• Title/Summary/Keyword: Rising Time

Search Result 982, Processing Time 0.034 seconds

Magmatic Evolutions based on Compositional Variations with Time in the Maljandeung Tuff, Ulleung Island, Korea (울릉도 말잔등응회암에서 시간에 따른 조성변화에 근거한 마그마 진화)

  • Hwang, Sang Koo;Lee, So-Jin;Ahn, Ung San
    • The Journal of the Petrological Society of Korea
    • /
    • v.28 no.2
    • /
    • pp.111-128
    • /
    • 2019
  • Ulleung Island is the top of an intraplate alkalic volcano rising 3200 m from sea floor in the East Sea (or Sea of Japan). The emergent 984.6 m consist of eruptive products of basaltic, trachytic and phonolitic magmas, which are divided into Dodong Basaltic Rocks, and Ulleung, Seonginbong and Nari groups. The Maljandeung Tuff in the Nari Group consists of thick pyroclastic sequences which are subdivided into 4 members (N-5, U-4, 3, 2), generating from explosive eruptions during past 18.8~5.6 ka B.P. From chemical data, the Member N-5, phonolitic in composition, is considerably enriched in incompatible elements and REE patterns with significant negative Eu anomalies. The members 4, 3 and 2 are phonolitic to tephriphonolitic in composition, and their REE patterns do not have significant Eu anomalies. In variation trend diagrams, many elements show abrupt compositional gaps between members, and gradual upward-mafic variations from phonolite to tephriphonolite within each member. It suggests a downward-mafic zonation that were evolved into phonolitic zone in the lower part to tephriphonolitic zone in upper part of magma chamber. It is supposed that the chemical stratification generated from multiple mechanisms of thermal gravidiffusion, crystal fractionation, and gradual melting and sequential emplacement. The stratified magmas were explosively erupted to generate a small caldera during short period (11 ka B.P.). Especially both members (U-3, 2) were accumulated by gradually erupting from the upper phonoltic zone to the lower tephriphonoltic zone of the stratified chamber in 8.4 ka B.P. and 5.6 ka B.P. time, respectively.

Analysis of the operation status and opinion on the improvement of fishing vessel structure in coastal improved stow net fishery by the questionnaire survey (설문조사를 통한 연안개량안강망어업의 조업 실태 및 어선 구조 개선에 관한 의견 분석)

  • CHANG, Ho-Young;KIM, Min-Son;HWANG, Bo-Kyu;OH, Jong Chul
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.57 no.4
    • /
    • pp.316-333
    • /
    • 2021
  • In order to understand basic data for improving the fishing system and fishing vessel structure in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 to analyze opinions on the improvement of operation status and fishing vessel structure. The questionnaire survey consisted of ten questions on the operation status of coastal improved stow net fishery and six questions on the improvement of fishing vessel structure, and the results of each question were analyzed by the region, the captain's age, the captain's career and the age of fishing vessel. As a result of analyzing opinions on the operation status of the coastal improved stow net fishery, it was found that the average time required for casting net was 32.8 to 33.0 minutes and that the average time required for hauling net was 41.0 to 42.2 minutes which took 10 to 12 minutes more than for casting net. The most important work requiring improvement during fishing operation (the first priority) were 'hauling net operation,' 'readjustment and storage of fishing gear,' and 'fish handling' and the hardest factor in fishing management were in the order of 'reduction of catch,' 'labor shortage' and 'rising labor costs.' The most institutional improvement that is most needed in coastal improved stow net fishery was an 'using fine mesh nets.' Most of the respondent to the questions on the experience in hiring foreign crews was 'either hiring or willing to hire foreign crews,' and the average number of foreign crews employed was found to be 2.3 to 2.4 persons. The most important reason for hiring (or considering employment) foreign crews was 'high labor costs.' The degree of communication with foreign crews during fishing operation were 'moderate' or 'difficult to direct work.' The most important problem in hiring foreign crews (the first priority) was an 'illegal departure.' As the survey results on the opinion of structural improvement of coastal improved stow net fishing vessel, the degree of satisfaction with fishing vessel structure related to fishing operation was found to be somewhat unsatisfactory, with an average of 3.3 points on a five-point scale. The inconvenient structure of fishing vessel in possession (the first priority), the space needed most for the construction of new fishing vessel (the first priority) and the space considered important for the construction of new fishing vessel (the first prioprity) was a 'fish warehouse.' The most preferred equipment for the construction of new fishing vessel were 'engine operation monitoring' and 'navigation safety devices.' The average size (tonnage class), the average horse power and the average total length of fishing vessel for proper profit and safety fishing operation was between 13.8 and 14.0 tonnes, 808.3 to 819.5 H.P. and 23.4 to 23.5 meters, respectively. The results of the operation status of coastal improved stow net fishery and the requirement for improving the fishing vessel structure are expected to be provided as basic data for reference when we build or improve the fishing vessel.

