Subinertial fluctuation of a strong northward deep current, which is referred to the Dokdo Abyssal Current (DAC) by Chang et al. (2009), is investigated from current records for about 16.5 and 8.0 months in the Ul...Subinertial fluctuation of a strong northward deep current, which is referred to the Dokdo Abyssal Current (DAC) by Chang et al. (2009), is investigated from current records for about 16.5 and 8.0 months in the Ulle- ung Interplain Gap of the East/lapan Sea. The current below 300 m is bottom-intensified and has nearly depth-independent flow. Near bottom, the spectral peaks of the current were found near 10, 20, and 60 d. The DAC variability near 10 d and 20 d is reasonably consistent with the linear theory of topographic Rossby waves (TRWs) in the following aspects: (1) The motion is columnar and bottom-intensified; (2) the theo- retical cutoff frequency is similar to the observation; (3) The observation-based angles of the wavenumber vector are in good agreement with the theoretical ones. The wavelengths of the TRWs with periods of near 10 d and 20 d near Dokdo are significantly shorter than those with similar timescales in the open oceans (100-250 km). It is primarily due to the weak stratification below 300 m in the East Sea. The deep cur- rent fluctuations with periods of near 10 d and 20 d were accompanied by warm events in the upper layer resulting from eddying processes and/or meandering of the Tsushima Warm Current.展开更多
In this study the structure and seasonal variations of deep mean circulation in the East/lapan Sea (E/S) were numerically simulated using a mid-resolution ocean general circulation model with two different parameter...In this study the structure and seasonal variations of deep mean circulation in the East/lapan Sea (E/S) were numerically simulated using a mid-resolution ocean general circulation model with two different parameterizations for the eddy-topography interaction (ETI). The strong deep mean circulations observed in the EIS are well reproduced when using the ETI parameterizations. The seasonal variability in the EIS deep layer is shown by using ETI parameterization based on the potential vorticity approach, while it is not shown in the statistical dynamical parameterization. The driving mechanism of the strong deep mean currents in the E/S are discussed by investigating the effects of model grids and parameterizations. The deep mean circulation is more closely related to the baroclinic process and potential vorticity than it is to the wind driven circulation.展开更多
Crustal deformation can provide constraints for studying earthquake rupture and shock wave transmission for the Mw9.0 eastern Japan great earthquake. Using the single- epoch precise point positioning (PPP) method an...Crustal deformation can provide constraints for studying earthquake rupture and shock wave transmission for the Mw9.0 eastern Japan great earthquake. Using the single- epoch precise point positioning (PPP) method and the appropriate positioning flow, we process GPS data from six IGS (International GNSS Service) sites (e.g., MIZU, TSK2, USUD, MTKA, AIRA and KSMV) located in Japan and obtain the positioning results with centimeter scale precision. The displacement time series of the six sites are analyzed using the least squares spectral analysis method to estimate deformations caused by the Mw9.0 mainshock and the Mw7.9 aftershock, and the cumulative displacements after 1 day. Mainshock displacements at station MIZU, the nearest site to the mainshock in the North (N), East (E), and Up (U) directions, are -1.202 m, 2.180 m and -0.104 m, respectively, and the cumulative deformations after 1 day are -1.117 m, 2.071 m and -0.072 m, respectively. The displacements at station KSMV, the nearest site to the Mw7.9 aftershock in the N, E and U directions, are -0.032 m, 0.742 m and -0.345 m, respectively. The other sites obviously experienced eastern movements and subsidence. The deformation vectors indicate that the horizontal displacements caused by the earthquake point to the epicenter and rupture. Elastic bounds evidently took place at all sites. The results indicate that the crustal movements and earthquake were part of a megathrust caused by the Pacific Plate sinking under the North American Plate to the northeast of Japan island arc.展开更多
