• Title/Summary/Keyword: Sea-water

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Pacific Equatorial Sea Surface Temperature Variation During the 2015 El Niño Period Observed by Advanced Very-High-Resolution Radiometer of NOAA Satellites

  • Lee, Seongsuk;Yi, Yu
    • Journal of Astronomy and Space Sciences
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    • v.35 no.2
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    • pp.105-109
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    • 2018
  • El $Ni{\tilde{n}}o$ is the largest fluctuation in the climate system, and it can lead to effects influencing humans all over the world. An El $Ni{\tilde{n}}o$ occurs when sea surface temperatures in the central and eastern tropical Pacific Ocean become substantially higher than average. We investigated the change in sea surface temperature in the Pacific Ocean during the El $Ni{\tilde{n}}o$ period of 2015 and 2016 using the advanced very-high-resolution radiometer (AVHRR) of NOAA Satellites. We calculated anomalies of the Pacific equatorial sea surface temperature for the normal period of 1981-2010 to identify the variation of the 2015 El $Ni{\tilde{n}}o$ and warm water area. Generally, the warm water in the western tropical Pacific Ocean shifts eastward along the equator toward the coast of South America during an El $Ni{\tilde{n}}o$ period. However, we identified an additional warm water region in the $Ni{\tilde{n}}o$ 1+2 and Peru coastal area. This indicates that there are other factors that increase the sea surface temperature. In the future, we will study the heat coming from the bottom of the sea to understand the origin of the heat transport of the Pacific Ocean.

Prospects on International Coorperation for the Environmental Protection of the Yellow Sea. (황해의 환경보전을 위한 국제협력연구의 현황과 전망)

  • 이광우
    • 한국해양학회지
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    • v.28 no.4
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    • pp.332-338
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    • 1993
  • The Yellow Sea is a marginal sea, surrounded by Chinese Continent and Korean Peninsula, with wide continental shelves and long coastlines. And the Yellow Sea is abundant with living resources and with coastal areas for leisure and aesthetic qualities. However, the Yellow Sea being a semi-enclosed water body, its water quality has been recently deteriorated due to rapid industrialization and urbanization of the coastal countries. Since marine pollution is transboundary, the needs for international cooperation among China, North Korea, Japan, Russia and Korea are urgent for the environmental protection of the Yellow Sea. The objectives of the present paper are to review the on-going research and to proposed the future prospects on international cooperation for the protection of water qualities of the Yellow Sea.

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Sea Level Variations at Kerguelen Island in the South Indian Ocean by the Satellite Data(ARGOS) and Meteorological Data(METEO)

  • Yoon, Hong-Joo
    • Korean Journal of Remote Sensing
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    • v.16 no.2
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    • pp.117-133
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    • 2000
  • We studied the sea level variations at Kerguelen island in the South Indian Ocean with ARGOS data and meteorological data during about 1 year(May 1993~April 1994) through using filter, spectral analysis, coherency and phase, and found characteristics for the two oceanic signal levels(detided oceanic signal level, h$_{detided}$ and seasonal oceanic level, h$_{corr.ib}$). The forms of atmospheric pressure variations are good agreed to between ARGOS data and meteorological data in the observed periods. This Kerguelen area shows the inflow of an air temperature(gain of a radiant heat) into the sea water and the stagnation of high atmospheric pressure bands in summer, and the outflow of a sea water temperature(loss of sensible and latent heat) toward the atmosphere and the stagnation of low atmospheric pressure bands in winter. The seasonal difference of sea level between summer and winter is about 1.6cm. Both the detided oceanic signal level(h$_{detided}$) variation and the inverted barometer level(h$_{ib}$) variation have a strong correlation for T>1day period bands. The characteristics of h$_{detided}$ variation are not decided by the influence of any meteorological distributions (atmospheric pressure), but the influence of other factors(bottom water temperature) for T>2days periods bands. h$_{corr.ib}$ plays a very important role of sea level variation in the observed periods (especially T>about 180days period bands).

