• 제목/요약/키워드: interannual variation

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The Seasonal and Interannual Variability of the Volume Transport through the Western Channel of the Korea Strait

  • Kim, Young-Ju;Takikawa, Tetsutaro;An, Hui-Soo;Yoon, Jong-Hwan
    • Journal of the korean society of oceanography
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    • 제39권3호
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    • pp.155-162
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    • 2004
  • The variation of volume transport during the period from 1965 to 2000 through the western channel of the Korea Strait was estimated by obtaining an relation function between the ADCP volume transport and the geostrophic volume transport estimated by the sea level difference between Pusan and Izuhara. The estimated climatological mean volume transport during past 36 years has seasonal variation with a minimum of 1.15 Sv in February and a maximum of 1.88 Sv in October. The mean volume transport for 36 years is 1.51 Sv. The annual mean volume transport has an interannual variation with a minimum of 1.26 Sv in 1968 and maximum of 1.90 Sv in 1973, with three dominant periods of variations of 14.96 years, 4.96 years and 2.99 years.

열대 해양의 해수면온도와 구름의 상호관계 (Interrelationships between Sea Surface Temperatures and Clouds over the Tropical Oceans)

  • 송봉근;김영섭;박경원
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2001년도 춘계 학술대회 논문집 통권 4호 Proceedings of the 2001 KSRS Spring Meeting
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    • pp.92-97
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    • 2001
  • The intra-annual and interannual variations of total, high, middle, low clouds, and cloud forcing net solar radiation flux, cloud forcing net long-wave radiation flux, and SSTs over the tropical oceans are investigated with the use of ISCP D2, NCEP/NCAR Reanalysis for January 1983-December 1993. The intra-annual variation of total cloudiness is dominated by high and middle clouds in the western Pacific and central tropical oceans, the interannual variation of total cloudiness is also dominated by high and middle clouds in the central Pacific and Atlantic. The dominant intra-annual and interannual EOFs of total cloudiness have spatially coherent link with those SSTs. For the interannual EOFs, total cloudiness and SSTs are related to E1 nino-Southern Oscillation(ENSO). The second most important intra-annual EOFs of total cloudiness are related to Inter Tropical Convergence Zone(ITCZ). The third most important intra-annual EOFs show coherent relation in the western Pacific. The correlation analysis between cloud radiative effects and SSTs show spatially coherent relation over the tropical oceans even though cloud forcing cooling effect is much higher than heating effect.

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고리 주변해역 통발에서 채집된 십각류 종조성의 계절변동과 연간변동 (Seasonal and Interannual Variation in Species Composition and Abundance of Decapod Assemblages Collected using Pots in the Coastal Waters off Gori, Korea)

  • 허성회;박주면;정달상;백근욱
    • 한국수산과학회지
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    • 제43권5호
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    • pp.503-509
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    • 2010
  • The seasonal and interannual variation in the species composition and abundance of the decapod assemblage (shrimps, crabs, and hermit crabs) collected using pots in the coastal waters off Gori were studied between 2005 and 2008. During the study period, 49 decapod species belonging to 19 families were collected. The dominant species were Crangon hakodatei, Pandalus gracilis, Carcinoplax longimana, Charybdis bimaculata, Carcinoplax vestita, Diogenes edwardsii, and Dardanus arrosor. These seven species accounted for 95.46% of the total number of individuals collected. The number of species, number of individuals, biomass, and species diversity indices fluctuated with the seasons. The peak number and biomass of individuals occurred in July 2006. The number and biomass of individuals were higher in summer and lower in winter, and the diversity indices were lower in summer than in the other seasons. The abundance of dominant species showed some seasonal and interannual change; in particular, those of C. hakodatei and P. gracilis corresponded with the bottom water temperature.

