• Title/Summary/Keyword: Coastal features

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The Yellow Sea Warm Current and the Yellow Sea Cold Bottom Water, Their Impact on the Distribution of Zooplankton in the Southern Yellow Sea

  • Wang, Rong;Zuo, Tao
    • Journal of the korean society of oceanography
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    • v.39 no.1
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    • pp.1-13
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    • 2004
  • The Yellow Sea Warm Current (YSWC) and the Yellow Sea Cold Bottom Water (YSCBW) are two protruding features, which have strong influence on the community structure and distribution of zooplankton in the Yellow Sea. Both of them are seasonal phenomena. In winter, strong north wind drives southward flow at the surface along both Chinese and Korean coasts, which is compensated by a northward flow along the Yellow Sea Trough. That is the YSWC. It advects warmer and saltier water from the East China Sea into the southern Yellow Sea and changes the zooplankton community structure greatly in winter. During a cruise after onset of the winter monsoon in November 2001 in the southern Yellow Sea, 71 zooplankton species were identified, among which 39 species were tropical, accounting for 54.9 %, much more than those found in summer. Many of them were typical for Kuroshio water, e.g. Eucalanus subtenuis, Rhincalanus cornutus, Pareuchaeta russelli, Lucicutia flavicornis, and Euphausia diomedeae etc. 26 species were warm-temperate accounting for 36.6% and 6 temperate 8.5%. The distribution pattern of the warm water species clearly showed the impact of the YSWC and demonstrated that the intrusion of warmer and saltier water happened beneath the surface northwards along the Yellow Sea Trough. The YSCBW is a bottom pool of the remnant Yellow Sea Winter Water resulting from summer stratification and occupy most of the deep area of the Yellow Sea. The temperature of YSCBW temperature remains ${\leq}{\;}10^{\circ}C$ in mid-summer. It is served as an oversummering site for many temperate species, like Calanus sinicus and Euphaisia pacifica. Calanus sinicus is a dominant copepod in the Yellow Sea and East China Sea and can be found throughout the year with the year maximum in May to June. In summer it disappears in the coastal area and in the upper layer of central area due to the high temperature and shrinks its distribution into YSCBW.

Establishment of Korean Environmental Sensitivity Index Map (ESI Map 구축 연구)

  • Sung H. G.;Lee H. J.;Lee M. J.;Kang C. G.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.6 no.4
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    • pp.3-12
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    • 2003
  • Due to the high demand on energy resources accompanied by continuing industrialization and urbanization, the world marine transportation of crude and product oils is being gradually increased. In Korea, we are exposed to the large-scale marine oil spill accidents because a very large oil tanker of 300,000 tonnage must enter Korean Ports every day to meet the domestic demand on oils. Although we are exerting our strength to reduce the probability of marine oil pollution accidents, a unrestorable oil spill is to occur owing to human errors, severe weather conditions, or combined causes. Thus, area contingency plan equipped with appropriate management system for response and restoration for the worst case discharge scenario must be entirely prepared to protect mine environments and coastal resources. In particular, we are focusing on the Environmental Sensitivity Index Map(ESI Map) to reduce the environmental consequences of both spills and clean-up efforts by specifying protection Priorities in advance and identifying in-situ response strategies. In this paper, Korean ESI Map is introduced with brief definition of sensitivity to oiling and main features of the software developed hitherto.

