• 제목/요약/키워드: Circulation Pattern

검색결과 326건 처리시간 0.026초

북극 온난화에 따른 겨울철 대기 변동성 분석 연구 (Analysis on Winter Atmosphereic Variability Related to Arctic Warming)

  • 김백민;정의현;임규호;김현경
    • 대기
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    • 제24권2호
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    • pp.131-140
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    • 2014
  • The "Barents Oscillation (BO)", first designated by Paul Skeie (2000), is an anomalous recurring atmospheric circulation pattern of high relevance for the climate of the Nordic Seas and Siberia, which is defined as the second Emperical Orthogonal Function (EOF) of monthly winter sea level pressure (SLP) anomalies, where the leading EOF is the Arctic Oscillation (AO). BO, however, did not attracted much interest. In recent two decades, variability of BO tends to increase. In this study, we analyzed the spatio-temporal structures of Atmospheric internal modes such as Arctic Oscillation (AO) and Barents Oscillation (BO) and examined how these are related with Arctic warming in recent decade. We identified various aspects of BO, not dealt in Skeie (2000), such as upper-level circulation and surface characteristics for extended period including recent decade and examined link with other surface variables such as sea-ice and sea surface temperature. From the results, it was shown that the BO showed more regionally confined spatial pattern compared to AO and has intensified during recent decade. The regional dipolelar structure centered at Barents sea and Siberia was revealed in both sea-level pressure and 500 hPa geopotential height. Also, BO showed a stronger link (correlation) with sea-ice and sea surface temperature especially over Barents-Kara seas suggesting it is playing an important role for recent Arctic amplification. BO also showed high correlation with Ural Blocking Index (UBI), which measures seasonal activity of Ural blocking. Since Ural blocking is known as a major component of Eurasian winter monsoon and can be linked to extreme weathers, we suggest deeper understanding of BO can provide a missing link between recent Arctic amplification and increase in extreme weathers in midlatitude in recent decades.

여름철 북극 진동과 한반도 폭염의 관련성 (The Relationship between the Arctic Oscillation and Heatwaves on the Korean Peninsula)

  • 김정훈;노엘;김맹기
    • 한국제4기학회지
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    • 제33권1_2호
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    • pp.25-35
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    • 2021
  • In this study, we identified characteristics of heatwaves on the Korean Peninsula and related atmospheric circulation patterns using data on the daily maximum temperature (TMX) and reanalysis data for the past 42 years (1979-2020) and analyzed their connection to the Arctic oscillation (AO). The heatwave on the Korean Peninsula showed to be stronger and more frequent in the 2000s. The recent strong and frequent heatwaves on the Korean Peninsula are mainly affected by abnormal high-pressure over the Korean Peninsula on the middle/upper-level atmosphere and the strengthening of the North Pacific high pressure. Interestingly, composite difference of sea level pressure showed very similar results to the positive AO pattern. The correlation coefficients between the summertime AO and the TMX and HWD of the Korean Peninsula were 0.407 and 0.437, respectively, which showed a statistical significance in 1%, and showed a clear relationship with the abnormal high-pressure over the Korean Peninsula and the strengthening of the North Pacific high pressure. In addition, in the positive AO phase, the TMX and HWD of the Korean peninsula were approximately 30.1 ℃ and 14.6 days, which were about 1.2 ℃ and 8.8 days higher than in the negative AO phase, respectively. As a result of the 15-year moving average correlation analysis, the relationship between the heatwave and AO on the Korean Peninsula has increased significantly since 2003, and the linear relationship between them has become more apparent. Moreover, after the 2000s, when the relationship developed, AO had more strongly induced the atmospheric circulation pattern to be more favorable to the occurrence of heatwaves in the Korean Peninsula. This study implies that understanding the AO, which is the large-scale variability in the Northern Hemisphere, and the Arctic-mid latitude teleconnection, can improve the performance of global climate models and help predict the seasonality of the summer heatwave on the Korean Peninsula.

도립도서관 이용 패턴 분석을 통한 발전 방안 연구 - J 도립도서관을 중심으로 - (A Study on the Development Plan in Usage Pattern Analytics of J Provincial Library)

  • 장우권;박성우;정대근;여진원
    • 한국문헌정보학회지
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    • 제49권1호
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    • pp.173-200
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    • 2015
  • 이 연구는 J도 도립도서관의 대출과 운영현황을 조사 분석하여 향후 발전방안을 모색하는데 있다. 이를 위해 도서관 이용증 발급자 30,072명과 대출건수(2012~2013년) 705,447건을 분석하였으며, 도서관 발전계획 및 이용자 만족도를 조사하여 이를 비교분석하였다. 분석방법은 SPSS 21.0을 사용하였다. 이를 통해 도립도서관 이용자의 도서관 이용 행태 및 자료 이용 패턴 등을 확인하였으며, 분석 결과를 기반으로 도립도서관의 발전방안을 제시하였다.

