• Title/Summary/Keyword: Sea-Level Change

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Change of Regional Atmospheric Circulation Related with Recent Warming in the Antarctic Peninsula (남극반도의 최근 온난화와 관련된 지역적 대기순환의 변화)

  • Lee, Jeong-Soon;Kwon, Tae-Yong;Lee, Bang-Yong;Yoon, Ho-Il;Kim, Jeong-Woo
    • Ocean and Polar Research
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    • v.25 no.4
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    • pp.503-518
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    • 2003
  • This study examines the relationship among temperature, wind, and sea level pressure to understand recent warming in the vicinity of the Antarctic Peninsula. To do this, the surface air temperature, NCEP/NCAR reanalysis wind data and sea level pressure data for the period of 40 years are analyzed. The 40-year surface air temperature data in the Antarctic Peninsula reveals relatively the larger warming trends for autumn and winter than other seasons. The variability of the surface air temperature in this region is compared with that of the regional atmospheric circulation. The surface air temperature is positively correlated with frequency of northwesterlies and negatively correlated with frequency of southeasterlies. This relation is more evident in the northern tip of the Antarctic Peninsula for autumn and winter. The trend analysis of wind frequency in the study area shows increasing and decreasing trends in the frequency of northwesterlies and southeasterlies, respectively, in the northwestern part of the Weddell Sea for autumn and winter. And also it is found that these winds are closely related with decreasing of sea level pressure in the southeastern region of the Antarctic Peninsula. Furthermore from the seasonal variation of sea level pressure in this area, it may be presumed that decreasing of sea level pressure in the southeastern region of the Antarctic Peninsula is related with warming in the vicinity of the Antarctic Peninsula for autumn and winter. Therefore it can be explained that recent warming in the vicinity of the Antarctic Peninsula is caused by positive feedback mechanism, that is, the process that warming in the vicinity of the Antarctic Peninsula can lead to the decrease of sea level pressure in the southeastern region of the Antarctic Peninsula and these pressure decrease in turn lead to the variation of wind direction in northwestern part of Weddell Sea, again the variation of wind direction enhances the warming in the Antarctic Peninsula.

Pattern Analysis of Sea Surface Temperature Distribution in the Southeast Sea of Korea Using a Weighted Mean Center (가중공간중심을 활용한 한국 남동해역의 표층수온 분포 패턴 분석)

  • KIM, Bum-Kyu;YOON, Hong-Joo;KIM, Tae-Hoon;CHOI, Hyun-Woo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.3
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    • pp.263-274
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    • 2020
  • In the Southeast Sea of Korea, a cold water mass is formed intensively in summer every year, causing frequent abnormal sea conditions. In order to analyze the spatial changes of sea surface temperature distribution in this area, ocean fields buoy data observed at Gori and Jeongja and reanalyzed sea surface temperature(SST) data from GHRSST Level 4 were used from June to September 2018. The buoy data were used to analyze the time-series water temperature changes at two stations, and the GHRSST data were used to calculate the daily SST variance and weighted mean center(WMC) across the study area. When the buoy's water temperature was lowered, the variance of SST in the study area trend to increase, but it did not appear consistently for the entire period. This is because GHRSST is a reanalysis data that does not reflect sensitive changes in water temperature along the coast. As such, there is a limit to grasping the local small-scale water temperature change in the coast or detecting the location and extent of the cold water zone only by the statistical variance representing the SST change in the entire sea area. Therefore, as a result of using WMC to quantitatively determine the spatial location of the cold water mass, when the cold water zone occurred, WMC was located in the northwest sea area from the mean center(MC) of the study area. This means that it is possible to quantitatively identify where and to what extent the distribution of cold surface water temperature appears through SST's WMC location information, and we could see the possibility of WMC's use in detecting the scale of cold water zones and the extent of regional spread in the future.

Study of the Correlation Between Diatom and Environmental Variables for Palao-Sealevel Reconstruction in the Korea Peninsula: Case Study of the Eastern Tidal Flat of Gomso Bay (한반도 고해수면 변동 복원을 위한 규조-환경변수 상관관계 연구: 곰소만 동부 조간대 지역을 대상으로)

  • Kim, Jeong-Yun;Yoon, Soon-Ock;Yang, Dong Yoon;Hwang, Sang ill
    • Journal of The Geomorphological Association of Korea
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    • v.24 no.2
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    • pp.79-90
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    • 2017
  • This study investigated the correlation between the diatom community and the environmental variables on the tidal flat surface of the eastern part of Gomso Bay in the West coast of Korea in order to utilize the quantitative sea level record as a basic data. 24 sediment samples at 10cm intervals downstream of the Galgok Stream were used for diatom analysis, grain size analysis and CCA. As a result of diatom analysis, marine diatoms dominated at lower altitudes and the ratio of diatoms to fresh water diatoms and brackish diatoms increased toward upland. As a result of CCA, the contribution of environmental variables was analyzed as 25.3% at altitude, 21.6% at sand, 13.3% at skewness, etc. This means that altitude above sea level has the greatest influence on the diatom composition in the tidal flat surface. It suggests that the contribution of environmental variables at altitude above sea level can be used as a basic data for the quantitative records for reconstruction of paleo-sea level.

