• Title/Summary/Keyword: sea area environment

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PERFORMANCE OF COMS SNOW AND SEA ICE DETECTION ALGORITHM

  • Lee, Jung-Rim;Chung, Chu-Yong;Ahn, Myoung-Hwan;Ou, Mi-Lim
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.278-281
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    • 2007
  • The purpose of this study is to develop snow and sea ice detection algorithm in Communication, Ocean and Meteorological Satellite (COMS) meteorological data processing system. Since COMS has only five channels, it is not affordable to use microwave or shortwave infrared data which are effective and generally used for snow detection. In order to estimate snow and sea ice coverage, combinations between available channel data(mostly visible and 3.7 ${\mu}m$) are applied to the algorithm based on threshold method. As a result, the COMS snow and sea ice detection algorithm shows reliable performance compared to MODIS products with channel limitation. Specifically, there is partial underestimation over the complicated vegetation area and overestimation over the area of high level clouds such as cirrus. Some corrections are performed by using water vapor and infrared channels to remove cloud contamination and by applying NDVI to detect more snow pixels for the underestimated area.

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Age and growth of the black rockfish, Sebastes inermis, in the Jeonnam marine ranching area in the southern Sea of Korea (한국 남해 전남바다목장해역 볼락, Sebastes inermis의 연령과 성장)

  • Kim, Hee-Yong;Kim, Sang-Hwa;Huh, Sun-Jung;Seo, Young-Il;Lee, Sun-Gil;Ko, Jun-Chul;Cha, Hyung-Kee;Choi, Mun-Sung
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.346-357
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    • 2010
  • Characteristics of age and growth of the black rockfish, Sebastes inermis sampled in the Jeonnam Marine Ranching Area (JMRA) around Geumo Islands south of Yeosu were investigated using 642 otoliths from March 2009 to February 2010. The opaque zone was formed in September once a year and hence it was used as an annulus. The parturient period was December to January, and therefore the duration from fertilization to the complete formation of the opaque zone was nineteen months. From the parameters calculated using the average length when the year ring was formed, growth of S. inermis were expressed by von Bertalanffy growth equation as $L_t$=23.267 ($1-e^{-0.4406(t+1.1971)}$) for females and $L_t$=22.030 ($1-e^{-0.5312(t+0.6834)}$) for males when is total length in age t. Through the growth equations, the maximum length was determined as 23.27cm for females and 22.03cm for males and the growth factor as 0.4406/yr and 0.5312/yr, respectively. Finally, the growth of female S. inermis is larger than the one of male S. inermis.

Spatial and Temporal Distribution of Organophosphorus Pesticides in Seawater from Saemangeum Area (새만금 해양환경에서 해수 중 유기인계 농약의 시공간적 분포)

  • Li, Dong-Hao;Hong, Sang-Hee;Shim, Won-Joon;Park, Jun-Kun;Kim, Eun-Soo
    • Ocean and Polar Research
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    • v.28 no.3
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    • pp.331-337
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    • 2006
  • Organophosphorus pesticides (OPs) were analyzed in surface water samples from the Saemangeum environment. IBP was the most abundant among 10 OPs analyzed, and accounted fur over 95% of total amount of OPs. Concentrations of IBP measured in Mangyeong River water and surface seawater ranged from 670 to 1100ng/l and from 45 to 1000 ng/l, respectively. In general, a decreasing trend of OP concentrations towards open sea was observed. The concentrations of IBP and salinity demonstrated a strong correlation $(r^2=0.96)$. This indicates that IBP showed conservative behavior in the study area, and seawater dilution is a major factor affecting distribution and variation of OPs in the Sammgem environment.

The Marine Environment and Dinoflagellates Cysts in the Southwestern Sea of Korea (한국남서해역의 해양환경과 와편모조류 시스트 분포 특성)

