• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.167-168
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• 2000

A North Pacific Ocean Model has been developed with the Global Ocean Model of the Meteorological Research Institute of Japan which solves the primitive equations with Boussinesq, rigid-lid, and hydrostatic assumptions. The objective of the study is to improve the description of the variability on the East Sea and northwestern Pacific Ocean. (omitted)

• Ocean and Polar Research
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• v.37 no.3
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• pp.189-200
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• 2015

Mesozooplankton biomass including total biomass and size-fractionated biomass and the abundance of major taxonomic groups of copepods were studied in the Northwestern Subtropical Pacific Warm Pool (NSPWP) and the Northern East China Sea (NECS) from 2006 to 2014. Mesozooplankton biomass ranged from 0.69 to $3.08mgC/m^3$ (mean $1.12mgC/m^3$) in the NSPWP and from 10.60 to $69.10mgC/m^3$ (mean $30.33mgC/m^3$) in the NECS with higher values in spring than fall. Percent composition in the biomass of each size group of mesozooplankton varied interannually both in the NSPWP and in the NECS. The smallest size group (0.2~0.5 mm) contributed the least to total biomass in both regions, but significantly higher in the NSPWP than in the NECS. The percent composition in abundance of copepod taxonomic groups (i.e. Calanoida, Cyclopoida, and Poecilostomatoida) also fluctuated interannually. Mean composition of calanoid copepods was higher in the NECS than in the NSPWP, but the opposite pattern was observed for poecilostomatoid copepods. Mesozooplankton biomass both in the NSPWP and in the NECS was negatively correlated with Oceanic $Ni{\tilde{n}}o$ Index (ONI), indicating declines in biomass during El $Ni{\tilde{n}}o$ periods and vice versa during Na $Ni{\tilde{n}}a$ period. The effect of El $Ni{\tilde{n}}o$ on variation of mesozooplankton biomass was more prominent in the NSPWP than in the NECS. These results suggest that mesozooplankton biomass both in the NSPWP and in the NECS responded to El $Ni{\tilde{n}}o$ events, although the biological process that explain the reduced mesozooplankton biomass might be different in both regions.

• Ocean and Polar Research
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• v.38 no.1
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• pp.1-19
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• 2016

Recently, there has been a growing interest in physical-biological ocean-modeling systems by communities in the fields of science and business. In this paper, we present preliminary results from a coupled physical-biological model for the Northwestern Pacific marginal seas. The ocean circulation component is an implementation of the Regional Ocean Modeling System (ROMS), and the lower trophic level ecosystem component is a Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD) model. The ROMS-NPZD coupled system, with a 25 km resolution, is forced by climatological atmospheric data and predicts the physical variables and concentrations of nitrate, phytoplankton, zooplankton, and detritus. Model results are compared with remote-sensed sea surface temperature and chlorophyll, and with climatological sea surface salinity and nitrate. Our model adequately reproduces the observed spatial distribution and seasonal variability of nitrate and chlorophyll concentrations as well as physical variables, showing a high correlation in the East Sea (ES) and Kuroshio/Oyashio Extension (KOE) region but relatively low correlation in the Yellow Sea (YS) and East China Sea (ECS). Although some deficiencies were found in the biological components, such as the over/underestimation of the intensity of phytoplankton blooms in the ES and KOE/the YS and ECS, our system demonstrates the capability of the model to capture and record dominant seasonal variability in physical-biological processes and this holds out the promise of coming to a better understanding of such processes and making better predictions .

• Atmosphere
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• v.18 no.4
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• pp.279-286
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• 2008

In the tropical western Pacific (especially, west of 135oE, including South China Sea and the Philippines), during boreal summer, it was found that a strong correlation exists between the tropical cyclone activity and the drought conditions in Korea. During the summer drought, firstly, there were strong ascending flows over the tropical western Pacific with more tropical cyclone genesis, and to compensate for this, descending flows develop in the mid-latitudes, thereby causing drought; in other words, a secondary circulation is formed between the tropical western Pacific and mid-latitudes of East Asia. Secondly, the developments of both the subtropical western Pacific high and the Manchurian low are suppressed. As a result, both the land-sea pressure gradient and the southerly flow from low-latitudes to Korean area are also weakened, which reduces approaches of tropical cyclones to this area despite the high frequency of their geneses.

• 한국전산유체공학회:학술대회논문집
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• 2006.05a
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• pp.129-132
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• 2006

A Pacific Ocean circulation model based on the RIAM Ocean Model (RIAMOM) with $1/6^{\circ}C\;and\;1/12^{\circ}C$ horizontal resolution successfully reproduced the peculiar circulation structures of the Pacific Ocean. The volume transports of model agree very well with the results of observations in the northwestern Pacific Ocean. Also our model successfully reproduced the observed structures of the northeastward Ryukyu Current with a subsurface core at $500{\sim}600m$. A Possible mechanism for the subsurface current core of the Ryukyu Current is proposed focusing on the blocking effect of the Ryukyu Island Chain.

• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.118-124
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• 2009

A Korean trawl fishery was conducted on the Emperor Seamounts in the northwestern Pacific Ocean from 2005 to 2007. Total catches were 750 mt, 460 mt and 440 mt in 2005, 2006 and 2007, respectively. Splendid alfonsino (Beryx splendens) and North Pacific armorhead (Pseudopentaceros wheeleri) were dominant in the commercial fisheries on the Emperor Seamounts during 2005-2007. Biomass of each species was estimated by the swept area method from March 2005 to August 2007. During three years, average biomass of Splendid alfonsino and North Pacific armorhead were 791 mt and 266 mt, respectively.

• Journal of the Korean earth science society
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• v.31 no.5
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• pp.454-464
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• 2010

A probability prediction model for tropical cyclone (TC) genesis in the Northwestern Pacific area was developed using the logistic regression method. Total five predictors were used in this model: the lower-level relative vorticity, vertical wind shear, mid-level relative humidity, upper-level equivalent potential temperature, and sea surface temperature (SST). The values for four predictors except for SST were obtained from difference of spatial-averaged value between May and January, and the time average of Ni$\tilde{n}$o-3.4 index from February to April was used to see the SST effect. As a result of prediction for the TC genesis frequency from June to December during 1951 to 2007, the model was capable of predicting that 21 (22) years had higher (lower) frequency than the normal year. The analysis of real data indicated that the number of year with the higher (lower) frequency of TC genesis was 28 (29). The overall predictability was about 75%, and the model reliability was also verified statistically through the cross validation analysis method.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.225-229
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• 2012

Background: Males have a higher prevalence of hepatocellular carcinoma (HCC) than females in general, but the reasons for the sex disparity are still obscure. DNA copy number alteration (CNA) is a major feature of solid tumors including HCC, but whether CNA plays a role in sex-related differences in HCC development has never been evaluated. Methods: High-resolution array comparative genomic hybridization (CGH) was used to examine 17 female and 46 male HCC patients with chronic hepatitis B virus (HBV) infection in Shanghai, China. Two-tailed Fisher's exact or ${\chi}^2$ tests was used to compare CNAs between females and males. Results: The overall frequencies and patterns of CNAs in female and male cases were similar. However, female HCC tumors presented more copy number gains compared to those in males on 1q21.3-q22 (76.5% vs. 37.0%, P = 0.009), 11q11 (35.3% vs. 0.0%, P = 0.0002) and 19q13.31-q13.32 (23.5% vs. 0.0%, P = 0.004), and loss on 16p11.2 (35.3% vs. 6.5%, P = 0.009). Relative to females, male cases had greater copy number loss on 11q11 (63.0% vs. 17.6%, P = 0.002). Further analyses showed that 11q11 gain correlated with 19q13.31-q13.32 gain (P = 0.042), 11q11 loss (P = 0.011) and 16p11.2 loss (P = 0.033), while 1q21.3-q22 gain correlated with 19q13.31-q13.32 gain (P = 0.046). Conclusions: These findings suggest that CNAs may play a role in sex-related differences in HBVassociated HCC development.

• Ocean and Polar Research
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• v.33 no.spc3
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• pp.385-395
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• 2011

Time-series sediment traps were deployed at 1,000 m water depth of the northwestern subtropical Pacific from July 2009 to June 2010, with the aim of understanding temporal and spatial variations of sinking-particle fluxes. The opening and closing of the traps was synchronized at 18-day periods for 20 events. Total mass fluxes showed distinct seasonal variations with high values for the summer-fall seasons and relatively low values for winter-spring. This seasonal variation at two stations was characterized by a distinct difference in $CaCO_3$ fluxes between the two seasons. The enhanced $CaCO_3$ flux in the summer - fall seasons might be attributed to an increased planktonic foraminiferal flux. Total mass flux at FM10 station was nearly 50% higher than that at FM1 station. The difference in $CaCO_3$ fluxes between two stations contributed nearly 70% of the difference of total mass fluxes. The $CaCO_3$ flux was a major component controlling temporal and spatial variation of sinking - particle fluxes in the western subtropical Pacific Ocean.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.52-53
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• 2005

Time series of gridded surface wind and wind-stress vectors over the world ocean have been constructed by satellite scatterometer data. The products are derived from the ERS-l,2 covering 9 years during 1992-2000 and the Sea Winds on board QuikSCAT (Qscat) which has been operating up to the present since June 1999, so they allows us to analyze variabilities with various time scales. In this study, we focus on interannual variability of the wind stress in the mid- and high-latitude region of North Pacific. These are compared with those by numerical weather prediction(NWP) ones (NCEP Reanalysis). We also examine variability in the wind-stress curl field that is an important factor for ocean dynamics and focus its time and spatial characters in the northwestern Pacific around Japan. It is found that the vorticity field in the lower atmosphere tends to increase gradually with time, suggesting the enhancement of the North Pacific subtropical gyre.