Holocene Sea Level Reflected from Marine Terrace in Geoje Island and its Influences on Coastal Morphogenesis (거제도 동부해안에서 파악되는 홀로세 고해수준면과 지형발달과정)

  • YANG, Jae-Hyuk
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.1
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    • pp.101-112
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    • 2011
  • Coastal terrace was developed at 7.2m height near Shinchon village in Geoje Island. It is located on the east side of southern coast in Korean Peninsula, where sea-level changes caused by ebb and flow of the tide, embayment are relatively low. Due to the breccia layer by mass-movement, dark grayish clayey formation, marine origin's rounded gravel are deposited sequentially in a cross-section of coastal terrace, so it provides a good example which understand Holocene sea level changes to determine the effect on the various sedimentary environments. For the purpose of identifying the morphogenetic process, Grain size, Roundness, XRD, AMS dating analysis was attempted. As a result, after last glacial age, Holocene sea level rise to +5.6m(4,740±100yrs BP). At that time, various geomorphological features are considered to be formed.

Global Wanning Effect on Marine Environments and Measure Practices against Global Wanning (지구 온난화에 따른 해양환경 변화와 대책)

  • Kim, Do-Hee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.16 no.4
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    • pp.421-425
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    • 2010
  • It has been mown that the global warming has an effectet on marine ecosystem and marine environments. Then, fisherman's activity and fishing production were decreased by changing of marine plankton composition and increasing of harmful marine organisms such as jellyfish, starfish and green laver bloom. Harmful red tides algae bloom and the deserted sea bottom often occurred due to increasing of sea water temperature and sea level rising in Korea. In this report, the cause and mechanism of the global warming phenomenon and it's effect on marine environment and marine ecosystem were introduced, and measures against global warming were suggested

Numerical Simulation of Tsunamis that Affected the Coastal Zone of East Sea (동해연안에 영향을 미친 지진해일의 수치시뮬레이션)

  • Kim, Do-Sam;Kim, Ji-Min;Lee, Kwang-Ho
    • Journal of Ocean Engineering and Technology
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    • v.21 no.6
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    • pp.72-80
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    • 2007
  • The tsunami that resulted from the Central East sea Earthquake, which registered 7.7 on the Richter scale, that occurred over the entire water region in Akita on May. 26, 1983 and the tsunami that was triggered by the Southwest off Hokkaido Earthquake (7.8 on the Richter scale) that occurred in Southwest off Hokkaido on July 12, 1993 are representative cases that led to considerable damage in life and property, not only in Japan but also in Korea. In this study, multi-grid method was used in order to reproduce sufficiently the shoaling effect that occurs as water depth becomes shallow in the shallow water region and moving boundary condition was introduced to consider the runup in the coastal region. For the tsunamis that exerted considerable effect on the East Sea coast of Korea that were caused by the Central East Sea Earthquake in 1983 and the Southwest off Hokkaido Earthquake in 1993, characteristics like water level rise and propagation in the East Sea coast will be examined using numerical simulations. At the same time, these values will be compared with observed values. In addition, maximum water level rise and change in the water level with respect to time that were caused by the tsunamis were examined at each location along the East sea coast. Usefulness of numerical analysis was verified by comparing with observed values.