Sea surface temperature(SST)retrieved from Advanced Very High Resolution Radiometer(AVHRR)onboard National Oceanic and Atmospheric Administration(NOAA)polar orbiting environmental satellites were validated in the East...Sea surface temperature(SST)retrieved from Advanced Very High Resolution Radiometer(AVHRR)onboard National Oceanic and Atmospheric Administration(NOAA)polar orbiting environmental satellites were validated in the East/Japan Sea(EJS)using surface drifter measurements as ground truths from 2005 to 2010.Overall,the root-mean-square(rms)errors of multichannel SSTs(MCSSTs)and non-linear SSTs(NLSSTs)using global SST coefficients were approximately 0.85℃ and 0.80℃,respectively.An analysis of the SST errors(satellite-drifter)revealed a dependence on the amount of atmospheric moisture.In addition,satellite-derived SSTs tended to be related to wind speeds,particularly during the night.The SST errors also demonstrated diurnal variations with relatively higher rms from 0.80℃ to 1.00℃ during the night than the day,with a small rms of about 0.50℃.Bias also exhibited reasonable diurnal differences,showing small biases during the daytime.Although a satellite zenith angle has been considered in the global SST coefficients,its effect on the SST errors still remained in case of the EJS.Given the diverse use of SST data,the continuous validation and understanding of the characteristic errors of satellite SSTs should be conducted based on extensive in-situ temperature measurements in the global ocean as well as local seas.展开更多
AIM:To elucidate the characteristics of hemorrhagic gastric/duodenal ulcers in a post-earthquake period within one medical district.METHODS:Hemorrhagic gastric/duodenal ulcers in the Iwate Prefectural Kamaishi Hospita...AIM:To elucidate the characteristics of hemorrhagic gastric/duodenal ulcers in a post-earthquake period within one medical district.METHODS:Hemorrhagic gastric/duodenal ulcers in the Iwate Prefectural Kamaishi Hospital during the 6-mo period after the Great East Japan Earthquake Disaster were reviewed retrospectively.The subjects were 27patients who visited our hospital with a chief complaint of hematemesis or hemorrhagic stool and were diagnosed as having hemorrhagic gastric/duodenal ulcers by upper gastrointestinal endoscopy during a 6-mo period starting on March 11,2011.This period was divided into two phases:the acute stress phase,comprising the first month after the earthquake disaster,and the chronic stress phase,from the second through the sixth month.The following items were analyzed according to these phases:age,sex,sites and number of ulcers,peptic ulcer history,status of Helicobacter pylori(H.pylori)infection,intake of non-steroidal anti-inflammatory drugs,and degree of impact of the earthquake disaster.RESULTS:In the acute stress phase from 10 d to 1mo after the disaster,the number of patients increased rapidly,with a nearly equal male-to-female ratio,and the rate of multiple ulcers was significantly higher than in the previous year(88.9%vs 25%,P<0.005).In the chronic stress phase starting 1 mo after the earthquake disaster,the number of patients decreased to a level similar to that of the previous year.There were more male patients during this period,and many patients tended to have a solitary ulcer.All patients with duodenal ulcers found in the acute stress phase were negative for serum H.pylori antibodies,and this was significantly different from the previous year’s positive rate of 75%(P<0.05).CONCLUSION:Severe stress caused by an earthquake disaster may have affected the characteristics of hemorrhagic gastric/duodenal ulcers.展开更多
The flora of the eastern China is the main part of Sino-Japaners floristic region. It shows from the analysis and comparison that the floristic relation of East China with Japan is closer than that with northeast Chin...The flora of the eastern China is the main part of Sino-Japaners floristic region. It shows from the analysis and comparison that the floristic relation of East China with Japan is closer than that with northeast China and Korea. The similarity indices of genera and species of seed plants in the two regions are very high, being 72.6% and 43.3% respectively. The structure and species composition of broad-leaval evergreen forests in the two regions are also similar, and there exist many corresponding communities, such as the forests of Castanopsis carlesii and C. sieboldii. Many plants in East China are conspecific with there in Japan, such as Cercidiphyllum japonicum, Magnolia sieboldii, Nandina domestica etc. Though the genera of Ginkgo, Liriodendron, Sassafras etc. existing now in China are extinct from Japan, their fossils have been discovered from the Tertiary strata in Japan. It seems to indicate that the phytogeographical affinities between East China and Japan are closer in ancient the than it is now, and both of the forest floras originated from the same flora. The flora in Japan did not evolve independently until it separated from Chinese continent and drifted northeastwards in the late period of the Tertiary.展开更多