Size-dependent Transcriptional Modulation of Genes Involved in Cytochrome P450 Family in the Brackish Water Flea Diaphanosoma celebensis Exposed to Polystyrene Beads (기수산물벼룩 Diaphanosoma celebensis의 미세플라스틱 노출에 따른 크기 의존적 Cytochrome P450 유전자의 발현 양상)

  • Min Jeong Jeon;Je-Won Yoo;Young-Mi Lee
    • Journal of Marine Life Science
    • /
    • v.8 no.2
    • /
    • pp.104-114
    • /
    • 2023
  • As plastic usage increases globally, the amount of plastic waste entering the marine environment is steadily rising. Microplastics, in particular, can be ingested by marine organisms and accumulated in their digestive tracts, causing harmful effects on their growth and reproduction. Cytochrome P450 (CYP) enzymes are known to metabolize various environmental pollutants as detoxification enzymes, but their role in crustaceans is not well understood. In this study, sequences of nine CYP genes (CYP370A4, CYP370C5 from clan 2; CYP350A1, CYP350C5, CYP361A1 from clan 3; CYP4AN-like, CYP4AP2, CYP4AP3, CYP4C33-like1 from clan 4) were analyzed using conserved domains in the brackish water flea Diaphanosoma celebensis. Additionally, after exposure to three different sizes of polystyrene beads (0.05-, 0.5-, 6-㎛ PS beads; 0.1, 1, and 10 mg/L) for 48 hours, the expression of these nine CYP genes were investigated using real-time reverse transcription polymerase chain reaction (RT-PCR). The results showed that all CYP genes possessed conserved motifs, indicating that D. celebensis CYP has evolutionarily conserved functions. Among these CYP genes, the expression of CYP370C5, CYP360A1, and CYP4C122 showed a significant increase after exposure to 0.05-㎛ PS beads, suggesting their involvement in PS metabolism. This research will contribute to understanding the molecular mode of actions of microplastics on marine invertebrates.

A Study on Dietary Habits and Nutrient Intakes by Skipping Meals of Elementary School Children in Incheon (인천 지역 초등학생의 결식에 따른 식습관과 영양 섭취 상태에 관한 연구)

