• Title/Summary/Keyword: east sea

Search Result 3,314, Processing Time 0.034 seconds

Investigation of Change in Air-Sea CO2 Exchange over the East China Sea using Biogeochemical Ocean Modeling (생지화학모델링을 이용한 동중국해 해양-대기 CO2교환량의 변화 연구)

  • Park, Young-Gyu;Choi, Sang-Hwa;Yeh, Sang-Wook;Lee, Jung-Suk;Hwang, Jin-Hwan;Kang, Seong-Gil
    • Ocean and Polar Research
    • /
    • v.30 no.3
    • /
    • pp.325-334
    • /
    • 2008
  • A biogeochemical model was used to estimate air-sea $CO_2$ exchange over the East China Sea. Since fresh water discharge from the Changjiang River and relevant chemistry were not considered in the employed model, we were not able to produce accurate results around the Changjiang River mouth. This factor aside, the model showed that the East China Sea, away from the Changjiang River mouth, takes approximately $1.5{\sim}2\;mole\;m^{-2}yr^{-1}$ of $CO_2$ from the atmosphere. The model also showed that biological factors modify the air-sea $CO_2$ flux by only a few percent when we assumed that biological activity increased two-fold. Therefore, we can argue that the biological effect is not strong enough over this area within the framework of the current phosphate-based biological model. Compared to the preindustrial era, in 1995 the East China Sea absorbed $0.4{\sim}0.8\;mole\;m^{-2}yr^{-1}$ more $CO_2$. If warming of the sea surface is considered, in addition to the increase in atmospheric $CO_2$ concentration, by 2045 the East China Sea would absorb $0.2{\sim}0.4\;mole\;m^{-2}yr^{-1}$ less $CO_2$ compared to the non-warming case.

An Informetric Analysis on the Notation of East Sea Recorded in Academic Journals ('동해' 표기에 대한 계량적 분석)

  • Han, Jong Yup
    • Journal of the Korean Society for information Management
    • /
    • v.32 no.1
    • /
    • pp.23-41
    • /
    • 2015
  • This study worked on the qualitative analysis about nomenclature East Sea by the record type in researches related to East Sea shown in the scientific journals. Here in this study, the way of marking is classified as three: 'sole notation of East Sea', 'sole notation of Sea of Japan', and 'simultaneous notation of both'. Based on a total of 4,192 selections from Web of Science DB, the analysis was followed up for change in time series by the notation type, notation type according to the nation that authors belong to, difference in research topic, impact factor, collaboration in research, and co-authorship network. The result turned out in this work that the sole notation of Sea of Japan accounted for the largest portion. It also showed that the rates of sole notation of East Sea and simultaneous notation have kept increasing continuously since the 1990s. Hub nations regarding the research of East Sea is five including Japan, Russia, Korea, USA, and China. In the case of sole notation of Sea of Japan, active collaboration studies are performed in USA, Russia, and China with a focus in Japan. In the case of sole notation of East Sea and simultaneous use, the research rate is relatively high in USA and Japan with a focus in Korea. As to the co-authorship network in the sole notation of Sea of Japan, sort of a "giant component" among different groups has been set up and through which the collaborative works are actively underway. However, it was found that the research of sole notation of East Sea is dispersed into small groups on the base of relevant individual institution.

Abnormal Cooling before and after the 1982-1983 and 1997-1998 ENSO Events in the Korean East Sea Water (1982-1983년.1997-1998년 엘니뇨현상 전후 한국동해역에서의 이상 저수온 현상)

  • Hong, Chul-Hoon
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.41 no.4
    • /
    • pp.294-300
    • /
    • 2008
  • Abnormal cooling of the Korean East Sea Water(KESW) in the East Sea before and after the 1982-1983 and 1997-1998 ENSO events is examined using bimonthly routine observation data from the National Fisheries Research and Development Institute of Korea for the period 1965 to 2002. The KESW, which occupies roughly a region between the Korean Peninsula and west of approximately $131^{\circ}E$, showed extreme cold-state years(1981 and 1996) prior to the two strongest ENSO events of the last half-century. Inter-annual bimonthly mean anomalies at 100 m in the KESW region were $-3.10^{\circ}C\;and\;-3.41^{\circ}C(SD=1.4^{\circ}C)$ in 1981 and 1996, respectively. These results suggest that extreme cooling of the KESW may be a prelude to very strong ENSO events through large-scale teleconnections.

Dinoflagellate Cyst Assemblages in the Surface Sediments from the Northwestern East China Sea

  • Cho Hyun-Jin;Matsuoka Kazumi;Lee Joon-Baek;Moon Chang-Ho
    • Fisheries and Aquatic Sciences
    • /
    • v.4 no.3
    • /
    • pp.120-129
    • /
    • 2001
  • Thirty-six dinoflagellate cysts, representing 15 genera were identified in the surface sediments obtained from the northwestern East China Sea. Three cyst morphotypes found in this survey have not previously been described in the East China Sea and adjacent waters: Seleno­pemphix sp. 2, Selenopemphix sp. 3 and Trinovantedinium sp. 1. In the northwestern East China Sea, Operculodinium centrocarpum, Spiniferites bulloideus and ellipsoidal cysts of Alexandrium were commonly observed. Moreover, it was recognized that the ellipsoidal cysts of Alexandrium, whose motile cells of A tamarense and/or A catenella are responsible to paralytic shellfish poisoning, distributed not only restricted to the coastal areas but also to the offshore stations far from the Changjiang River mouth.

  • PDF

Abyssal Currents Driven by a Local Wind Forcing through Deep Mixed Layer: Implication to the East Sea

  • Seung, Young-Ho
    • Ocean Science Journal
    • /
    • v.40 no.2
    • /
    • pp.101-107
    • /
    • 2005
  • A simple analytical model is considered in an attempt to demonstrate a formation mechanism of the abyssal current in the East Sea. In this model, the abyssal currents are driven by wind through an outcrop region and flow along closed geostrophic contours. A rough estimate of the abyssal currents, arrived at by applying this model to the region of deep mixing in the East Sea, gives currents comparable to those observed, although there is an uncertainty in the surface area of the outcrop region. It seems that the spin-up of deep water by wind forcing through the region of deep winter mixing is, at least partly, an important contribution to the formation of the abyssal currents in the East Sea.

Numerical Simulations of 1983 Central East Sea Tsunami at Imwon: 1. Propagation across the East Sea (임원에서의 1983년 동해 중부 지진해일 수치모의: 1. 동해에서의 전파)

  • Cho, Yong-Sik;Lee, Ho-Jun
    • Journal of Korea Water Resources Association
    • /
    • v.35 no.4 s.129
    • /
    • pp.443-452
    • /
    • 2002
  • The propagation of the 1983 Central East Sea Tsunami recorded as the most devastating tsunami during last decades across the East Sea is numerically simulated in this study h numerical model based on the shallow~water equations is employed. The physical dispersion is somewhat replaced by the numerical dispersion resulting from the leap-frog scheme. Traveling times of leading tsunamis are estimated and wane rays are calulated based on the Munk and Arthur(1952).

A New Free-Living Marine Nematode, Chaetonema longicorpus sp. nov. (Enoplida: Anoplostomatidae) from a Subtidal Zone of the East Sea, Korea

  • Lee, Hyo Jin;Lee, Heegab;Rho, Hyun Soo
    • Animal Systematics, Evolution and Diversity
    • /
    • v.38 no.4
    • /
    • pp.205-213
    • /
    • 2022
  • A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.