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Variations in the downwelling diffuse attenuation coefficients in the northern South China Sea

  • Wang, Guifen;Cao, Wenxi;Yang, Dingtian;Xu, Dazhi
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.905-908
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    • 2006
  • The diffuse attenuation coefficient for downwelling irradiance $(K_d({\lambda}))$ is an important parameter for ocean studies. Based on the optical profile data measured during three cruises in the northern South China Sea in autumn from 2003 to 2005, variations in the $K_d({\lambda})spectra$ were analyzed. The variability of $K_d({\lambda})$ shows much distinct features both in magnitude and spectra shape. The $K_d({\lambda})value$ are much higher in costal waters than that of open oceanic waters and the blue-to-green(443/555) ratios of $K_d({\lambda})$ tends to increases with the chlorophyll a concentration ([Chl a]) from open ocean to coastal waters. These characteristics can be explained primarily by the increasing of $a_{w+p}(433)/a_{w+p}(555)$ with [Chl a]. In the short waveband, the relation between $K_d({\lambda})-K_w({\lambda})$ and [Chl a] can be well described by a power law function, suggesting the large contribution of phytoplankton to the variations in $K_d({\lambda})$. As for the spectral model of the diffuse attenuation coefficient, there are good linear relationships between $K_d(490)$ and $K_d({\lambda})$ at other wavelengths, with the slope parameter and the intercept following linear functions within the spectral range $412{\sim}555$ nm. These variabilities of $K_d({\lambda})$ provided much useful information for us to study the bio-optical properties in the northern South China Sea.

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Larval morphology of Laemonema nana Taki (Moridae) (짧은수염대구 (Laemonema nana Taki; 국명신칭) 자치어의 형태 발달)

  • Kim, Sung;Yoo, Jae-Myung
    • Korean Journal of Ichthyology
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    • v.12 no.1
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    • pp.33-37
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    • 2000
  • A total of 28 Laemonema nana larvae, 1.4~10.5 BL (body length), were collected by bongo net and trawl-shaped fish larvae net in the coastal area of Cheju Island during 1998~1999. This species was found in around sea of Cheju Island, Korea Strait and southwestern East Sea. This paper describes morphological features of these specimens throughout their development. 1) The soft ray of fin appeared at about 4.5 mm BL and attained to a fixed number at about 6.8 mm BL. 2) There were two large pigments in the head of larvae less than 4 mm BL. 3) A large pigment in the middle of tail appeared at about 2 mm BL was spread to the caudal peduncle at about 9 mm BL. 4) Two large pigment in the base of anal fin appeared at about 2 mm BL were spread out 2/3 of anal fin to caudal fin at about 9 mm BL. 5) A new Korean name "Chal-Bun-Su-Yum-Dae-Gu" is proposed for this species.

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Application of Soil's Self-Decontamination Ability to Contaminated Ground (흙의 자체정화능력을 이용한 오염된 토양정화)

  • Jeong, Jin-Seob;Jhung, Jhung-Kwon;Kim, Tae-Hyung;Fang, Hsai-Yang
    • Journal of Korean Society on Water Environment
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    • v.22 no.4
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    • pp.632-638
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    • 2006
  • There are numerous approaches available to cleanup a contaminated surface and subsurface ground currently in use, however, these methods all classify the decontamination after the contamination has penetrated into the soil masses and is costly. Unlike these approaches, in this study, utilization of soil's self-decontamination ability by rearranging and preplanning of the topographical features and surface and subsurface drainage systems for the potential contamination sites before or during contamination process has been considered as an another cleanup method. Step by step explanations on why and how to develop the self-decontamination procedure is proposed in detail. Two examples are presented including contaminated saltwater intrusion along a coastal region and control or prevention of radioactive toxic radon gas ($^{222}Rn$) in residential areas. The effectiveness of the proposed systems to these two examples using the soil's self-decontamination ability is well illustrated.