  • Park, Jong-Sick;Yoon, Yang-Ho;Noh, Il-Hyeon;Soh, Ho-Young;Shin, Hyeon-Ho
    • ALGAE
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    • v.23 no.2
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    • pp.135-140
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    • 2008
  • A field survey for dinoflagellate cysts was carried out from May 2000 to November 2002 for the Southwest Sea of Korea. A total dinoflagellate cysts identified were 33 species, which belonged to 17 genera, 31 species, and 2 unidentified species. A cysts density were 16-1,501 cysts-gdry$^{-1}$. The dominant species of dinoflagellate cysts in the Southwestern Sea of Korea were Spiniferites bulloideus and Scrippsiella trochoidea, which are autotrophic species. To investigate the environmental characteristics of the Southwestern Sea of Korea using the dinoflagellate cysts, a principal component analysis (PCA) was conducted using the data collected from a total of 51 stations. From the score distribution map by the PCA, the Southwestern Sea of Korea was largely divided into three regions according to the first primary component and the second primary component. In other words, Group 1 was the western sea area of Mokpo and Jindo, Group 2 was the outer sea area of the South Sea, and Group 3 was the coastal areas of the South Sea around the Archipelago. It was found that this division of sea area was influenced by effects of the sea environment of the coastal areas of Korea. The coastal areas of Mokpo and Jindo that belong to Group 1 were affected by the cold Yellow Sea water. The outer sea area of the central parts of the South Sea that belong to Group 2, which is the boundary between the Southern coastal water of Korea and the Tsushima warm water, was subject to the formation of temperature fronts throughout the year, while Group 3 was affected by the coastal waters of Korea. It was also found that this division was in close relationship with the distribution of sediment facies in the bottom layer. From the above results, the environmental factors that influence the cyst distribution in he Southwestern Sea of Korea were found to include the eutrophication status of the sea area, the physical characteristics of the sea environment such as the flow of sea current and fronts, the sediment facies in the bottom layer, and the appearance volume of motile cells.

Pollution of Polycyclic Aromatic Hydrocarbons (PAHs) in Seawater and Marine Sediments from Anmyundo Coastal Area after Oil Spill (유류사고 이후 안면도 연안 해수 및 퇴적물의 다환방향족탄화수소(PAHs) 오염에 관한 연구)

  • Lee, Wan-Seok;Park, Seung-Yoon;Kim, Pyoung-Joong;Jeon, Sang-Baeck;An, Kyoung-Ho;Choi, Yong-Seok
    • Journal of Environmental Science International
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    • v.19 no.12
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    • pp.1421-1430
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    • 2010
  • Polycyclic aromatic hydrocarbons (PAHs) were investigated in seawater and marine sediment from Anmyundo coastal area after oil spill. The concentrations of total PAHs in surface and bottom of seawater at August were 31.1 to 142.6 ng/L and 5.9 to 50.9 ng/L in August and November, respectively. The concentrations of PAHs in sediment were 21.0 to 102.9 ng/g D.W. and 32.3 to 57.4 ng/g D.W. in August and November, respectively. PAHs concentrations in seawater and sediment in August were higher than those in November about 2.5 and 1.4 times, respectively. Diagnostic ratio (PhA/AnT and FluA/Pyr) were investigated to identify source of PAHs in seawater and sediment. The PAHs in seawater originated from pyrolytic source and those in sediment originated from pyrolytic and petrogenic source. The glass, wood and coal origin was higher than petroleum origin on the combustion origin of PAHs in seawater and sediment. The seawater of Anmyundo costal area recovered from oil spill, but the sediments of that were weakly influenced by oil spill until now. Because this area is developed many fishing grounds, demanded Long Term Environmental Monitoring Program (LTEMP). The concentrations of PAHs on depth of sediments were investigated at station 8 and 10. The concentrations of PAHs were decreased with increasing depth.

A Study on Modification of Geographical Features Affecting Onset of Sea Breeze (지형적 특징이 해풍시작에 미치는 영향에 대한 연구)

  • 정우식;이화운
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.6
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    • pp.757-772
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    • 2003
  • We simulate the geographical effects on the onset time of sea breeze at Suyoung and Haeundae districts by using the LCM (Local Circulation Model). The following can be found out from the numerical simulation on Case I (real terrain) which considered the real geography of Busan metropolitan area. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. To find out more about the effects of terrain and geography on the onset time of sea breeze, the results of numerical simulation of virtual geography are as follows. In Case II (flat terrain), to find out how the terrain slope affects the onset of sea breeze, flat land and the ocean was considered. As a result, convergence of nighttime air mass at a Suyoung area and nighttime strong wind speed phenomenon was not shown. In Case III (modified flat terrain), to find out the effects of the irregularity of coastline affecting the onset of sea breeze, numerical simulation was carried out by simplifying the complex coastline into segments of straight coastline. So land breeze system and changing process of sea breeze after sunrise at Suyoung and Haeundae was simulated almost in a similar manner. Through this we could find the effects of coastal irregularities on onset of sea breeze.

