• Title/Summary/Keyword: Eastern Coastal Region

Search Result 95, Processing Time 0.028 seconds

A Qualitative Analysis of WRF Simulation Results of Typhoon 'Rusa' Case (태풍 루사와 관련된 WRF의 수치모의 결과 분석)

  • Kim, Jin-Won;Lee, Jae Gyoo
    • Atmosphere
    • /
    • v.17 no.4
    • /
    • pp.393-405
    • /
    • 2007
  • Simulation results of WRF for the case of typhoon 'Rusa' were analyzed, comparing with observed data especially forjavascript:confirm_mark('abe', '1'); the Gangneung area around to examine its ability in numerical simulation. From the hourly precipitation time series, two peaks were found at Gangneung and Daegwallyeong, while only one peak was found from those of inland regions else. Especially, for the Yeongdong region, the first peak was directly related to spiral bands generated in front of the typhoon. Convective cells that were developed within the spiral bands moved to the eastern coastal area from the sea so that local heavy rainfall occurred in the Yeongdong region. The second peak was mainly related to the accompanying rain band of typhoon itself, topographic effect and the convergence near Gangneung area. Precipitation in Gangneung was simulated as much as about 30% of observed one. The main reason of this result came from a poor representation of wind directions in Gangneung area of WRF model. Observed wind direction was northwesterly but simulated one was nearly easterly in the area. This might shift a local heavy rainfall area downstream to the mountain area rather than the coastal area.

Current Status of Intensive Observing Period and Development Direction (집중관측사업의 현황과 발전 방향)

  • Kim, Hyun Hee;Park, Seon Ki
    • Atmosphere
    • /
    • v.18 no.2
    • /
    • pp.147-158
    • /
    • 2008
  • Domestic IOP (intensive observing period) has mostly been represented by the KEOP (Korea Enhanced Observing Period), which started the 5-yr second phase in 2006 after the first phase (2001-2005). During the first phase, the KEOP had focused on special observations (e.g., frontal systems, typhoons, etc.) around the Haenam supersite, while extended observations have been attempted from the second phase, e.g., mountain and downstream meteorology in 2006 and heavy rainfall in the mid-central region and marine meteorology in 2007. So far the KEOP has collected some useful data for severe weather systems in Korea, which are very important in understanding the development mechanisms of disastrous weather systems moving into or developing in Korea. In the future, intensive observations should be made for all characteristic weather systems in Korea including the easterly in the central-eastern coastal areas, the orographically-developed systems around mountains, the heavy snowfall in the western coastal areas, the upstream/downstream effect around major mountain ranges, and the heavy rainfall in the mid-central region. Enhancing observations over the seas around the Korean Peninsula is utmost important to improve forecast accuracy on the weather systems moving into Korea through the seas. Observations of sand dust storm in the domestic and the source regions are also essential. Such various IOPs should serve as important components of international field campaign such as THORPEX (THe Observing system Research and Predictability EXperiment) through active international collaborations.

Modification of Sea Water Temperature by Wind Driven Current in the Mountainous Coastal Sea

  • Choi, Hyo;Kim, Jin-Yun
    • Proceedings of the Korean Environmental Sciences Society Conference
    • /
    • 2003.11a
    • /
    • pp.177-184
    • /
    • 2003
  • Numerical simulation on marine wind and sea surface elevation was carried out using both three-dimensional hydrostatic and non-hydrostatic models and a simple oceanic model from 0900 LST, August 13 to 0900 LST, August 15, 1995. As daytime easterly meso-scale sea-breeze from the eastern sea penetrates Kangnung city in the center part as basin and goes up along the slope of Mt. Taegullyang in the west, it confronts synoptic-scale westerly wind blowing over the top of the mountain at the mid of the eastern slope and then the resultant wind produces an upper level westerly return flow toward the East Sea. In a narrow band of weak surface wind within 10km of the coastal sea, wind stress is generally small, less than l${\times}$10E-2 Pa and it reaches 2 ${\times}$ 10E-2 Pa to the 35 km. Positive wind stress curl of 15 $\times$ 10E-5Pa $m^{-1}$ still exists in the same band and corresponds to the ascent of 70 em from the sea level. This is due to the generation of northerly wind driven current with a speed of 11 m $S^{-1}$ along the coast under the influence of south-easterly wind and makes an intrusion of warm waters from the southern sea into the northern coast, such as the East Korea Warm Current. On the other hand, even if nighttime downslope windstorm of 14m/s associated with both mountain wind and land-breeze produces the development of internal gravity waves with a hydraulic jump motion of air near the coastal inland surface, the surface wind in the coastal sea is relatively moderate south-westerly wind, resulting in moderate wind stress. Negative wind stress curl in the coast causes the subsidence of the sea surface of 15 em along the coast and south-westerly coastal surface wind drives alongshore south-easterly wind driven current, opposite to the daytime one. Then, it causes the intrusion of cold waters like the North Korea Cold Current in the northern coastal sea into the narrow band of the southern coastal sea. However, the band of positive wind stress curl at the distance of 30km away from the coast toward further offshore area can also cause the uprising of sea waters and the intrusion of warm waters from the southern sea toward the northern sea (northerly wind driven current), resulting in a counter-clockwise wind driven current. These clockwise and counter-clockwise currents much induce the formation of low clouds containing fog and drizzle in the coastal region.