In contrast to previous studies that have tended to focus on the influence of the total Arctic sea-ice cover on the East Asian summer tripole rainfall pattern, the present study identifies the Barents Sea as the key r...In contrast to previous studies that have tended to focus on the influence of the total Arctic sea-ice cover on the East Asian summer tripole rainfall pattern, the present study identifies the Barents Sea as the key region where the June sea-ice variability exerts the most significant impacts on the East Asian August tripole rainfall pattern, and explores the teleconnection mechanisms involved. The results reveal that a reduction in June sea ice excites anomalous upward air motion due to strong near-surface thermal forcing, which further triggers a meridional overturning wave-like pattern extending to midlatitudes.Anomalous downward motion therefore forms over the Caspian Sea, which in turn induces zonally oriented overturning circulation along the subtropical jet stream, exhibiting the east–west Rossby wave train known as the Silk Road pattern. It is suggested that the Bonin high, a subtropical anticyclone predominant near South Korea, shows a significant anomaly due to the eastward extension of the Silk Road pattern to East Asia. As a possible descending branch of the Hadley cell, the Bonin high anomaly ultimately triggers a meridional overturning, establishing the Pacific–Japan pattern. This in turn induces an anomalous anticyclone and cyclone pair over East Asia, and a tripole vertical convection anomaly meridionally oriented over East Asia. Consequently, a tripole rainfall anomaly pattern is observed over East Asia. Results from numerical experiments using version 5 of the Community Atmosphere Model support the interpretation of this chain of events.展开更多
The present study is based on the sedimentological data from a piston core KCES1 off the southern Ulleung Basin margin,the East Sea(Sea of Japan).The data include sediment color(L^*),X-ray radiographs,grain size ...The present study is based on the sedimentological data from a piston core KCES1 off the southern Ulleung Basin margin,the East Sea(Sea of Japan).The data include sediment color(L^*),X-ray radiographs,grain size distribution and AMS^14C date.Four kinds of sediments(homogeneous,laminated,crudely laminated and hybrid sediments) are identified according to the characters of the sedimentary structures that were considered to reflect changes in bottom-water oxygenation.Alternations of dark laminated/crudely laminated sediments and light homogeneous sediments represent millennial-scale variations that are possibly associated with the high-resolution changes in the East Asian monsoon(EAM).The relative contributions of the East China Sea Coastal Water(ECSCW) and the Tsushima Warm Current(TWC) were likely the main reasons for the repetition of the anoxic and oxic depositional conditions in the East Sea since the last 48 ka BP.During the interstadial,the strengthen summer EAM was attributed to the expansion of the ECSCW because of more humid climate in central Asia,and then more strongly low-salinity,nutrient-enriched water was introduced into the East Sea.The ventilation of deep water was restricted and therefore the dark laminated layer deposited under the anoxic bottom water condition.During the lowest stand of sea level in the last glacial maximum(LGM),the isolated East Sea dominated by stratified water masses and the euxinic depositional environment formed.The homogenous sediments have been predominating since 17.5 ka BP indicating that the TWC has intruded into the East Sea gradually with the stepwise rise of sea level and the bottom water oxygen level was high.During the late Younger Dryas(YD) period,the last dark laminated layer deposited because the ventilation of bottom water was restricted by stronger summer EAM.The TWC strengthened and the bottom water became oxic again from 10.5 ka BP.展开更多
Many studies have revealed that anchovy has exhibited large variability in population size on decadal tim-escales. However, such works concerning anchovy population are mainly based on short historical catch records. ...Many studies have revealed that anchovy has exhibited large variability in population size on decadal tim-escales. However, such works concerning anchovy population are mainly based on short historical catch records. In order to understand the causes of variability in fish stocks (natural and/or anthropogenic) and calibrate the error between catches and standing stocks, it is essential to develop long-term time series of fish stocks from the time when human impacts are minimal or negligible. Well preserved fish scales from sediment record are regarded as useful indicators revealing the history of fish population dynamics over the last centuries. Anchovy scales was first analyzed over the Yellow Sea and East China Sea and the largest abundance was found in the central South Yellow Sea where is regarded as the largest overwintering ground for Japanese anchovy (Engraulis japonicas). Thus in the central South Yellow Sea, two cores covering the last 150 years were collected for estimating fish scale flux. The scale deposition rate (SDR) records show that the decadal scale SDRs were obviously coherent between cores with independent chronologies. Thecalibration of downcore SDRs to the standing stocks of anchovy further validated that SDR is a reliable proxy to recon-struct the long-term anchovy population dynamic in the central South Yellow Sea where anoxic conditions prevail in the sediment. When assembled with other productivity proxies, it would be expected that SDR could be associated with changes in oceanic productivity and may make a contribution to determine the forcing factors and elucidate the mechanism of the process in future.展开更多