  • Park, Sook-Kyoung;Kim, Myung-Hee;Choi, Mi-Kyeong
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.20 no.5
    • /
    • pp.668-679
    • /
    • 2010
  • The purpose of this study was to analyze the relations of children's skipping meals after researching eating habits and lifestyle, parents' appreciation in nutrition behavior and dietary intake, throughout the research based on 4th to 6th grade students, total of 362 children at an elementary school in Inchoen. There were 104 students in skipping meals group and 258 students in eating meals group, with the average ages of 10.9, and 10.8, respectively. The average height and weight were 144.5 cm, 38.6 kg for skipping meals group, and 145.7 cm, 39.3 kg for eating meals group. Parents' appreciation of importance in breakfast showed a significant difference in whether children skip the meals or not (p<0.01). 43.7% of parents in skipping meals group answered that they serve breakfast everyday, compared to eating meals group with the percentage of 94.9%, showing significant difference in frequency of serving breakfast for their children (p<0.001). The skipping meals group answered that the reason they do not have breakfast is because they do not have time, which showed the highest percentage of 41.2%. For the eating meals group, 40.5% of students answered that they do not have appetite, which also showed difference (p<0.001). The skipping meals group tended to wake up later than those who have breakfast in the morning(p<0.01). The breakfast time for skipping meals group was later than the eating meals group, and according to whether they have breakfast of not, it showed a difference as well(p<0.01). Total score of nutrition attitude in skipping meals group and eating meals group were 30.8 and 32.1, showing that eating meals group showed more good in nutrition attitude (p<0.05). Daily intakes of energy (p<0.01) and protein (p<0.01) in skipping meals group were significantly lower than those in eating meals group. Skipping meals group bad lower rates in INQs of protein (p<0.01) and zinc (p<0.01), showing that skipping meals group is having low quality meals in nutrition. In conclusion, this study revealed that students with skipping meals are more likely to have meals that lacks nutrition or have low quality meals, and the time of rising hour in the morning, frequency of eating snacks can also affect whether or not they skip meals.

A Study on the Excavated Sab(a funeral fan) from Lime-filled Tomb and Lime-layered Tomb during the Joseon Dynasty (조선시대 회격·회곽묘 출토 삽(翣)에 대한 고찰)

  • Yi, Seung Hae;An, Bo Yeon
    • Korean Journal of Heritage: History & Science
    • /
    • v.41 no.2
    • /
    • pp.43-59
    • /
    • 2008
  • Sap(?, a funeral fan) is a funeral ceremonial object used in association with a Confucian ceremonial custom, which was crafted by making a wooden frame, attaching a white cloth or a thick paper onto it, drawing pictures on it, and making a holder for a handle. According to Liji(Records of Rites), Sap was used since the Zhou Dynasty, and these Chinese Sap examples are no big different than the Korean Sap examples, which were described in Joseon Wangjo Sillok(Annals of the Joseon Dynasty), Gukjo Oryeui(the Five Rites of the State), and Sarye Pyeollam(Handbook on Four Rituals). This study explored Sap excavated in lime-filled tombs and lime-layered tombs of aristocrats dating back to Joseon, as well as their historical records to examine Sap's characteristics according to their examples, manufacturing methods, and use time. The number and designs of Sap varied according to the deceased' social status aristocrats used mainly one pair of 亞-shaped Bulsap, and a pair of Hwasap with a cloud design depicted on it. A Sap was wrapped twice with Chojuji paper or Jeojuji paper, and for the third time with Yeonchangji paper. Then, it was covered with a white ramie, a hemp, a cotton, a silk satin, etc. Bobul(an axe shape and 亞-shape design) was drawn on both sides of Sap, and a rising current of cloud was drawn at the peripheral area mainly with red or scarlet pigments. Sap, which were excavated from aristocrats'lime-filled and lime-layered tombs, are the type of Sap which were separated from its handle. These excavated Sap are those whose long handles were burnt during the death carriage procession, leaving Sap, which later were erected on both sides of the coffin. The manufacturing process of excavated relics can be inferred by examining them. The excavated relics are classified into those with three points and those with two points according to the number of point. Of the three-point type(Type I), there is the kind of relic that was woven into something like a basket by using a whole wood plate or cutting bamboo into flat shapes. The three-point Sap was concentrated comparatively in the early half of Joseon, and was manufactured with various methods compared with its rather unified overall shape. In the meantime, the two-point Sap was manufactured with a relatively formatted method; its body was manufactured in the form of a rectangle or a reverse trapezoid, and then its upper parts with two points hanging from them were connected, and the top surface was made into a curve(Type II) or a straight line(Type III) differentiating it from the three-point type. This manufacturing method, compared with that of the three-point type, is simple, but is not greatly different from the three-point type manufacturing method. In particular, the method of crafting the top surface into a straight line has been used until today. Of the examined 30 Sap examples, those whose production years were made known from the buried persons'death years inscribed on the tomb stones, were reexamined, indicating that type I was concentrated in the first half of the $16^{th}$ century. Type II spanned from the second half of the $16^{th}$ century to the second half of the $17^{th}$ century, and type III spanned from the first half of the $17^{th}$ century to the first half of the $18^{th}$ century. The shape of Sap is deemed to have changed from type I to type II and again from type II to type III In the $17^{th}$ century, which was a time of change, types II and III coexisted. Of the three types of Sap, types II and III re similar because they have two points; thus a noteworthy transit time is thought to have been the middle of the $16^{th}$ century. Type I compared with types II and III is thought to have required more efforts and skills in the production process, and as time passed, the shape and manufacturing methods of Sap are presumed to have been further simplified according to the principle of economy. The simplification of funeral ceremonies is presumed to have been furthered after Imjinwaeran(Japanese invasion of Joseon, 1592~1598), given that as shown in the Annals of King Seonjo, state funerals were suspended several times. In the case of Sap, simplification began from the second half of the $16^{th}$ century, and even in the $18^{th}$ century, rather than separately crafting Sap, Sap was directly drawn on the coffin cover and the coffin. However, in this simplification of form, regulations on the use of Sap specified in Liji were observed, and thus the ceremony was rationally simplified.