A Study on Chemical Composition of Dustfall Sampled in Cheju Area: 2. Identification of Source (제주지역 강하먼지의 조성에 관하여 : 2. 오염원 추정)

  • 이기호;허철구
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.2
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    • pp.101-111
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    • 1999
  • In previous study, the local trends in dustfall chemistry and deposition were determined and the characteristics of chemical compositions among dustfall, TSP and rainwater were also compared. Based on the previous results, in this study, the effects of sea salts and soil and soil on the chemical composition of dustfall were studied and then the sources of dustfall in Cheju area were tentatively identified by principal component analysis(PCA)

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Numerical Simulation of Advection and Diffusion using the Local Wind Model in Kwangyang Bay, Korea (국지풍모델을 이용한 광양만권의 이류확산 수치모의)

  • ;;Akira Kondo
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.1
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    • pp.1-10
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    • 2002
  • A three-dimensional numerical model which involved the nesting method was developed to reproduce the wind circulation of Kwangyang Bay area which comprises complicated mountains and sea topograph. The calculated results indicated geographical effects of Kwangyang Bay area, sea/land breezes and mount-valley wind which are local circular winds. We also noticed that the northern inland area of Kwangyang Bay formed the very complex wind systems under the influence of such geographic effects when a land breeze was not formed. A good agreement was found between predicted and observed values of temperature. In addition, the calculated results of the wind direction and the wind velocity are in accord with the observed values. They showed only a slight difference in between predicted and the observed values, when the sea breeze and the land breeze are changing.

Analysis on the Effect of Meteorological Factors related to Difference of Ozone Concentration at the Neighboring Areas in Gijang Busan (인접지역간 오존 농도 차이에 대한 기상요소의 영향분석(부산광역시 기장군을 대상으로))

  • Kim, Min-Kyoung;Lee, Hwa-Woon;Jung, Woo-Sik;Do, Woo-Gon
    • Journal of Environmental Science International
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    • v.21 no.9
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    • pp.1097-1113
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    • 2012
  • Ozone is the secondary photochemical pollutant formed from ozone precursor such as nitrogen dioxide and non-methane volatile organic compounds(VOCs). The ambient concentration of ozone depends on several factors: sunshine intensity, atmospheric convection, the height of the thermal inversion layer, concentrations of nitrogen oxides and VOCs. Busan is located in the southeast coastal area of Korea so the ozone concentration of Busan is mainly affected from the meteorological variables related to the sea such as sea breeze. In this study the ozone concentrations of Busan in 2008~2010 were used to analyse the cause of the regional ozone difference in eastern area of Busan. The average ozone concentration of Youngsuri was highest in Busan however the average ozone concentration of Gijang was equal to the average ozone concentration of Busan in 2008~2010. The two sites are located in eastern area of Busan but the distance of two sites is only 9km. To find the reason for the difference of ozone concentration between Youngsuri and Gijang, the meteorological variables in two sites were analyzed. For the analysis of meteorological variables the atmospheric numerical model WRF(Weather Research and Forecasting) was used at the day of the maximum and minimum difference in the ozone concentration at the two sites. As a result of analysis, when the boundary layer height was lower and the sea breeze was weaker in Youngsuri, the ozone concentration of Youngsuri was high. Furthermore when the sea breeze blew from the south in the eastern area of Busan, the sea breeze at Youngsuri turned into the southeast and the intensity of sea breeze was weaker because of the mountain in the southern region of Youngsuri. In that case, the difference of ozone concentration between Youngsuri and Gijang was considerable.

Evaluation of the Bacteriological Safety for the Shellfish Growing Area in Jaranman.Satyangdo Area, Korea (자란만.사량도 패류생산해역의 위생학적 안전성 평가)

  • Shim, Kil-Bo;Ha, Kwang-Soo;Yoo, Hyun-Duk;Kim, Ji-Hoe;Lee, Tae-Seek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.5
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    • pp.442-448
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    • 2009
  • Bacteriological examination of a 12,700 ha area within Jaranman Saryangdo area, located in Jaran bay and Saryangdo island, was conducted with 35 fixed (designated areas and adjacent areas) seawater sampling stations between January 2006 and December 2008. According to results, the geometric mean range and the estimated 90th percentile range of fecal coliform counts in sea water samples collected in the designated area were <1.8-2.4 and <1.8-8.6 MPN/100mL, respectively. The estimated 90th percentile range of fecal coliform counts in sea water samples collected from 6 sampling stations in the adjacent areas were 6.1-34.6 MPN/100mL. Based on these results, bacteriological water quality of the designated areas in the Jaranman. Saryangdo area meet the NSSP (National Shellfish Sanitation Program) guidelines for approved area. The bacteriological sea water quality in Jaranman.Saryangdo area has been shown to be favorable at all investigated sampling stations except for July and August which coincided with heavy rainfall. In fact, the bacteriological water quality was not affected if rainfall was less than 30 mm rainfall. However, the degree of bacteriological contamination increased rapidly and the water quality exceeded approved NSSP guidelines set for rainfall above 60 mm.