하구밀도류와 바람장이 영일만 해수유동에 미치는 영향 (Numerical Prediction of Tidal Current by Effects of Wind and Density Current in Estuaries of Yeong-il Bay)

  • 윤한삼;이인철;류청로
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2003년도 추계학술대회 논문집
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    • pp.277-283
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    • 2003
  • This paper constructed the 3D real-time numerical model for which predicts the water quality and movement characteristics of the inner bay, which consider the characteristics of the wind-driven current and density current in estuaries which generated by the river discharge from the Hyeong-san river and oceanic water of the Eastern sea. The constructed numerical model reappeared successfully the seawater circulation current of Yeong-il Bay, which used the input conditions of the real-time tidal current, river discharge and weather conditions at March of 2001 year. Also to observe the wind-driven current and density current in estuaries effected to the seawater circulation pattern of the inner bay, we investigated the analyzation for the each impact factors and the relationship with the water quality of Yeong-il bay

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가금(柯琴)의 "태양병해(太陽病解)"를 통한 "상한론(傷寒論)" 태양병(太陽病)의 개념에 대한 연구(硏究) (A study on the notion of Shanghanlun Greater yang disease from Ke-qin's Taiyangbingjie)

  • 이상협
    • 대한한의학원전학회지
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    • 제25권2호
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    • pp.1-13
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    • 2012
  • Objective : Zhang, Zhongjing(張仲景)'s Sanghanlun(傷寒論) is based on Six-channels system(六經) to classified a disease. But the notion of Six-channels system seems to be a very various angles. For example, Meridian and collateral theory(經絡說), Viscera and Bowels theory(臟腑說), Grade theory(段階說), Surface theory(地面說), Symptoms theory(症候群說), Six-disease theory(六病說), Eight principle pattern theory(八綱說) and all the rest of it. Above all things Meridian and collateral theory was very frequently quoted to explain the Six-channels system(六經). But it's true notion is not restrict to a meridian vessel(經脈). Method : I will try to describe the Sanghanlun's Greater yang disease(太陽病) through the Ke-qin(柯琴)'s Taiyangbingjie(太陽病解), and I would like to point out that the existing perception that Greater yang(太陽) is connected with Bladder meridian(足太陽膀胱經) is wrong. Result : Ke-qin's Taiyangbingjie explained the greater yang disease was connected with Heart(yang within yang), which was located in the top half and the outer layer of the body. In addition to the presence of the diaphragm or lungs are involved with. Conclusion : Practical meaning of greater yang disease is not connect with Bladder meridian, but it is related to the Heart and Lung for maintain the Nutrient and defense circulation (營衛循環).

정다면체 문제 해결 과정에서 나타나는 고등학교 학생들의 심상에 관한 사례연구 (A case study on high school students' mental image in the process of solving regular polyhedron problems)

  • 홍갑룡;김원경
    • 한국수학교육학회지시리즈A:수학교육
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    • 제53권4호
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    • pp.493-507
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    • 2014
  • The purpose of this study is to analyze how high school students form and interpret the mental image in the process of solving regular polyhedron problems. For this purpose, a set of problems about the regular polyhedron's vertex is developed on the base of the regular polyhedron's duality and circulation. and applied to 2 students of the 12th graders in D high school. After 2 hours of teaching and learning and another 2 hours of mental image-analysis process, the following research findings are obtained. Fisrt, a student who recorded medium high-level grade in the national scholastic test can build the dynamic image or the patten image in the process of solving regular polyhedron's vertex problems by utilizing the 3D geometry program. However, the other student who recorded low-level grade can build the concrete-pictorial image. Second, pattern image or dynamic image can help students solve the regular polyhedron's vertex problems by proper transformation of informations and the mental images while the concrete-pictorial image does not help. Hence, it is recommended that the mathematics teachers should develop teaching and learning materials about the regular polyhedron's duality and circulation and also give students suitable questions to build the various mental images.

고해상도 해양순환모형을 이용한 씨프린스호 유류유출 사고 수치실험 (Numerical Experiment on Sea Prince Oil Spill Incident Using a High Resolution Ocean Circulation Model)

  • 김예솔;이호진;정경태;박재훈;이현정
    • Ocean and Polar Research
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    • 제34권3호
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    • pp.337-348
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    • 2012
  • This study investigates the effects of tide, wind and oceanic currents on oil spill dispersions through a series of numerical floats tracking experiments on the Sea Prince oil spill incident occurred in 1995 using a 3-dimensional high resolution ocean circulation model. For that, a total of four experimental cases (experiment with tide, wind and oceanic currents, experiment with tide and oceanic currents, experiment with wind and oceanic currents, and experiment with tide and wind) were compared. It could be seen that results from experiment involving all external forces showed better agreement with the observed pattern of oil slick movement than other cases. The oceanic currents acted to drive floats to move to the western channel of the Korea straits and wind accelerated the eastward movement of floats in the early stage of the incident. Tidal currents played significant role in the horizontal dispersion of floats.