A Study on the Effect of Outsourced to Management Performance (아웃소싱이 기업성과에 미치는 영향)

  • Bae, Ha Jin;Kwak, Soon Jin;Kim, Kwang Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.9 no.5
    • /
    • pp.83-94
    • /
    • 2014
  • Before economical crisis in 1997, domestic company focused on increasing the size of outward experience which including organization. The result of increasing outward experience without substance was economical crisis, so after that time, many companies have been changing their focus from insourcing to strengthen the core competence to secure global market. This is becoming a cause of following that companies are reducing their outward experience. Especially, to process tasks more effectively and to cope with rapid change of business environment, such as incoming raw material from overseas/high raising of salary/rising property prices, many companies decided outsourcing method. At most of hypothesis, the result was that outsourcing can affect positively to the business. First, introducing of outsourcing during focusing on core competence can be positive effect for company performance such as business management /productivity /procurement /administration /product competitiveness /technology. Second, the result that analyzed based on a point of view of population statics after outsourcing was positive effect at the most of research. Third, result of effectiveness for every outsourcing type classified by 4M was also can be positive at the most of research. Fourth, the characteristic of population statics can be positive effect at the most of category when select outsourcing companies. Research result of outsourcing was various based on the goal of outsourcing. It is revealed by investigation of domestic/overseas treatise that there are opposite two opinions. In this research, there is no consistent result that the outsourcing can give effects on business performance, but most of hypothesis indicates that outsourcing can give positive effect on the business performance.In this research, based on the outsourcing intensity, mutual relation was analyzed. The assumption of the reason of outsourcing is economical and organizational. First, sampling numbers of research was too small so it is too difficult to get significant business performance result. (Sampling : 150, Replied : 106, Rate of Reply : 71%) Second, tried to compare significant differences of outsourcing methods which were divided based on 4M, but the there is gaps between the number of Cell and too difficult to make replier understand. Third, it is tried to find the degrees of effect that the point of view of popular statics can effect on business performances and selection of outsourced companies.

