• Title/Summary/Keyword: Northern Korean peninsula

Search Result 303, Processing Time 0.02 seconds

Tidal and tide-induced residual currents around Hampyung Bay and Hajae Peninsula by numerical simulation (수치모형을 통한 함평만과 해제반도 주변해역의 조류 및 조석잔차류 분포)

  • CHOO, Hyo-Sang
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.56 no.2
    • /
    • pp.114-125
    • /
    • 2020
  • In order to understand the currents around Hampyung Bay and Haeje Peninsula, 2D numerical simulations for tidal currents and tide-induced residual currents were carried out. Dominant semidiurnal tidal currents have reversing form and flow NNE-SSW from northern Haeje Peninsula to Songi Island, E-S at northern Haeje Peninsula and NNW-SSE in Hampyung Bay. In flood, a part of currents from Imja Island~Nakwhol Island flow along the main stream flowing northeast at offshore region and the rest flow into Hampyung Bay flowing east along the northern coast of Haeje Peninsula. In ebb, currents from Hampyung Bay flow west along the northern coast of Haeje Peninsula and run together with the main stream flowing southeast at offshore region. The currents create an anticyclonic circulation in flood and a cyclonic circulation in ebb around Haeje Peninsula including Hampyung Bay. Tidal currents are accumulated on Doripo which located at the entrance of Hampyung Bay and show high current velocities. Tidal currents and tide induced residual currents are weak at the inside of Hampyung Bay which has narrow entrance, shallow water depth and wide intertidal zone. An anticyclonic eddy is formed around Gaksi Island as a result of tide induced residual currents. In northern coast of Haeje Peninsula, slow constant currents flow east. It is expected that a gradual change of sediment and an increase of flushing time for suspended materials are carried by tidal currents occurring in Hampyung Bay.

Rayleigh Wave Group Velocities with an Enhanced Resolution in the Northern Korean Peninsula

  • Jung, Heeok;Jang, Yong-Seok
    • Journal of the Korean earth science society
    • /
    • v.37 no.5
    • /
    • pp.286-294
    • /
    • 2016
  • Using a method suggested by Yanovskaya, we obtained Rayleigh wave group velocities with a resolution of $1.0^{\circ}{\times}1.0^{\circ}$ in a period range between 10 and 80 s in and around the Korean peninsula. Both regional and distant earthquake data sets were used together in analysis of group velocities. The resolution of the group velocity maps has been remarkably enhanced by the method, especially in the sparse/non-station region in the northern Korean peninsula. Some qualitative geophysical information was inferred from the group velocity maps. In the East Sea, the slow group velocities at periods longer than 40 s suggest the existence of an oceanic lithosphere at depths of 50-70 km, assuming 4 km/s of S wave velocity at a period of 40 s. On the other hand, a thick lithosphere can be inferred in the continental area from the fast group velocities at periods longer than 50 s. For most periods, the group velocities change rapidly over a short distance of about 200 km across the eastern coast of Korean peninsula, which may suggest a rapid change in the thickness of lithosphere in this area.

New distribution record of northern lineage plant of Stellaria filicaulis(Caryophyllaceae) from South Korea

  • Dong-Pil Jin;Chae Eun Lim;Sunhee Sim;Jin Dong Lee;Inbae Lee;Kwuidong Jung;Jung-Hyun Kim
    • Journal of Species Research
    • /
    • v.12 no.4
    • /
    • pp.299-306
    • /
    • 2023
  • A northern lineage plant, Stellaria filicaulis (Caryophyllaceae), was newly found in Yeoncheon-gun, Gyeonggi-do of South Korea. This species is distributed in China, Japan, Korea, Mongolia, and Russia. On the Korean Peninsula, St. filicaulis, however, has been known to grow in North Korea. Species identification was confirmed using morphological characteristics and DNA sequence data, while comparing with materials obtained from herbarium specimens. Stellaria filicaulis is distinguished from St. longifolia by having smooth surface of stem, petals about twice longer than sepals. On the neighbor-joining tree, St. filicaulis formed a clade, and the species is closely related to St. longifolia of the Parviflorae clade. Details of the morphological characters, the type specimens, voucher specimens data, and photographs of St. filicaulis in South Korea are presented. In addition, it is likely that a new habitat will be found by plant biodiversity field surveys through the middle part of the Korean Peninsula. Further research is needed to determine its population size, distribution, and threats, as well as identify appropriate locations for conservation collection of germplasm.

A study on ancient Japanese costume (일본고대복식에 관한 연구 - 한반도의 경향을 중심으로 -)

  • 이은주
    • Journal of the Korean Home Economics Association
    • /
    • v.23 no.2
    • /
    • pp.1-11
    • /
    • 1985
  • RESULTS : Considering the archaeological evidences, it is velieved that the southern culture centered in KuSu and the Nothern Culture centered in the centeral Japan, specially at the estern Japan, existed together with the culture come through the southern regions and northern regions of Japanese Islands in Jomon Culture and Yayoi Culture period. As the center of territory moved from KuSu to GiNae in Tumulus Culture period, two-pieced style of the northern people who have already there became prevalent. The costume of Tumulus Culture period was developed from the coexistence f southern style and northern style to the merge of the two styles by the nomads come from Korean Peninsula. The riding costume was propagated by Koreans, and the style used in Korean Peninsula was more deeply influenced to the costume of the ruling class. The costume of Asuka Culture and MakuHo Culture period succeeds the costume of Tumulus Culture period without wide difference. But the costume of Korean Peninsula lied more deeply as the root of Japanese Costume. While the costume of the ruling class was changed into Tang's style, the costume of the masses was under the influence of the costume of Korean Peninsula. It became the base of current Japanese Folk Costume.