Analysis on Winter Atmosphereic Variability Related to Arctic Warming (북극 온난화에 따른 겨울철 대기 변동성 분석 연구)

  • Kim, Baek-Min;Jung, Euihyun;Lim, Gyu-Ho;Kim, Hyun-Kyung
    • Atmosphere
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    • v.24 no.2
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    • pp.131-140
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    • 2014
  • The "Barents Oscillation (BO)", first designated by Paul Skeie (2000), is an anomalous recurring atmospheric circulation pattern of high relevance for the climate of the Nordic Seas and Siberia, which is defined as the second Emperical Orthogonal Function (EOF) of monthly winter sea level pressure (SLP) anomalies, where the leading EOF is the Arctic Oscillation (AO). BO, however, did not attracted much interest. In recent two decades, variability of BO tends to increase. In this study, we analyzed the spatio-temporal structures of Atmospheric internal modes such as Arctic Oscillation (AO) and Barents Oscillation (BO) and examined how these are related with Arctic warming in recent decade. We identified various aspects of BO, not dealt in Skeie (2000), such as upper-level circulation and surface characteristics for extended period including recent decade and examined link with other surface variables such as sea-ice and sea surface temperature. From the results, it was shown that the BO showed more regionally confined spatial pattern compared to AO and has intensified during recent decade. The regional dipolelar structure centered at Barents sea and Siberia was revealed in both sea-level pressure and 500 hPa geopotential height. Also, BO showed a stronger link (correlation) with sea-ice and sea surface temperature especially over Barents-Kara seas suggesting it is playing an important role for recent Arctic amplification. BO also showed high correlation with Ural Blocking Index (UBI), which measures seasonal activity of Ural blocking. Since Ural blocking is known as a major component of Eurasian winter monsoon and can be linked to extreme weathers, we suggest deeper understanding of BO can provide a missing link between recent Arctic amplification and increase in extreme weathers in midlatitude in recent decades.

Analysis on the Legal Impacts of Sea-Level Rise for the Application of the UN Convention on the Law of the Sea (해수면 상승이 유엔해양법협약 적용에 미치는 영향 분석)

  • Yong Hee Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.2
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    • pp.147-159
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    • 2023
  • Sea level rise due to climate change is an increasing concern for the international community, and especially for coastal States. In case of regression of the coastal line or inundations of maritime features, including islands, the questions of whether coastal States are under an obligation to redraw their baseline and the outer limits of their maritime jurisdiction and of whether the existing maritime boundary treaties should be terminated are raised. This article reviews the arguments raised by the Small Island Developing States, International Law Association, and International Law Commission and suggests a solution within the current legal framework of the Law of the Sea through an interpretation of the existing provisions of the UNCLOS focusing on the legal issues relating to the Law of the Sea.

The Changing Process of the Tidal Landforms in Hampyeung Bay, Southwest Korea (함평만의 간석지 해안지형의 변화)

  • KIM, Nam-Shin;LEE, Min-Boo
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.4
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    • pp.223-233
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    • 2011
  • The aims of this study is about distribution characteristics of tidal coastal landforms, and that changing process in the Hampyeung Bay, which has a semi-enclosed bay like basin shape without inflow of stream, the mouth of open sea is narrow and forms with wide ends toward inland sea. The source of deposits are moved materials by tidal currents and from coastal slopes. Main landform elements of study area consist of tidal flat, tidal channels, intertidal sand bar, sea cliffs, and sea terrace. Tidal flats is classified with mud flat and mixed flat by grain size composition. Mud flats have developed at the shoreline area that tidal flat is closed to the continuity of gentle slope, and mixed flat developed at the foot of the sea cliffs and sea terraces. Quaternary deposits were identified in the coastal materials sedimented by the sea-level change. According to the analysis of grain size composition during last ten years, sands and silt has increased 2% and 6% respectively, clay has been decreased by 9%. The concaved tidal flats are colonized by salt plants. Areal changes of salt plants expanded near four times from 2.4km2 at the year 2001 to 9.3km2 at the year 2009. During the same periods, mean grain size became coarser from 6.5φ to 4.5φ at the salt plants area.

Observation on Structural Change of Low Level Atmosphere due to Effect of Sea Breeze (해풍 효과에 의한 저층대기구조 변화의 측정)

  • 전병일;김유근
    • Journal of Environmental Science International
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    • v.5 no.4
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    • pp.441-451
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    • 1996
  • The surface meteorological and upper layer meteorological observation carried out to investigate influences of sea breeze effect on lower layer atmosphere at Gori nuclear power plant for 29∼30 July, 1996. According to surface meteorological data, the inflow of sea breeze was occurred 11:30 on 29 July, 10:30-on 30 July, respectively, at observation site. And the meteorological tower data showed that wind direction of sea breeze was identified as south-westerly, and wind speed of 58 m was 2 times stronger than that of 10 m. It is notworthy that surface inversion layer which built from the night time to daybreak of next day was not broken off by seab reeze's inflow for daytime, and strong inversion layer observed at 47∼243 m with moderately stable class (F) by URC. It was found that strong stable layer of potential temperature appeared at that layer, maximum relative humidity observed at the bottom of inversion layer and maximum mixing ratio observed in the low of inversion layer.

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