A Study on the Local Climate in the Vicinity of Duckyang Bay , Korea (득량만일원의 국지기상 환경의 특성에 관한 연구)

  • 김유근
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.28 no.4
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    • pp.398-411
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    • 1992
  • The characteristics of local climate in the vicinity of Duckyang Bay have been investigated with the analysis of the surface observation data of Gohug District and the aerological data of Kwangju. In principal features of local climate, the annual range in temperature appeared identical with the mean value(24~$25^{\circ}C$) of the south coastal area, and evaporation from April to September was likely less than precipitation. The average speed of surface wind in Summer seemed higher than in other seasons on account of wea breeze. Relative humidity was 74%, annual average. In the mean cloud cover Summer(6.4) showed greater deal of amount than Winter(4.2). Duration of sunshine was the longest in May(268.4hrs), while the shortest in February(188.4hrs). The amount of the precipitable water was the greatest in July, whereas the least in January, and in Summer the greatest, in Autumn the second greatest, and in Spring the third greatest, and in Winter the least in consideration of seasonal orders. The Summer deviation was most remarkable around all sides. The direction of vector wind appeared the most changeable on the earth surface. At an altitude of 300mb all the winds blew west around all months. Moreover, water vapor transport was measured to be the greatest in Summer; while the least in Winter. So was the deviation of water vapor transport. And lastly frequency of occurrence of days in which a little cloud appeared(less than 5/10) was high except for Summer, when northerly winds blew; while frequency of occurrence of day plenty of clouds floated was outstandingly high at the time of strong southerly winds.

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Evaluation of Upper Ocean Temperature and Mixed Layer Depth in an Eddy-permitting Global Ocean General Circulation Model (중해상도 전지구 해양대순환 모형의 상층 수온과 혼합층 깊이 모사 성능 평가)

  • Jang, Chan-Joo;Min, Hong-Sik;Kim, Cheol-Ho;Kang, Sok-Kuh;Lie, Heung-Jae
    • Ocean and Polar Research
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    • v.28 no.3
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    • pp.245-258
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    • 2006
  • We investigated seasonal variations of the upper ocean temperature and the mixed layer depth (MLD) in an eddy-permitting global ocean general circulation model (OGCM) to assess the OGCM perfermance. The OGCM is based on the GFDL MOM3 which has a horizontal resolution of 0.5 degree and 30 vertical levels. The OGCM was integrated for 68 years using a monthly-mean climatological wind stress forcing. The model sea surface temperature (SST) and sea surface salinity were restored to the Levitus climatology with a time scale of 30 days. Annual-mean model SST shows a cold bias $(<\;-2^{\circ}C)$ in the summer hemisphere and a warm bias $(>\;1^{\circ}C)$ in the winter hemisphere mainly due to the restoring boundary condition of temperature. The model MLD captures well the observed features in most areas, with a slightly deep bias. However, in the Ross Sea and Weddell Sea, the model shows significantly deeper MLD than the climatology-mainly due to weak salinity stratifications in the model. For amplitude of seasonal variation, the model SST is smaller $(1{\sim}3^{\circ}C)$ than the observation largely due to the restoring surface boundary condition while the model MLD has larger seasonal variation $({\sim}50m)$. It is suggested that for more realistic simulation of the upper ocean structure in the present eddy-permitting ocean model, more refinements in the surface boundary condition for the thermohaline forcing and parameterization for vertical mixing are required, together with the incorporation of a sea-ice model.

UK Urban Regeneration Policy for Comprtitiveness: A Government Perspective

  • Thorpe, Keith
    • Land and Housing Review
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    • v.8 no.2
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    • pp.33-53
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    • 2017
  • The UK Government's approach to how to deliver regeneration in its towns and cities has changed considerably in recent years. Traditionally, urban regeneration policy focused on reversing physical, economic and social decline in an area where market forces would not do this without intervention. Since 2010 urban regeneration has become a vital part of the Government's approach to increasing local growth and competitiveness and building a strong and balanced economy. The current emphasis is on a place-based approach to regeneration that builds on the particular strengths of different places to drive growth and addresses the factors that hold them back. This paper outlines the key features of current UK urban regeneration policy and how interventions to support regeneration and growth are being pursued at different spatial scales to ensure all parts of the country benefit. They include pan regional initiatives like the Northern Powerhouse and Midlands Way, to groups of local authorities operating at a sub regional level (combined authorities/city regions), Local Enterprise Partnerships, and a variety of smaller scale programmes delivering regeneration in areas of economic and social decline. The paper explains some of the policy instruments and funding programmes available to support regeneration, and provides case studies of some major urban regeneration projects that illustrate the new approach including housing and infrastructure improvements like the planned High Speed Rail 2 line. These are supporting regeneration through the creation of strategic partnerships involving government, places and investors. The paper concludes with some lessons from past and future regeneration schemes to improve their effectiveness and impact on places and enhance local growth potential.