  • PDF

Low-salinity Water and Circulation in Summer around Saemangeum Area in the West Coast of Korea (하계 서해안 새만금 연안역 주변 저염수와 순환)

  • 이상호;최현용;손영태;권효근;김영곤;양재삼;정해진;김종구
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.8 no.2
    • /
    • pp.138-150
    • /
    • 2003
  • In the mid-west coast of Korea where Mankyung and Dongjin rivers discharge fresh water, Saemangeum tidal dyke of 33 km long is under construction to reclaim the very shallow estuary region of 41,000ha. Main source of freshwater in this coastal area is Keum River locating closely north of the dyke. At present, the dyke connected with Gogunsan-Gundo separates this area into three regions; northwestern, southwestern and eastern (Saemangeum) region of the dyke, and the water in Saemangeum region is exchanged through one gap in the northern dyke and two gaps in the southern dyke. We have observed distributions and structures of temperature and salinity to examine the summer circulation related with low-salinity water in this coastal area in 1998 and 1999. In the surface layer off the northern dyke a tongue-like distribution of low-salinity extends 60 km long from Keum River estuary mouth to the northwest, forming plume front bounded by offshore water. In the inner region of Saemangeum dykes salinity distributions show that two river waters are merged together and the low salinity water is deflected toward northern gap of the dyke. In the surface layer off the southern dyke we observed small tongue-like distribution of another low-salinity water extending to the north from Gomso Bay. Based on the analysis of distributions of low-salinity water and frontal structures, we can suggest an anticlockwise circulation of coastal water around the dyke, composed by the estuarine water outgoing from the inner region of the dyke through the northern dyke's gap and the inflow through two gaps of southern dyke from offshore. After completing the dyke construction, this coastal circulation around the dyke will be, however, changed because fresh water discharge of Mankyung and Dongjin rivers will be routed artificially and directly into the area offshore of the southern dyke.

Estimating distribution changes of ten coastal plant species on the Korean Peninsula (한반도 해안식물 10종의 분포 변화 추정)

  • PARK, Jong-Soo;CHOI, Byoung-Hee
    • Korean Journal of Plant Taxonomy
    • /
    • v.50 no.2
    • /
    • pp.154-165
    • /
    • 2020
  • Coastal regions are experiencing habitat changes due to coastal development and global warming. To estimate the future distribution of coastal plants on the Korean Peninsula due to climate change, the potential distribution of ten species of coastal plants was analyzed using the MaxEnt program. The study covered the eastern, western, and southern coastal areas of the Korean Peninsula. We used the distributional data of coastal plants of the East Asian region and the 19 climate variables of WorldClim 2.0. The future potential distribution was estimated using future climate variables projected from three general circulation models (CCSM4, MIROC-ESM, and MPI-ESM-LR), four representative concentration pathways (2.5, 4.5, 6.0, and 8.5), and two time periods (2050 and 2070). The annual mean temperature influenced the estimation of the potential distribution the most. Under predicted future distribution scenarios, Lathyrus japonicus, Glehnia littoralis, Calystegia soldanella, Vitex rotundifolia, Scutellaria strigillosa, Linaria japonica, and Ixeris repens are expected to show contracted distributions, whereas the distribution of Cnidium japonicum is expected to expand. Two species, Salsola komarovii and Carex kobomugi, are predicted to show similar distributions in the future compared to those in the present. The average potential distribution in the future suggests that the effects of climate change will be greater in the west and the south coastal regions than in the east coastal region. These results will be useful baseline data to establish a conservation strategy for coastal plants.

Enhancing LANDSAT TM to update the structural analysis of the Mirs Bay Basin, Hong Kong, China

  • Leung, K.F.;Vohora, V.K.;Chan, L.S.;Malpas, J.G.
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.295-297
    • /
    • 2003
  • The coastal provinces of South China have been uniquely shaped by various tectonic events. During the midlate Mesozoic tectono-thermal event, the oblique subduction of the Paleo Kula-Pacific plate beneath the Eurasian plate has created a complicated tectonic setting for the whole region. However, the mechanism of this event is not completely understood. In this paper, we discuss the advantages of using LANDSAT TM satellite imagery over a small part of the region - the Mirs Bay Basin which is largely covered by dense vegetation and where limited outcrops is seen. The use of satellite imagery complements field mapping and the result shows a prominent sinistral offset along the eastern margin of the Mirs Bay Basin, which was not previously recognized on the ground.