한반도 여름 강우량의 변화에서 1996년을 중심으로 나타나는 남북진동 패턴 (The South-North Oscillation Centered on 1996 in Korean Summer Rainfall Variability)

  • 최기선;오수빈;김도우;변희룡
    • 대기
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    • 제20권2호
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    • pp.91-100
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    • 2010
  • In accordance with the time series of rainfall in summer (June, July and August) in South and North Korea for recent 28 years (1981-2008), rainfall is substantially increased in South Korea since 1996, while it is significantly decreased in North Korea. In particular, the decreasing tendency of rainfall in summer in North Korea is more definitely observed during the $2^{nd}$ rainy season (late August - mid September) in intraseasonal variation. Such a feature is also confirmed in the spatial distribution of oscillation pattern between South and North Korea on the basis of 1996 which is obtained by empirical orthogonal function analysis using the summer rainfall observed in all weather observation stations in South and North Korea. For the decreasing tendency of rainfall in North Korea, it is found that northeasterlies from anticyclonic circulation centered on around Baikal Lake weaken convective activity during summer. On the contrary, the increasing tendency of rainfall in South Korea is related to the strengthened cyclonic circulation in the southern region of China and accordingly, enhances southwesterlies in South Korea.

낙동강 하구역의 사주 퇴적특성과 물질수송플럭스 산정 (Deposition Characteristics of the Sandbar and Estimation of the Mass Transport Flux in the Nakdong Estuary)

  • 윤한삼;이인철;류청로
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.131-137
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    • 2004
  • This paper is intended as an investigation of the deposition characteristics and mass transport flux estimation in the Nakdong estuary. In order to understand the effects of the tidal current circulation which influenced to an estuary terrain change, the seawater circulation calculation by the use of 2D numerical model for the three cases of without riverflow, mean and flood riverflow quantity condition practiced and each sectional net-flux of water quantity between sandbars(so called, dung) estimated. It may be that an estuary terrain change due to the large scale construction and reclamation at the Nakdong estuary influence to the long-time deposition characteristics. by the revim for the old research, we know that the development of the local sandbars has been moved toward the east-side from the west-side estuary area after the construction of the Nakdong river dike, at present the strong-acted location is the Bakhap-dung of the front sea of Tadea. The seawater circulation pattern at this large scale area of tidal flat bring on a change due to the water quantity outflowing from the Nakdong river. Base on the calculated results for the section net-flux of water quantity, we see that the accumulating action very strong at the local sea around Jangjado, Bakhapdung and Tadae for the case of flood riverflow quantity condition, but at the local sea around Jinudo for the another cases. Consequently, it is emphasized that in the Nakdong estuary the main sensitive regions which influenced from the discharge of riverflow were the local sea around Jangjado, Bakhapdung, Tadae and Jinudo.

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고해상도 해양순환모델을 활용한 제주도 주변해역의 해수유동 특성 (Current Systems in the Adjacent Seas of Jeju Island Using a High-Resolution Regional Ocean Circulation Model)

  • 차상철;문재홍
    • Ocean and Polar Research
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    • 제42권3호
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    • pp.211-223
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    • 2020
  • With the increasing demand for improved marine environments and safety, greater ability to minimize damages to coastal areas from harmful organisms, ship accidents, oil spills, etc. is required. In this regard, an accurate assessment and understanding of current systems is a crucial step to improve forecasting ability. In this study, we examine spatial and temporal characteristics of current systems in the adjacent seas of Jeju Island using a high-resolution regional ocean circulation model. Our model successfully captures the features of tides and tidal currents observed around Jeju Island. The tide form number calculated from the model result ranges between 0.3 and 0.45 in the adjacent seas of Jeju Island, indicating that the dominant type of tides is a combination of diurnal and semidiurnal, but predominantly semidiurnal. The spatial pattern of tidal current ellipses show that the tidal currents oscillate in a northwest-southeast direction and the rotating direction is clockwise in the adjacent seas of Jeju Island and counterclockwise in the Jeju Strait. Compared to the mean kinetic energy, the contribution of tidal current energy prevails the most parts of the region, but largely decreases in the eastern seas of Jeju Island where the Tsushima Warm Current is dominant. In addition, a Lagrangian particle-tracking experiment conducted suggests that particle trajectories in tidal currents flowing along the coast may differ substantially from the mean current direction. Thus, improving our understanding of tidal currents is essential to forecast the transport of marine pollution and harmful organisms in the adjacent seas of Jeju Island.