Transplantation of Koelreuteria paniculata by Sea Current (모감주나무의 해류에 의한 전파)

  • 이영노
    • Journal of Plant Biology
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    • v.1 no.1
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    • pp.11-20
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    • 1958
  • I. Assumption: Mo-kam-ju, Koelreuteria paniculata is a woody plant mainly cistributed over Northern China. Its sporadic growth along the beaches of Korea and Japan is assumed to have been sowed by the seeds transported adrift on the current across the ocean. II. Use and Growth of the Plant: In China, this plant has been cultivated from early times mainly at temples, it seeds being used as rosaries, its flowers for yellow dyes and medicine for the eyes, and its leaves for black dyes. In Korea and Japan, these plants have been cultivated at temples and used as the material for rosaries. No natural growth of these plants was reported until 1919. III. Discoveries: In this domestic area, Dr. Chung Tae Hyun discovered the plant on the beach between Cho-Do and Chang-san-kot, Hwang-Hae Prov. in 1920. The reporter discovered them on the beach at Buk-Ni, Duk-jok-Do in 1948, at An-Hung in 1956 and on the beach at An-min-Do in 1957. In the Japan area, it was discovered for the first time twenty years ago, mainly along the coast line of the Japan Sea and some along the eastern coast line, at Subo, Yamaguchi Prefecture facing the Pacific Ocean. IV. Study and Experiment: A. Seed The seed coat is thick, non-permeable and floatable. A number of seeds were immersed in artificial sea water and fresh water separately. The seeds remained there for a hundred and forty-five (145) days from April 6, 1957 to August 29, 57. Thirty one seeds out of the fifty immersed in salt water and twenty seeds out of the fifty immersed in fresh water remained on the surface of the water, proving them to be non-permeable to both sea and fresh water. Of course, these had retained their germinating capabilities. Five (5) seeds out of twenty from the fresh water and six (6) out of thirty-one from the sea water were successfully germinated after a hole had been drilled in the seed coat and they had been planted. Thus their floating capability, non-permeability and germinating capability after a possible 145 day trip on the flowing currents has been proved satisfactory according to the assumption made above. B. Current As shown in the Data 2 and 3, the sea current initiated in the Pohai Sea flows westward down along the coast line of Korea reaching the southern part during the autumn and winter seasons. This fact also is in favor of the reporter's assumption. V. Discussion and Conclusion: The reporter concludes that, as discussed above, Koelreuteria paniculata which originates in Northern China is transported adrift on the flowing sea current to our western coast line, and also the coast lines of Shantung and Kuangtung of China and it is germinated on the sandy beaches forming new plants. Thus, the seeds drifted down on the southern beach of Korea and have been transported to the Japanese coast, adrift on the Tae-Ma current. Upon fruition, the seeds of the plants which settle on the coasts of western Korea and Japan will migrate to new places. It can be, however, assumed that while the thickness and nonpermeability of the coat enables the long travel in the water, this also can compose a difficulty in germination, consequently in developing a new distribution of this species.

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A Study on the Decision for External Water Level of a River Considering Sea Level Rise (해수면 상승을 고려한 하천 외수위 결정에 관한 연구)

  • Choo, Tai Ho;Yun, Gwan Seon;Kwon, Yong Been;Ahn, Si Hyung;Kim, Jong Gu
    • The Journal of the Korea Contents Association
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    • v.16 no.4
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    • pp.604-613
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    • 2016
  • The sea level of the Earth is rising approximately 2.0mm per year (global average value) due to thermal expansion of sea water, melting of glaciers and other causes by global warming. However, when it comes to design a river, the standard of design water level is decided by analyzing four largeness tide value and harmonic constant with observed tidal water level. Therefore, it seems the external water level needs to consider an increasing speed of the seawater level which corresponds to a design frequency. In the present study, the hourly observed tidal water level targeting 47 tidal stations operated by Korea Hydrographic and Oceanographic Administration (KHOA) from beginning of observation to 2015 per hour has been collected. The variation of monthly and yearly and increasing ratio have been performed divided 4 seas such as the Southern, East, Western, and Jeju Sea. Also, the external water level existing design for rivers nearby a coast was been reviewed. The current study could be used to figure out the cause of local seawater rise and reflect the external water level as basic data.

A study of sea level measurement using GPS buoy (GPS 부의를 이용한 해수면 관측에 관한 연구)

  • Park, Un-Yong;Oh, Chang-Soo;Lee, Dong-Rak;Hong, Jung-Soo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.85-88
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    • 2007
  • Sea level fluctuation present a direct influence to those who live near the coast. The importance of monitoring sea level is evident. Therefore, various techniques have been employed for sea level measurements such as the coastal water level gauges, satellite altimetry and GPS buoy. Especially, GPS buoys have been used to measure water levels, atmospheric parameter and other physical conditions in sea, tide correction, the altimeter range calibration, ocean environment. In this paper, we will mainly concentrate on the kinematic technique for GPS buoy to measure the sea level. A test was carried out to test the method proposed in this paper, which made use of a GPS buoy equipped to monitor the sea level in Busan. We have executed to analysis about applications of GPS buoy.