  • PDF

A Field Survey and Analysis of Ground Water Level and Soil Moisture in A Riparian Vegetation Zone (식생사주 역에서 지하수위와 토양수분의 현장 조사·분석)

  • Woo, Hyo-Seop;Chung, Sang-Joon;Cho, Hyung-Jin
    • Journal of Korea Water Resources Association
    • /
    • v.44 no.10
    • /
    • pp.797-807
    • /
    • 2011
  • Phenomenon of vegetation recruitment on the sand bar is drastically rising in the streams and rivers in Korea. In the 1960s prior to industrialization and urbanization, most of the streams were consisted of sands and gravels, what we call, 'White River'. Owing to dam construction, stream maintenance, etc. carried out since the '70s, the characteristic of flow duration and sediment transport have been disturbed resulting in the abundance of vegetation in the waterfront, that is, 'Green River' is under progress. This study purposed to identify the correlation among water level, water temperature, rainfall, soil moisture and soil texture out of the factors which give an effect on the vegetation recruitment on the sand bar of unregulated stream. To this purpose, this study selected the downstream of Naeseong Stream, one of sand rivers in Korea, as the river section for test and conducted the monitoring and analysis for 289 days. In addition, this study analyzed the aerial photos taken from 1970 to 2009 in order to identify the aged change in vegetation from the past to the present. The range of the tested river section was 361 m in transverse length and about 2 km in longitudinal length. According to the survey analysis, the tested river section in Naeseong Stream was a gaining river showing the higher underground-water level by 20~30 m compared to Stream water level. The difference in the underground water temperature was less than $5^{\circ}C$ by day and season and the Stream temperature did not fall to $10^{\circ}C$ and less from May when the vegetation germination begins in earnest. The impact factor on soil moisture was the underground water level in the lower layer and the rainfall in the upper layer and it was found that all the upper and lower layer were influenced by soil particle size. The soil from surface to 1 m-underground out of 6 soil moisture-measured points was sand with the $D_{50}$ size of 0.07~1.37 mm and it's assumed that the capillary height possible in the particle size would reach around 14~43 cm. On the other hand, according to the result of space analysis on the tested river section of unregulated stream for 40 years, it was found that the artificial disturbance and drought promoted the vegetation recruitment and the flooding resulted in the frequency extinction of vegetation communities. Even though the small and large scales of recruitment and extinction in vegetation have been repeated since 1970, the present vegetation area increased clearly compared to the past. It's found that the vegetation area is gradually increasing over time.

Enzyme Linked Immunosorbent Assay for the Detection of Antibody to Avian Infectious Bronchitis Virus (효소면역법에 의한 닭 전염성 기관지염 바이러스 항체검사)

  • 송현제;최정옥
    • Korean Journal of Poultry Science
    • /
    • v.18 no.3
    • /
    • pp.183-196
    • /
    • 1991
  • In order to establish ELISA method to detect antibody against IBV various factors involved were examined. Antigen was prepared from Massachusetts type IBV which is known to be one of serotypes distributed most widely. The virus was grown in embryonated SPF chicken eggs. Allantoic fluid harvested was processed to ultracentrifugation and sucrose density gradient centrifugation to produce a purified antigen The antisera selected from the field samples based on hemagglutination inhibition test were used as the standard positive and negative sera for this study and the results obtained were summarized as follows. 1 , It was found that ELISA test was satisfactory when the purified antigen was coated on the plate in the amount of about 40ng protein per well. In case of the phospholipase treated hemagglutinating antigen it gave satisfactory results when the each well wns coated with 1.2 to 2.5 hemagglutinating unit which was equivalent to 40 to 90ng of protein. 2. There was no significant difference in the ratio of optical density of positive to that of negative serum whether the coated antigen was held for 1 hour at 37$^{\circ}C$ or it was held overnight at 4$^{\circ}C$. The coated antigen could be kept in dried state without change of antigenecity for at least one month of experimental period at 4$^{\circ}C$. 3. There was a big variation in the optical density and P/N values depending on the maker of the plates and on the plate of the same maker. 4. It was found that background optical density was negligible when serum was diluted more than 1:50 and serum dilution of 1:100 appeared to be appropriate as a routine test dilution to screen the antibody. 5. Optical density was fairly constant 15 minutes afterward from the time substrate was treated and during the 4 hours after stopper was treated. 6. There was a low correlation(r=0.42) between ELISA and HI test. However, when 74serum samples were tested for the IBV antibody, 98.7% were found to be positive by both tests in which titers of 2$^{6}$ or more by HI test and P/N values of 1.4 or more by ELISA were considered to be positive, 7 Day-old IBV vaccinated chickens shows a similar antibody decay and rising pattern until 8 weeks of age by the two tests, ELISA and HI.

