rotating direction is clockwise in the adjacent seas of Jeju Island and counterclockwise in the Jeju Strait. Compared to the mean kinetic energy, the contribution of tidal current energy prevails the most parts of the region, but largely decreases in the eastern seas of Jeju Island where the Tsushima Warm Current is dominant. In addition, a Lagrangian particle-tracking experiment conducted suggests that particle trajectories in tidal currents flowing along the coast may differ substantially from the mean current direction. Thus, improving our understanding of tidal currents is essential to forecast the transport of marine pollution and harmful organisms in the adjacent seas of Jeju Island.

이승만의 미국인식 : 형성과 전개

차상철 (사)한국인물사연구회 2008 한국인물사연구 Vol.9 No.-