  • PDF

Prediction of Soybean Growth in the Northern Region based on Growth Data from the Southern Regions of the Korean Peninsula (한반도 남부지역 생육 데이터 기반 북방지역 콩 생육 예측)

  • Ye Rin Kim;Jong hyuk Kim;Il Rae Rho
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.68 no.4
    • /
    • pp.285-293
    • /
    • 2023
  • This study was conducted to determine the sowing limit period and predict growth in the northern region based on accumulative temperature for each growth stage of soybean cultivated in the southern regions of the Korean Peninsula. First, the results of a demonstration test in the central region (Yeoncheon) of the Korean Peninsula were very similar to the predicted and actual values on the date by growth stage obtained through cultivation. This method was then applied to seven agricultural climatic zones in the northern Korean Peninsula. The results predicted that regardless of ecotype, soybean could be grown and harvested in the southern and northern parts of Mt. Suyang, south of the East Sea, and in the central and northern inland areas. However, it was predicted that no ecotype could be grown and harvested normally in the northern alpine region. Furthermore, north of the East Sea, the prediction indicated that early and mid-maturing cultivars could be grown and harvested normally, but middle-late maturing cultivars appeared to lack the number of growth days. The sowing limit period also varied depending on the ecotype, although it was reached earlier as higher latitudes were approached; the period ranged from May 16 to June 26 in the northern and southern parts of Mt. Suyang, north and south of the East Sea, and central and northern inland areas. Furthermore, all ecotypes of the northern alpine region, as well as mid-late maturing cultivars in the north of the East Sea, were predicted to be unable to grow normally owing to the lack of number of days required for soybean growth and development.

Estimation for Changes of Net Primary Productivity and Potential Natural Vegetation in the Korean Peninsula by the Global Warming (地球 溫暖化에 따른 韓半島의 純一次生産力과 潛在自然植生의 變化 推定)

  • Kim, Jeong-Un;Kil, Bong-Seop
    • The Korean Journal of Ecology
    • /
    • v.19 no.1
    • /
    • pp.1-7
    • /
    • 1996
  • The net primary productivity and potential natural vegetation in the Korean peninsula in the 21st century were estimated by the Miami model and thermal climate, respectively, based on 148 meteorological data sets. In the 21st century, the distribution range of the net primary produtivity in the Korean peninsula was estimated as 1,050 g $DM{\cdot}m^{-2}{\cdot}yr^{-1}~2,050g\;DM\cdot m^-2\cdot yr^{-1}.\; These\; values\; increased\; by\; 200g\; DM\cdot m^{-2}\cdot yr^{-1}\;on\;northern\;part\;and\;400g\; DM\cdot m^{-2}\cdot yr^{-1}$ on southern part compared with that of the present century. The potential natural vegetation in the Korean peninsula in the 21st century will change into the followings:coniferous forest on Mt. Paektu area, deciduous broadleaf forest on northern part, and evergreen broadleaf forset on southern part.

  • PDF

WRF Sensitivity Experiments on the Formation of the Convergent Cloud Band in Relation to the Orographic Effect of the Korean Peninsula (한반도 지형이 대상수렴운의 생성에 미치는 영향에 관한 WRF 민감도 실험)

  • Kim, Yu-Jin;Lee, Jae Gyoo
    • Atmosphere
    • /
    • v.25 no.1
    • /
    • pp.51-66
    • /
    • 2015
  • This study was conducted to perform various sensitivity experiments using WRF (Weather Research and Forecasting) model in order to determine the effects of terrains of the Korean Peninsula and the land-sea thermal contrast on the formation and development of the convergent cloud band for the cases of 1 February 2012. The sensitivity experiments consist of the following five ones: CNTL experiment (control experiment), and TMBT experiment, BDMT experiment and ALL experiment that set the terrain altitude of Taeback Mountains and Northern mountain complex as zero, respectively, and the altitude of the above-mentioned two mountains as zero, and LANDSEA experiment that set to change the Korean Peninsula into sea in order to find out the land-sea thermal contrast effect. These experiment results showed that a cold air current stemming from the Siberian high pressure met the group of northern mountains with high topography altitude and was separated into two air currents. These two separated air currents met each other again on the Middle and Northern East Sea, downstream of the group of northern mountains and converged finally, creating the convergent cloud band. And these experiments suggested that the convergent cloud band located on the Middle and Northern East Sea, and the cloud band lying on the southern East sea to the coastal waters of the Japanese Island facing the East Sea, were generated and developed by different dynamical mechanisms. Also it was found that the topography of Taeback Mountains created a warm air advection region due to temperature rise by adiabatic compression near the coastal waters of Yeongdong Region, downstream of the mountains. In conclusion, these experiment results clearly showed that the most essential factor having an effect on the generation and development of the convergent cloud band was the topography effect of the northern mountain complex, and that the land-sea thermal contrast effect was insignificant.

