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The Role of the Kuroshio in the Winter North Pacific Ocean-Atmosphere Interaction: Comparison of a Coupled Model and Observations
The Role of the Kuroshio in the Winter North Pacific Ocean-Atmosphere Interaction: Comparison of a Coupled Model and Observations

LIU Qinyu,WEN Na,YU Yongqiang,
LIU Qinyu
,WEN N,YU Yongqiang

大气科学进展 , 2006,
Abstract: A comparative study between the output of the Flexible Global Climate Model Version 1.0 (FGCM-1.0) and the observations is performed. At 500 hPa, the geopotential height of FGCM is similar to the observations, but in the North Pacific the model gives lower values, and the differences are most significant over the northern boundary of the Pacific. In a net heat flux comparison, the spatial patterns of the two are similar in winter, but more heat loss appears to the east of Japan in FGCM than in COADS. On the interannual timescale, strong (weak) Kuroshio transports to the east of Taiwan lead the increasing (decreasing) net heat flux, which is centered over the Kuroshio Extension region, by 1-2 months, with low (high) pressure anomaly responses appearing at 500 hPa over the North Pacific (north of 25°N) in winter.The northward heat transport of the Kuroshio is one of the important heat sources to support the warming of the atmosphere by the ocean and the formation of the low pressure anomaly at 500 hPa over the North Pacific in winter.
Interannual and Seasonal Variability of Winter-Spring Cohort of Neon Flying Squid Abundance in the Northwest Pacific Ocean During 1995–2011 Interannual and Seasonal Variability of Winter-Spring Cohort of Neon Flying Squid Abundance in the Northwest Pacific Ocean During 1995–2011  [PDF]
YU Wei,CHEN Xinjun,YI Qian
- , 2016,
Abstract: The neon flying squid, Ommastrephes bartramii, is a species of economically important cephalopod in the Northwest Pacific Ocean. Its short lifespan increases the susceptibility of the distribution and abundance to the direct impact of the environmental conditions. Based on the generalized linear model(GLM) and generalized additive model(GAM), the commercial fishery data from the Chinese squid-jigging fleets during 1995 to 2011 were used to examine the interannual and seasonal variability in the abundance of O. bartramii, and to evaluate the influences of variables on the abundance(catch per unit effort, CPUE). The results from GLM suggested that year, month, latitude, sea surface temperature(SST), mixed layer depth(MLD), and the interaction term(SST×MLD) were significant factors. The optimal model based on GAM included all the six significant variables and could explain 42.43% of the variance in nominal CPUE. The importance of the six variables was ranked by decreasing magnitude: year, month, latitude, SST, MLD and SST×MLD. The squid was mainly distributed in the waters between 40?N and 44?N in the Northwest Pacific Ocean. The optimal ranges of SST and MLD were from 14 to 20℃ and from 10 to 30 m, respectively. The squid abundance greatly fluctuated from 1995 to 2011. The CPUE was low during 1995–2002 and high during 2003–2008. Furthermore, the squid abundance was typically high in August. The interannual and seasonal variabilities in the squid abundance were associated with the variations of marine environmental conditions and the life history characteristics of squid
Storm track variations in the North Pacific in winter season and the coupled pattern with the midlatitude atmosphere-ocean system
北太平洋风暴轴的变异特征及其与中纬度海气耦合关系分析

REN Xue-Juan,YANG Xiu-Qun,HAN Bo,XU Gui-Yu,
任雪娟
,杨修群,韩博,徐桂玉

地球物理学报 , 2007,
Abstract: The storm track variations in the North Pacific in winter are investigated by using European ECMWF(ERA40) reanalysis data and the Empirical Orthogonal Function(EOF) method.The coupled patterns of the atmosphere mean flow anomaly and the sea surface temperature(SST) anomaly,related with the storm track variations are studied by the regression method.The results show that there are two main variation modes of the storm track in the North Pacific in winter.The first type is characterized by north(south) shift of the mid-east part of the storm track that connotes a northeastward(southeastward) reorientation of the track.The regression analysis shows that the warmer(colder) SSTA occurs in conjunction with anticyclonic anomalies above that cover the midlatitude North Pacific,companying with the first mode of the storm track.Those are warm ridge(cold trough) pattern in the vertical for the atmosphere-ocean system.Meanwhile,it is Pacific-North American(PNA) negative(positive) phase at the mid and high troposphere.The second type is the intensification(weakening) and northward(southward) shift of the whole storm track.It is associated with warmer(colder) SST in the Kuroshio Current,northward(southward) shift of the Aleutian Low at the low troposphere and westerly jet at the high troposphere,and Western Pacific(WP) negative(positive) phase at the mid-high troposphere.The time coefficients of EOF have significant correlation with Aleutian Low index,PNA index,WP index,Nino-3 index and the Kuroshio Current index,respectively,which demonstrate the existence of the coupling among the three selected fields.
Dynamic Linkage between the North Pacific and the Tropical Pacific: Atmosphere--Ocean Coupling