  • PDF

An Analysis of Determinants of Smoking and Drinking of Community people in Rural area (농촌주민의 흡연 및 음주 실태와 이에 영향을 미치는 요인분석)

  • 남철현
    • Korean Journal of Health Education and Promotion
    • /
    • v.6 no.1
    • /
    • pp.48-59
    • /
    • 1989
  • The study was designed. to analyse the factors effecting to smoking and drinking of community people in rural area. The study has been surveyed through interviews by trained college students for 1,846 residents who live in rural area(Eup or Myun office is located)for 20days(from 3rd. to 22M. in August, 1988) The summary and conclusions are as follows. 1. The number of answers on the questionaires was 1846. And the percent of man was 55.7 %(woman 44.3 %). Among age group 20-29 years group with 30.4 % was larger than any other group. Anaverage age of answers was 38.6 years. 2.In the period of residence, 21.5 % of the residents lived within 5 years(This group was larger than any other group). In occupations, workers in agriculture and fishing was more than other job occupants. In education, the percent of high school graduates was 44.0 %(higher than any other group) 3.The smoking rate of rural residents was 41.8 %and man's smoking rate was 76.0 % (woman's smoking rate was 7.6 %). These rates were higher than the rates in 1985 (The smoking rate of nation was 32.0 %). First of all, woman's smoking rate increased rapidly 4.As for smoking amount, in male 52.8% of smokers smoked a cigarette case (20 cigarettes) in a day, and 16.9 % of smokers smoked more than one cigarette case. In female 42.5 % of woman smokers smoked a half case in a day and the rate of non-smokers diminished to 77.8 % 5.The rate of non-smokers in 21-29 years group was higher than any other group and a smoking rate increased as an age increased. However, a smoking amount decreased as an age increased. This suggests that people are more concerning about their health as their ages increase.. 6.The smoking rate of college graduates was 58.8 %(higher than any other group) and in a smoking amount 36.4 % of college graduates, 29.8 % of high school graduates smoked more than a cigarette case in a day. This shows that people in a higher education group smoke more than those in other groups. 7.As for non-smoking rate, students, service job workers, company employees, and teachers was 54.1%, 43.4%. 40.1% and 39.5%. respectively. As for smoking rate, workers in agriculture and fishing was the highest level of all job employees. Public officers smoked less than the workers in agriculture and the smoking rate of teachers was less than that of public officers. with regard to smoking amount. above one cigarette case in a day was 39.9 % in public officers, 39.2 % workers in agriculture and fishing, 37.9 % in businessmen, 34.2 % in teachers, 31.9 % in service job employees and 31.6 % in a company employees. 8.The variables which had an effect on smoking were sex (B=.1701), job(B=.1688), education(B=.1671), age(B=.1125). These variables were significant in P<0.05 statistically. Explanatory variance level was 19% 9.The drinking rate of community residents was 61.8% and man's drinking rate was 81.7%(woman's drinking rate was 38.9%). As drinking rate 18.0%(the highest rate) of man drinkers drank 3 bottles of beer in a general drinking and 12.1% of them drank more than 10 bottles. 12.1% (the highest rate)of woman drinkers drank 2 cups of beer. The rising rate of woman's drinking of alcohol was remarkable. 10.Each non-drinking rate of age groups was 27.6% (in 20-30 years group), 28.0% (in 30-39 years group), 28.9%(in 40-49 years group) and 32,6%(in 50-59 years group), 10,7%(the highest rate) of 20-29 and 30-39 years groups drank above 3 bottles. 7.5% of 20-29 years group and 7.7% of 30-39 years group drank above 10 bottles. In 40-49 years group, 14.4 % of them drank a bottle and 8.1% of them drank above 10 bottles. In 50-59years group, 14,2% of them drank 2 bottles and 5.3 % of them drank above 10 bottles. This shows that a drinking rate decresed as an age increased. 11.Non-drinking rate was higher as an education level was lower. Each non-drinking rate of non-educated group, elementary school group, middle school group and high school group was 41.0 % of high school graduates and 14.5 % of college graduates drank 3 bottles of beer. 9.7 %(the highest rate) of college graduates drank above 10 bottles, in general drinking. 12.Each non-drinking rate of businessmen, farmers, service job workers, and students was 31.3%, 28.2%, 26.8% and 25.9%. However, Each drinking rate of public officers, company employees and teachers was 73.3 %, 72.2 % and 68.4 %. This tells us that the drinking rate of mental workers is higher than that of physical workers. 14.9 % of farmers and 14.4 % of public officers drank 3 bottles at a time. 10.5 % of teachers and 9.9 % of public officers drank above 10 bottles. 13.The variables which affect on drinking were sex(B=.1545), education(B=.1476), job(B=.1064), and age(B=.1052). These variables were significant in the level of 0.05 % and explanatory variance level was 18 %. 14.Government have to educate people and demonstrate the health hazards caused by smoking and over-drinking. Especially, No-smoking campaign for woman and education not to over drink for professional job workers are necessary.