Intercomparison of interannual changes in NDVI from PAL and GIMMS in relation to evapotranspiration over northern Asia

  • Suzuki Rikie;Masuda Kooiti;Dye Dennis
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.162-165
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    • 2004
  • The authors' previous study found an interannual covariability between actual evapotranspiration (ET) and the Normalized Difference Vegetation Index (NDVI) over northern Asia. This result suggested that vegetation controls interannual variation in ET. In this prior study, NDVI data from the Pathfinder AVHRR Land (PAL) dataset were analyzed. However, studies of NDVI interannual change are subject to uncertainty, because NDVI data often contain errors associated with sensor- and atmosphere-related effects. This study is aimed toward reducing this uncertainty by employing NDVI dataset, from the Global Inventory Monitoring and Modeling Studies (GIMMS) group, in addition to PAL. The analysis was carried out for the northern Asia region from 1982 to 2000. 19-year interannual change in PAL-NDVI and GIMMS-NDVI were both compared with interannual change in model-assimilated ET. Although the correlation coefficient between GIMMS-NDVI and ET is slightly less than for PAL-NDVI and ET, for both NDVI datasets the annual maximum correlation with ET occurs in June, which is near the central period of the growing season. A significant positive correlation between GIMMS-NDVI and ET was observed over most of the vegetated land area in June as well as PAL-NDVI and ET. These results reinforce the authors' prior research that indicates the control of interannual change in ET is dominated by interannual change in vegetation activity.

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열대 및 아열대 SST에 관련된 동아시아 강우량의 경년 변동성 (Interannual variabilities of the East Asia precipitation associated with tropical and subtropical sea surface temperature)

  • 하경자
    • 한국환경과학회지
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    • 제4권5호
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    • pp.28-28
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    • 1995
  • The aim of the present study is to investigate the interannual variabilities of the East Asia monsoon rainfall associated with the global sea surface temperature anomaly(SSTA). For this study, the summer rainfall(from June to August) over the twenty-eight period of 1961-1988 were analyzed with being divided by nine-subregions over East Asia including Korea, China and Japan. From the analysis of the principal modes explaining the interannual variation, the interannual variabilities of summer rainfalls in South Japan and Korea are larger than those of the other subregions of the East Asia. There is a strong negative correlation between the summer rainfalls of south China and Korea. In this study, the relationship between the summer monsoon of each subregion and SSTs of the tropical NINO regions, of western Pacific warm pool, and of the subtropical ocean were investigated. The longitudinal sections of the lagged cross correlations of the summer rainfal1 anomaly in (a) Korea and (b) south China, and the monthly SSTA in the equatorial(averaged from 65 to 6N) Pacific were analyzed. The negative maximum correlation pattems of Korea''s stammer rainfal1 and SSTs over the eastern Pacific is transfered to positive maximum conrlation over central Pacific region with a biennial periodicity. In South China, the significant positive correlations are found at -12 month lag over the eastern Pacific and maximum negative correlation at 16 month lag over the central Pacific with the quasi-biennial oscillation. But the correlation coefficient reverses completely to that in Korea. In order to investigate the most prevailing interannual variability of rainfall related to the favored SSTA region, the lagged cross correlations between East Asia rainfall and SSTs over the moO regions(NINO 1+2(0-105, 90W-80W), NINO 3(5N-5S, 150W-90W), NINO 4(5N-5S, 160E-l50W) and the western Pacific worm pool (5N-5S, 120E-l60E) were analyzed. Among the lagged cross-correlation cycles in NINO regions, the maximum correlations for the negative lagged months prevail in NINO 1+2 and NINO 3, and the cross correlations for the positive lagged months NINO 4. It is noteworthy that correlation between the western Pacific warm pool SSTA and the monsoon rainfall in Korea and South China have the maximum value at negative 4 month lag. The evolution of the correlation between the East Asia monsoon rainfall and SSTA is linked to the equatorial convective cluster and related to northward propagating situation, and raising the possibility that the East Asia monsoon precipitation may be more fundamentally related to the interaction of intraseasonal oscillations and the sub-regional characteristics including the surface boundary conditions and the behavior of climatological air mass.