Characteristics of East Asian Cold Surges in the CMIP5 Climate Models (CMIP5 기후 모형에서 나타나는 동아시아 한파의 특징)

  • Park, Tae-Won;Heo, Jin-Woo;Jeong, Jee-Hoon;Ho, Chang-Hoi
    • Atmosphere
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    • v.27 no.2
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    • pp.199-211
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    • 2017
  • The cold surges over East Asia can be grouped to two types of the wave-train and the blocking. Recently, the observational study proposed new dynamical index to objectively identify cold surge types. In this study, the dynamical index is applied to the simulations of 10 climate models, which participate in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Focusing on assessment of cold surge simulation, we discuss characteristic of the wave-train and blocking cold surges in the climate models. The wave-train index (WI) and the blocking index (BI) based on potential temperature anomalies at dynamical tropopause over the subarctic region, the northeast China, and the western North Pacific enable us to classify cold surges in the climate models into two types. The climate models well simulate the occurrence mechanism of the wave-train cold surges with vertical structure related to growing baroclinic wave. However, while the wave-train in the observation propagates in west-east direction across the Eurasia Continent, most of the models simulate the southeastward propagation of the wave-train originated from the Kara Sea. For the blocking cold surges, the general features in the climate models well follow those in the observation to show the dipole pattern of a barotropic high-latitude blocking and a baroclinic coastal trough, leading to the Arctic cold surges with the strong northerly wind originated from the Arctic Sea. In both of the observation and climate models, the blocking cold surges tend to be more intense and last longer compared to the wave-train type.

Dimethylsulfide (DMS) in Seawater and the Overlying Atmosphere of the Masan Bay (해수 및 대기 중 DMS의 분석 : 마산만을 중심으로)

  • 김기현;오재룡;강성현;이수형;이강웅
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.4
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    • pp.495-504
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    • 1996
  • The concentrations of dimethylsulfide (DMS) were determined from both seawater and the overlying atmosphere from a station located in the Masan Bay area during a ten-day field campaign period of January 1996. The resulting data were also used to derive saturation ratios (SR) as well as sea-to-air fluxes of DMS. The concentrations and fluxes of DMS for both reservoirs varied extensively over two to three orders of magnitude: DMS in air and seawater were measured at 9 to 4,300 pptv (mean: 600 $\pm$ 1, 170, N=18) and at 0.24 to 10 nM (4.0 $\pm$ 3.4, N=13), respectively, while its fluxes were found from 0.02 to 23 mol $m^{-2} day^{-1} (3.1 \pm 6.8, N=11)$. A comparative analysis between our data and previously reported ones indicate that its atmospheric concentrations are abnormalously high, but its seawater counterparts are slightly lower than expected. In light of high pollution levels of organic-rich materials in and the associated high biological productivity of the study area, the sea-to-air-fluxes derived are notably low relative to those values typically reported from the coastal areas. These complicated features of DMS distributions/fluxes in the study site indicate that the near-by port- based anthropogenic activities from various industrial plants strongly interfere with natural processes leading to the production and release of DMS. It was however striking to find out relatively strong signals of diel cycle in its saturation ratios, concentration gradients between seawater and atmosphere, and the associated fluxes. Although it is yet difficult to provide meaningful explanations for the observed phenomena, the existence of clear diel cycle in some DMS-related parameters suggests that the natural processes may nonetheless exert important controls on the regional cycling of atmospheric sulfur species, of particular DMS.

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