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The Change Detection of SST of Saemangeum Coastal Area using Landsat and MODIS (Landsat TM과 MODIS 영상을 이용한 새만금해역 표층수온 변화 탐지)

  • Jeong, Jong-Chul
    • Journal of Environmental Impact Assessment
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    • v.20 no.2
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    • pp.199-205
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    • 2011
  • The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

Monthly Wind Stress and Wind Stress Curl Distributions in the Eastern Sea(Japan Sea) (동해상의 월별 바람응력 및 바람응력컬 분포)

  • 김철호;최병호
    • Water for future
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    • v.19 no.3
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    • pp.239-248
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    • 1986
  • Monthly wind stress, wind stress curl and volume transport stream functions are computed in the Eastern Sea(Japan Sea) based upon observed wind and atmospheric pressure data respectively. The presented two results show different distributios on locality and season but as common features the results reveal the northwesterly surface wind stress \ulcorner 새 the monsoon in winter, south to southwesterly wind stress \ulcorner 새 the southerly wind in summer and strond anticyclonic curl in the northern part on the Eastern Sea(Japan Sea) in winter. In the distributions obtained from the sea level atmospheric pressure data, the maximum value of the wind stress and of curls of small scales are shown off the southeast coast of Siberia and northeast coast of Korea. Volume transport distributions obtained from the Sverdrup relationship suggest that the strong northward boundary current can be formed along the northeast coast of Korea in winter and weak southward boundary current in summer.

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Hydrographic Analysis of Surface Water Using Radium Isotopes Signature in the East and South China Sea in Summer (여름철 동중국해 및 남중국해 표층수의 Ra 동위원소를 이용한 수계분석)

  • Yang, Han-Soeb;Lee, Tong-Sup
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.4
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    • pp.305-311
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    • 1999
  • This study aims to decipher surface water mass interaction in summer in the South China Sea and East China Sea by radium isotope distribution pattern. Salinity and activity ratio of radium ($^{228}Ra/^{226}Ra$) showed gradual changes, which were adequate to apply simple two end-member mixing between Kuroshio surface water and Changjiang Dilute Water for the East China Sea and the former and Nearshore Diluted Watermass (NDW) for the South China Sea. Two tracer methods, salinity and Ra isotope ratio, were compared for East China Sea. Results showed remarkable consistency for waters near Kuroshio, however, discrepancy were noticeable after Tsushima Warm Current branching. Mixing with subsurface waters may cause the discrepancy. When mixed with subsurface waters, salts and radium isotope ratio are expected to be biased in opposite direction, i. e. prone to underestimate the fraction of less saline water in the case of salts and vice versa for Ra isotope ratio. Taking the mean values of two different results seems more realistic to estimate fraction of end-members.

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First Record of Two Cold-Water Jellyfishes Aurelia limbata and Parumbrosa polylobata (Scyphozoa: Semaeostomeae: Ulmaridae) in Korean Coastal Waters

  • Chang, Soo-Jung;Kim, Jung Nyun;Yoon, Won-Duk;Ki, Jang-Seu
    • Animal Systematics, Evolution and Diversity
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    • v.32 no.4
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    • pp.272-280
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    • 2016
  • Most scyphomedusae jellyfishes recorded in Korean waters are temperate and subtropical species. In the present study, two cold-water jellyfishes from Korean waters are first described. Scyphomedusae were collected from the coasts of Gangneung and Ulsan of the East Sea, and Boryeong, and the eastern area of the Yellow Sea from June 2006 to May 2015. Scyphomedusae collected in Ulsan and Gangneung were identified morphologically as Aurelia limbata Brandt, 1835. Their umbrella was 250-500 mm in width and 30-50 mm in height; the exumbrella was white and the subumbrella was dark brown in color. The vascular system was complex with anastomosed branches. Individuals of this species lived at about 6.6-9.9℃ and 30-50 m depth in Korean waters. Scyphomedusae collected from the center of the Yellow Sea and from Boryeong were identified as Parumbrosa polylobata Kishinouye, 1910. Their umbrella was disc-shaped, 80-200 mm in width and 20-40 mm in height. Its milky white gonads could be seen through the transparent exumbrella. The stomach cavity was round and flat with four interradial cavities connected by subgenital cavities, and the four oral arms were bifurcated and spear-head shaped. Individuals were found at about 6.4-10.0℃ and 40-90 m depth in Korean waters. The identities of both species were confirmed by molecular analysis using nuclear ribosomal DNA sequences.