  • PDF

Diversity and Saline Resistance of Endophytic Fungi Associated with Pinus thunbergii in Coastal Shelterbelts of Korea

  • Min, Young Ju;Park, Myung Soo;Fong, Jonathan J.;Quan, Ying;Jung, Sungcheol;Lim, Young Woon
    • Journal of Microbiology and Biotechnology
    • /
    • v.24 no.3
    • /
    • pp.324-333
    • /
    • 2014
  • The Black Pine, Pinus thunbergii, is widely distributed along the eastern coast of Korea and its importance as a shelterbelt was highlighted after tsunamis in Indonesia and Japan. The root endophytic diversity of P. thunbergii was investigated in three coastal regions; Goseong, Uljin, and Busan. Fungi were isolated from the root tips, and growth rates of pure cultures were measured and compared between PDA with and without 3% NaCl to determine their saline resistance. A total of 259 isolates were divided into 136 morphotypes, of which internal transcribed spacer region sequences identified 58 species. Representatives of each major fungi phylum were present: 44 Ascomycota, 8 Zygomycota, and 6 Basidiomycota. Eighteen species exhibited saline resistance, many of which were Penicillium and Trichoderma species. Shoreline habitats harbored higher saline-tolerant endophytic diversity compared with inland sites. This investigation indicates that endophytes of P. thunbergii living closer to the coast may have higher resistance to salinity and potentially have specific relationships with P. thunbergii.

Atmospheric Pollutant Concentrations under the Influences of Internal Gravity Wave and Sea-Land Breeze Circulations in the Mountainous Coastal Regions (산악연안지역에서 내부중력파와 해륙풍순환 영향하의 대기오염농도)

  • Hyo Choi;Joon Choi
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
    • /
    • v.23 no.1
    • /
    • pp.18-33
    • /
    • 1995
  • Under the synoptic scale strong westerly winds flowing over the large steep mountains in the eastern coastal region, the strong downslope wind storms such as internal gravity waves should be generated in the lee-side of mountain. Int he daytime as sea breeze circulation induced by meso-scale thermal forcing from sea toward inland confines to the offshore side of coastal sites due to the eastward internal gravity waves. Thus, surface winds near the coastal seas were relatively weaker than those in the open sea or the inland sites. Evidently, two different kinds of atmospheric circulations such as an internal gravity wave circulation with westerly wind and a sea breeze circulation with both easterly wind near the sea surface and westerly in the upper level were apparently produced. Under this situation the atmospheric pollutants at Kangnung city should be trapped by two different circulations in the opposite directions and resulted in the high concentrations of Total Suspended Particles (TSP) and ozone (O3). At night a meso-scale land breeze from land toward the more intensification of westerly winds in the coastal regions. The concentrations of TSP controled by the strong surface winds blowing from the mountain side toward the coastal sea were relatively higher at night than those in the daytime case and the concentrations of O3 due to the downward transport of ozone from the upper atmosphere toward the surface were also much higher at night than during the day. Consequently, the atmospheric pollutant concentrations in the mountainous coastal region under the downslope wind storms were higher than those after and before the occurrences of wind storms.

  • PDF

Numerical Modelling Of The Coastal Upwelling Near The Poleward Edge Of The Western Boundary Current

  • An, Hui Soo
    • 한국해양학회지
    • /
    • v.16 no.1
    • /
    • pp.12-23
    • /
    • 1981
  • A numerical experiment is made in order to clarify the mechanism of the upwelling phenomenon along the coast near the poleward edge of the western boundary current. The possibility of the upwelling is suggested from the analysis of the observational data in the east of Honshu, Japan, and in the south eastern coast of Korean Peninsula. This upwelling phenomenon is very deep and can be traced to the bottom layer. The upwelling phenomenon seems to be a general oceanic feature which characterizes the region along the west coast near the poleward edge of the western boundary current. This experiment is simulating the oceanic condition of the transition region between Kuroshio front and the Oyashio front in the east of Honshu, Japan. The possible explanations of the causes of the upwelling are as follows;In the interior of the modeled ocean the cold heavy water supplied from the north and the warm light water from the south make the north-south gradient of the pressure field and accelerate the eastward current to produce the h-orizontal divergence feld near the west coast. The divergence is compensated by the upwelling near the separation region. Another one is that the upwell-ed cold water strengthen constantly the pressure gradient which is balanced by the northward current and is weakened by the horizontal diffusion.

  • PDF

A Study on the Sea Level Variations in Korean Coastal Area (한국연안해역에서의 해면수위의 변동에 관한 연구)

  • 이경연;김동수;손창배;김창제
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.5 no.1
    • /
    • pp.19-27
    • /
    • 1999
  • This paper is to estimate the long and short term variations of mean sea level in Korean coastal waters by identifying interrelations among the mean sea level, atmospheric pressure and air temperature along the coast. For this, long-term tidal data observed at tidal and weather observation stations were brought into a statistical analysis. It was noted that, in a general sense, an inverse relationship exists between the sea level and the atmospheric pressure and a positive relationship between the sea level and air temperature, respectively. The maximum difference of monthly mean sea level was in the range of 21 to 25 cm at the eastern and southeastern coasts, meanwhile more than 30 cm being in both in southern and western coasts. It was also noted that mean sea level continues to rise in a long-term basis. Long-term variation of mean sea level trends to rise 0.10 ∼ 0.44 cm per year for each region. However, the long-term variation of mean sea level in the isolated islands shows a different trend, Ullngdo being 0.41 cm fall per year and Chejudo being 0.44 cm rise per year.

  • PDF