LI Chun,WU Lixin,

大气科学进展 , 2013,
Abstract: In this study, dynamic linkage of atmosphere-ocean coupling between the North Pacific and the tropical Pacific was demonstrated using a large number of ensemble perturbed initial condition experiments in a fully coupled fast ocean-atmosphere model (FOAM). In the FOAM model, an idealized mixed layer warming was initiated in the Kuroshio-Oyashio extension region, while the ocean and atmosphere remained fully coupled both locally and elsewhere. The modeling results show that the warm anomalies are associated with anomalous cyclonic winds, which induce initial warming anomalies extending downstream in the following winter. Then, the downstream warming spreads southwestward and induces SST warming in the equatorial Pacific via surface wind-evaporation-SST feedback. Warming in the tropical Pacific is further reinforced by Bjerknes’ feedback.
The Effect of Regional Ocean-Atmosphere Coupling on the Long-term Variability in the Pacific Ocean

Lin Feng,Dexing Wu,Xiaopei Lin,Xiangfeng Meng,

大气科学进展 , 2010,
Abstract: A fully coupled ocean-atmosphere model is applied to highlight the mechanism of the long-term variability (including decadal and longer time scales) in the Pacific Ocean. We are interested in the effect of ocean-atmosphere coupling of different regions during these processes. The control run successfully simulates the Pacific long-term variability, whose leading modes are the Pacific (inter) Decadal Oscillation (PDO) and the North Pacific mode (NPM). Furthermore, three numerical experiments are conducted, s...
The Interdecadal Variation of Winter Temperature in China and Its Relation to the Anomalies in Atmospheric General Circulation
我国冬季气温年代际变化及其与大气环流异常变化的关系

KANG Li-Hu,CHEN Wen,WEI Ke,
康丽华
,陈文,魏科

气候与环境研究 , 2006,
Abstract: By using the monthly temperature in 160 stations of China and the NCEP/NCAR reanalysis data,the winter(November to March) temperature variations from 1951 to 2000 are studied with the empirical orthogonal function(EOF) analysis.The first EOF has an identical signal in whole China and demonstrates that the winter temperature has increased since the middle of 1970s in China.The second EOF has a seesaw pattern between southern and northern China and shows a warming in the 1980s and 1990s in Northwest China and Northeast China.The interdecadal variation with periods longer than 8 years can also be revealed using Fourier harmonics analysis.In addition,the warming superimposition of EOF1 and EOF2 probably causes persistent warming winter in China from the 1980s.This significant warming may intensify the drought in North China,since there are no obvious changes in the regional precipitation.The linear regressions of the atmospheric general circulation upon the winter temperature on interdecadal time scales indicate that the first EOF of temperature is significantly correlated to the Arctic Oscillation(AO),with a quasi-barotropic annular mode in the geopotential height field.However,the second EOF of temperature is closely associated with height anomalies of wavenumber one in middle-high latitudes,with a quasi-barotropic out-of-phase oscillation between the Pacific Ocean and the Atlantic Ocean.The results show that the interdecadal variations of winter temperature in China are closely related to the basic flows and perturbations in the atmosphere.The possible mechanisms of the atmospheric general circulation influencing the winter temperature in China are discussed and the questions needed to be further studied are presented.
Rainfall Variations Due to Twin Typhoons over Northwest Pacific Ocean
Shengyan Yu, M. V. Subrahmanyam
Open Access Library Journal (OALib Journal) , 2017, DOI: 10.4236/oalib.1103638
Abstract:
This paper focuses on the investigation of the rainfall variations due to twin typhoons Saola and Damrey occurred in 2012 over Northwest Pacific Ocean (NPO). Genesis and landfall of the two typhoons are on the same day, however the track and rainfall area are different. We have chosen the Global Precipitation Climatology Project (GPCP) and Tropical Rainfall Measuring Mission (TRMM) data for this analysis. The results are illustrating as follows: typhoon Saola produced higher rainfall than typhoon Damery. The rainfall pattern of typhoon Saola having sufficient affect typhoon Damrey rainfall over the ocean, however after landfall produced rainfall over the land. Comparison of two rainfall data sets revealing that TRMM data is better for identifying heavy rainfall due to typhoon.
The Oscillation between Tropical Indian Ocean and North Pacific:Evidence and Possible Impact on Winter Climate in China
The Oscillation between Tropical Indian Ocean and North Pacific: Evidence and Possible Impact on Winter Climate in China