Determination of Lateral Variations for Pn Velocity Structure Beneath the Korean Peninsula Using Seismic Tomography (지진토모그래피 (Seismic Tomography) 방법을 이용한 한반도 하부 Pn 속도 구조의 수평분포 결정)

  • Kim, So Gu;Lee, Seoung Kyu
    • Economic and Environmental Geology
    • /
    • v.30 no.6
    • /
    • pp.625-635
    • /
    • 1997
  • A back projection algorithm is applied to 216 Pn travel time measurements to image lateral variations of compressional velocity in the uppermost mantle in the Korean Peninsula. We obtained an average P-velocity value for the uppermost mantle of $7.90{\pm}0.18km/sec$, and an average mantle P-velocity gradient of $5.3{\times}10^{-3}s^{-1}$ for the Korean Peninsula. The final 3-D velocity image in the uppermost mantle is characterized by a low-velocity (about $7.77{\pm}0.12km/sec$) region in the southeast area of the Korean peninsula, which is called 'Kyongsang Basin' and by high-velocity(${\geq}8.08km/sec$) region in the northern area of the Korean Peninsula(Hamkyong and Pyongan provinces). The crustal thicknesses are calculated for the 10 subregions. The crustal thickness of the northern part(${\geq}39^{\circ}N$) of the Korean Peninsula is 33.0-36.0 km, on the contrary, that of the southern part(< $39^{\circ}N$) is 30.7~33.7 km. The velocity image obtained in this study is somewhat consistent with previous S-P travel time studies and gravity studies.

  • PDF

Comparison on the Time of Occurrence of Major Rice Insect Pests Based on Growing Degree Day in Northern Part of Korean Peninsula (북방농업지대에서 유효적산온도를 이용한 벼 해충의 발생시기 비교)

  • Kim, Soon-Il;Uhm, Ki Baik;Jin, Da-Yong;Park, Hyung Man
    • Korean journal of applied entomology
    • /
    • v.58 no.3
    • /
    • pp.239-249
    • /
    • 2019
  • This study was carried out to compare on the time of occurrence of 6 major rice insect pests [Lissorhoptrus oryzophilus Kusche, Oulema oryzae Kuwayama, Sogatella furcifera (Horvath), Nilaparvata lugens Stal., Cnaphalocrocis medinalis (Guenee), Mythimna separata Walker] in northern part of the Korean peninsula. Using growing degree days of the insects, we evaluated the number of occurrence generations and the time of occurrence. Over-wintering insects such as L. oryzophilus and O. oryzae showed different occurrence periods in northern regions. The occurrence period of the first generation adults was later in northeast regions than in Korean middle regions and more later both in northern alpines and in northern parts of east sea. In addition, the first adults of S. furcifera, N. lugens, C. medinalis, and M. separata occurred between June and early August. However, from late August to September, these insects showed the different occurrence periods in northern regions. Especially, the second adults of N. lugens were not occurred and the second to third generation adults of S. furcifera, C. medinalis, and M. separata showed similar occurrence properties. Based on these properties, the occurrence of major rice insect pests will be less in northeast regions, northern regions of east sea, northern inlands, and northern alpines of the Korean peninsula. However, comparing with their occurrences in northern regions of Gyenonggi and Gangwon provinces, the rice insect pests may show similar occurrence pattern in mid-korean mountains except for pyunggang and yangduk regions as well as in the southern and northern regions of Suyang-san.

Distribution of Indicator Plant of Climate Change in Major Islands of the Korean Peninsula (한반도 주요 도서 지역의 기후변화 지표 식물 분포)

  • Kim, Hyun Hee;Mizuno, Kazuharu;Lee, Ho Sang;Koo, Jae Gyun;Kong, Woo Seok
    • Journal of Environmental Science International
    • /
    • v.30 no.1
    • /
    • pp.29-43
    • /
    • 2021
  • This study analyzed the status of climate-change indicator plants native to the main islands of the Korean peninsula, while elucidating their distribution characteristics. Information on flora from over 129 island locations, comprising more than 100 species of native plants, was collected, compiled into a database, and utilized as raw data. The distribution of 193 climate-change indicator plants was confirmed. The distribution area of broadleaf evergreen trees and ferns, including Mallotus japonicus and Cyrtomium falcatum, was relatively wide. In contrast, the distribution of common northern plants such as Corydalis turtschaninovii and Malus baccata was limited. If global warming persists, northern plant distribution is expected to decrease rapidly in the Korean Peninsula island region, while the northern limit line of the southern plants is expected to migrate further northward. During this process, it is likely that the plant congregation structure and species diversity within the island region will change dynamically. In this study, comparative analyses between species and regions were conducted by assessing the relative frequency of their occurrence, and six types of botanical geographic distribution patterns were noted.