열대 및 아열대 SST에 관련된 동아시아 강우량의 경년 변동성 (Interannual variabilities of the East Asia precipitation associated with tropical and subtropical sea surface temperature)

  • 하경자
    • 한국환경과학회지
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    • 제4권5호
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    • pp.413-426
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    • 1995
  • The aim of the present study is to investigate the interannual variabilities of the East Asia monsoon rainfall associated with the global sea surface temperature anomaly(SSTA). For this study, the summer rainfall(from June to August) over the twenty-eight period of 1961-1988 were analyzed with being divided by nine-subregions over East Asia including Korea, China and Japan. From the analysis of the principal modes explaining the interannual variation, the interannual variabilities of summer rainfalls in South Japan and Korea are larger than those of the other subregions of the East Asia. There is a strong negative correlation between the summer rainfalls of south China and Korea. In this study, the relationship between the summer monsoon of each subregion and SSTs of the tropical NINO regions, of western Pacific warm pool, and of the subtropical ocean were investigated. The longitudinal sections of the lagged cross correlations of the summer rainfal1 anomaly in (a) Korea and (b) south China, and the monthly SSTA in the equatorial(averaged from 65 to 6N) Pacific were analyzed. The negative maximum correlation pattems of Korea's stammer rainfal1 and SSTs over the eastern Pacific is transfered to positive maximum conrlation over central Pacific region with a biennial periodicity. In South China, the significant positive correlations are found at -12 month lag over the eastern Pacific and maximum negative correlation at 16 month lag over the central Pacific with the quasi-biennial oscillation. But the correlation coefficient reverses completely to that in Korea. In order to investigate the most prevailing interannual variability of rainfall related to the favored SSTA region, the lagged cross correlations between East Asia rainfall and SSTs over the moO regions(NINO 1+2(0-105, 90W-80W), NINO 3(5N-5S, 150W-90W), NINO 4(5N-5S, 160E-l50W) and the western Pacific worm pool (5N-5S, 120E-l60E) were analyzed. Among the lagged cross-correlation cycles in NINO regions, the maximum correlations for the negative lagged months prevail in NINO 1+2 and NINO 3, and the cross correlations for the positive lagged months NINO 4. It is noteworthy that correlation between the western Pacific warm pool SSTA and the monsoon rainfall in Korea and South China have the maximum value at negative 4 month lag. The evolution of the correlation between the East Asia monsoon rainfall and SSTA is linked to the equatorial convective cluster and related to northward propagating situation, and raising the possibility that the East Asia monsoon precipitation may be more fundamentally related to the interaction of intraseasonal oscillations and the sub-regional characteristics including the surface boundary conditions and the behavior of climatological air mass.

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북반구 하부성층권 극기온의 경년변화와 수십년주기변화의 수치모의 (A Numerical Simulation of the Interannual and Decadal Variations of the Northern Lower Stratospheric Polar Temperature)

  • 최우갑;김유진;김동준
    • 대기
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    • 제19권1호
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    • pp.79-91
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    • 2009
  • Seoul National University General Circulation Model (SNUGCM) has been run for 100 years to obtain daily temperature and meridional velocity at the Northern lower stratosphere. The model results are compared with the NCEP/NCAR reanalysis data. The polar temperature and the eddy heat flux from the model show that the model-produced climatology has well-known cold bias and weaker planetary wave activities. The model climatology also has a lag in the seasonal evolution. The relationship between the model-produced polar temperature and the eddy heat flux is investigated with respect to the interannual and decadal time scales. The interannual variation of the polar temperature is related with both total and stationary eddy heat flux in January and March, which is in agreement with observation. The model, however, does not reproduce the relationship between the decadal variation of the polar temperature and transient eddy heat flux, which is revealed in the observed data.