  • PDF

High-Resolution Numerical Simulations with WRF/Noah-MP in Cheongmicheon Farmland in Korea During the 2014 Special Observation Period (2014년 특별관측 기간 동안 청미천 농경지에서의 WRF/Noah-MP 고해상도 수치모의)

  • Song, Jiae;Lee, Seung-Jae;Kang, Minseok;Moon, Minkyu;Lee, Jung-Hoon;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.17 no.4
    • /
    • pp.384-398
    • /
    • 2015
  • In this paper, the high-resolution Weather Research and Forecasting/Noah-MultiParameterization (WRF/Noah-MP) modeling system is configured for the Cheongmicheon Farmland site in Korea (CFK), and its performance in land and atmospheric simulation is evaluated using the observed data at CFK during the 2014 special observation period (21 August-10 September). In order to explore the usefulness of turning on Noah-MP dynamic vegetation in midterm simulations of surface and atmospheric variables, two numerical experiments are conducted without dynamic vegetation and with dynamic vegetation (referred to as CTL and DVG experiments, respectively). The main results are as following. 1) CTL showed a tendency of overestimating daytime net shortwave radiation, thereby surface heat fluxes and Bowen ratio. The CTL experiment showed reasonable magnitudes and timing of air temperature at 2 m and 10 m; especially the small error in simulating minimum air temperature showed high potential for predicting frost and leaf wetness duration. The CTL experiment overestimated 10-m wind and precipitation, but the beginning and ending time of precipitation were well captured. 2) When the dynamic vegetation was turned on, the WRF/Noah-MP system showed more realistic values of leaf area index (LAI), net shortwave radiation, surface heat fluxes, Bowen ratio, air temperature, wind and precipitation. The DVG experiment, where LAI is a prognostic variable, produced larger LAI than CTL, and the larger LAI showed better agreement with the observed. The simulated Bowen ratio got closer to the observed ratio, indicating reasonable surface energy partition. The DVG experiment showed patterns similar to CTL, with differences for maximum air temperature. Both experiments showed faster rising of 10-m air temperature during the morning growth hours, presumably due to the rapid growth of daytime mixed layers in the Yonsei University (YSU) boundary layer scheme. The DVG experiment decreased errors in simulating 10-m wind and precipitation. 3) As horizontal resolution increases, the models did not show practical improvement in simulation performance for surface fluxes, air temperature, wind and precipitation, and required three-dimensional observation for more agricultural land spots as well as consistency in model topography and land cover data.