HU Kai-Ming,HUANG Gang,
HU Kai-Ming
,HUANG Gang

大气和海洋科学快报 , 2011,
Abstract: This paper provides evidence that the variation of boreal winter sea level pressure (SLP) over the North Pacific is out-of-phase with SLP fluctuation over the tropical Indian Ocean on both the interdecadal and interannual time scales. Subsequently, a SLP between tropical Indian Ocean and North Pacific (TIO-NP) oscillation index is defined to indicate the variation of such out-of-phase fluctuation. Moreover, the simultaneous surface air temperature and precipitation anomalies in China are closely related to TIO-NP oscillations. Below-normal surface air temperature anomalies in the northern and the eastern part of China, and less rainfall in southern China, correspond to positive TIO-NP oscillation phase with negative SLP anomalies in tropical Indian Ocean and positive anomalies in North Pacific. The TIO-NP oscillation affects China’s winter climate anomalies, possibly through modulating the northeast East Asia winter monsoon.
The Last Frontier: Catch Records of White Sharks (Carcharodon carcharias) in the Northwest Pacific Ocean  [PDF]
Heather M. Christiansen, Victor Lin, Sho Tanaka, Anatoly Velikanov, Henry F. Mollet, Sabine P. Wintner, Sonja V. Fordham, Aaron T. Fisk, Nigel E. Hussey
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0094407
Abstract: White sharks are highly migratory apex predators, globally distributed in temperate, sub-tropical, and tropical waters. Knowledge of white shark biology and ecology has increased recently based on research at known aggregation sites in the Indian, Atlantic, and Northeast Pacific Oceans; however, few data are available for the Northwest Pacific Ocean. This study provides a meta-analysis of 240 observations of white sharks from the Northwest Pacific Ocean between 1951 and 2012. Records comprise reports of bycatch in commercial fisheries, media accounts, personal communications, and documentation of shark-human interactions from Russia (n = 8), Republic of Korea (22), Japan (129), China (32), Taiwan (45), Philippines (1) and Vietnam (3). Observations occurred in all months, excluding October-January in the north (Russia and Republic of Korea) and July-August in the south (China, Taiwan, Philippines, and Vietnam). Population trend analysis indicated that the relative abundance of white sharks in the region has remained relatively stable, but parameterization of a 75% increase in observer effort found evidence of a minor decline since 2002. Reliably measured sharks ranged from 126–602 cm total length (TL) and 16–2530 kg total weight. The largest shark in this study (602 cm TL) represents the largest measured shark on record worldwide. For all countries combined the sex ratio was non-significantly biased towards females (1:1.1; n = 113). Of 60 females examined, 11 were confirmed pregnant ranging from the beginning stages of pregnancy (egg cases) to near term (140 cm TL embryos). On average, 6.0±2.2 embryos were found per litter (maximum of 10) and gestation period was estimated to be 20 months. These observations confirm that white sharks are present in the Northwest Pacific Ocean year-round. While acknowledging the difficulties of studying little known populations of a naturally low abundance species, these results highlight the need for dedicated research to inform regional conservation and management planning.
A local positive feedback of the tropical Pacific ocean-atmosphere system on interdecadal timescales
Chunhui Li,Dongxiao Wang,Jianyin Liang,Dejun Gu,Yun Liu
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-0601-y
Abstract: Interdecadal variability characteristics of ocean-atmosphere interaction in the tropical areas are investigated by using atmospheric reanalysis data and oceanic dataset. Results indicate that due to the ocean-atmosphere system’s internal adjustment on interdecadal time scales, the exchanges of latent heat and sensible heat between the ocean and atmosphere are reduced by means of weakening trade wind, causing oceanic thermocline anomalies and resulting in unusual warming of sea surface temperature in the central and eastern Pacific. Meanwhile the increases of sea surface temperature facilitate much more development of convection in the eastern Pacific and excite a local ascending motion in the eastern and anomalous westerlies in the central and eastern Pacific, which further weaken the Walker circulation, and vice versa. Thus these processes constitute an interdecadal mode of positive feedback. This interdecadal feedback of the tropical oceanatmosphere system is different from the previous conclusion of a so-called midlatitude-driving mechanism, which was used to explain the decadal variability in the tropical Pacific Ocean.
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