동해 남부 연안해역 통발에서 채집된 어류 군집의 계절변동과 연간변동 (Seasonal and Interannual Variation in Species Composition of Fish Assemblages Collected by Pots in the Southern Coast of East Sea, Korea)

  • 박주면;허성회
    • 한국어류학회지
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    • 제27권4호
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    • pp.310-316
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    • 2015
  • 본 연구는 동해 남부 연안해역 통발에서 채집된 어류 종조성의 계절 및 연간변동을 조사하였다. 어류 시료는 2005년에서 2008년까지 계절별로 채집하였다. 조사기간 동안 24과에 속하는 32종의 어류가 채집되었다. 우점종은 붕장어 (Conger myriaster), 미역치 (Paracentropogon rubripinnis), 꼼치 (Liparis tanakae), 쌍동가리 (Parapercis sexfasciata), 먹장어 (Eptatretus burgeri), 청어 (Clupea pallasii pallasii)였으며, 이들 6종은 총채집개체수의 91.9%를 차지하였다. 어류 군집의 출현종수, 개체수, 생체량, 다양도는 계절변동을 나타내었는데, 출현종수와 개체수는 2008년 8월에 가장 높았고, 생체량과 다양도는 2005년 8월에 가장 높았다. ANOSIM 분석 결과, 2008년 어류 종조성은 다른 년도와 유의한 차이를 나타내었다. 반면 계절별 채집 종조성은 유의한 차이를 보이지 않았다.

한국 연안 표층수온의 경년변동과 장기변화 (Interannual Variability and Long-term Trend of Coastal Sea Surface Temperature in Korea)

  • 민홍식;김철호
    • Ocean and Polar Research
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    • 제28권4호
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    • pp.415-423
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    • 2006
  • Interannual variation and long-term trends of coastal sea surface temperature (SST) in Korea were investigated by analyzing 27 coastal SST time series from 1969 to 2004. Long-term linear increasing trend was remarkable with the rate over $0.02^{\circ}C/year$ at almost all the stations. The slope of long-term linear trend was larger at the stations along the eastern coast than in the western and southern regions. It was also noticeable that there was a common tendency of interannual variability with the period of 3-5 years at most of the stations. SST was lower in the 1970's and early 1980's while it was higher in the 1990's and early 2000's after the increase in the late 1980's. The pattern of the interannual variability of SST was similar to that of air temperature. Increasing trend of minimum SST in winter was obvious at most stations na it was larger along the eastern coast, while the linear trend of maximum SST in summer was less definite. Therefore, the decreasing tendency of annual amplitude was mainly due to the increasing tendency of SST in winter.

열대 및 북태평양에서 ENSO와 관련된 표층수온과 해면고도의 경년 변동성 (Interannual Variabilities of Sea Surface Temperature and Sea Level Anomaly related to ENSO in the Tropical and North Pacific Ocean System)

  • 김응;전동철
    • Ocean and Polar Research
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    • 제30권3호
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    • pp.313-324
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    • 2008
  • In order to understand the variation of ENSO-related oceanic environments in the tropical and North Pacific Ocean, spatio-temporal variations of sea surface temperature anomaly (SSTA) and sea surface height anomaly (SSHA) are analyzed from distributions of complex empirical orthogonal functions (CEOF). Correlations among warm pool variation, southern oscillation index, and ocean surface currents were also examined with respect to interannual variability of the warm pool in western tropical Pacific. Spatio-temporal distributions of the first CEOF modes for SSTA and SSHA indicate that their variabilities are associated with ENSO events, which have a variance over 30% in the North Pacific. The primary reasons for their variabilities are different; SST is predominantly influenced by the change of barrier layer thickness, while SSH fluctuates with the same phase as propagation of an ENSO episode in the zonal direction. Horizontal boundary of warm pool area, which normally centered around $149^{\circ}E$ in the tropics, seemed to be expanded to the middle and eastern tropical regions by strong zonal currents through the mature phase of an ENSO episode.