<strong>Objective:</strong> The aim of the study is to evaluate the long-term changes in fatigue of cancer patients receiving outpatient chemotherapy after a disaster such as the Great Earthquake. <stro...<strong>Objective:</strong> The aim of the study is to evaluate the long-term changes in fatigue of cancer patients receiving outpatient chemotherapy after a disaster such as the Great Earthquake. <strong>Methods: </strong>From 2012 to 2014, we measured subjective fatigue, autonomic function, and physical activity with reference to the criteria for chronic fatigue syndrome. <strong>Results: </strong>The participants were 13, 9 males (69.2%) and 4 females (30.8%). The most common cancer among the participants was lung cancer 4 patients (30.8%). In 2012, eight patients (61.6%) received anti-cancer drugs and three (23.0%) received the drug by intravenous drip and oral administration. Physical fatigue (p = 0.004), mental fatigue (p = 0.002), comprehensive fatigue (p = 0.012), and comprehensive evaluations (p = 0.032) were significantly different. Significant differences in the autonomic nervous function were observed during the three years from 2012 to 2014 (log LF [p = 0.017], log HF [p = 0.023] and log LF/HF [p = 0.039]). Similar to Subjective fatigue, Significant differences in physical activity were observed during the three years from 2012 to 2014 (DA [p = 0.042], TST [p = 0.037], SE [p = 0.018], AW [p = 0.023] and Naps [p = 0.014]). <strong>Conclusions:</strong> The participants fatigue worsened at one time, but showed improvement over time. In the event of an emergency such as a disaster, it is necessary to evaluate the physical and mental condition based on objective indicators of cancer patients receiving anti-cancer drug treatment and provide nursing support.展开更多
Sea level observed by altimeter during the 1993-2007 period and the thermosteric sea level from 1945 through 2005 obtained by using the global ocean temperature data sets recently published are used to investigate the...Sea level observed by altimeter during the 1993-2007 period and the thermosteric sea level from 1945 through 2005 obtained by using the global ocean temperature data sets recently published are used to investigate the interannual and decadal variability of the sea level in the Japan/East Sea (JES) and its response to E1 Nifio and Southern Oscillation (ENSO). Both the interannual variations of the sea level observed by altimeter and those of the thermosteric sea level obtained from reanalyzed data in the JES are closely related to ENSO. As a result, one important consequence is that the sea level trends are mainly caused by the thermal expansion in the JES. An 'enigma' is revealed that the correlation between the thermosterie sea level and ENSO during the PDO (Pacific Decadal Oscillation) warm phase (post mid-1970s) is inconsistent with that during the cold phase (pre mid-1970s) in the JES. The thermosteric sea level trends and the Southern Oscillation Index (SOI) suggest a strong negative correlation during the period 1977-1998, whereas there appears a relatively weak positive correlation during the period 1945-1976 in the JES. Based on the SODA (Simple Oceanographic Data Assimilation) datasets, possible mechanisms of the interannual and decadal variability of the sea level in the JES are discussed. Comprehensive analysis reveals that the negative anomalies of SOI correspond to the positive anomalies of the southeast wind stress, the net advective heat flux and the sea level in the JES during the PDO warm phase. During the PDO cold phase, the negative anomalies of SOI correspond to the positive anomalies of the southwest wind stress, the negative anomalies of the net advective heat flux and the sea level in the JES.展开更多
Helicobacter pylori (H. pylori) infection is highly prevalent in East Asia. The overallseroprevalence rate of H. pylori infection is 44.2% in China, 37.6%-43.2% in Japan,and 51.0% in South Korea. H. pylori can cause p...Helicobacter pylori (H. pylori) infection is highly prevalent in East Asia. The overallseroprevalence rate of H. pylori infection is 44.2% in China, 37.6%-43.2% in Japan,and 51.0% in South Korea. H. pylori can cause peptic ulcer disease and gastriccancer. East Asian countries have high rates of gastric cancer (age-standardizedincidence rate: 20-30 per 100000). The Kyoto global consensus report emphasizedthat H. pylori gastritis should be considered the main cause for the development ofgastric cancer. H. pylori treatment guidelines in China, Japan, and South Koreahave recently been revised according to data from each of those countries.However, emerging antibiotic resistance is an important barrier to H. pylorieradication. The recommended H. pylori treatment regimens differ among thosethree East Asian countries. In this review, recent guidelines and up-to-dateresearch on H. pylori treatment regimens from China, Japan, and South Korea arediscussed.展开更多
A robust anomalous anticyclonic circulation (AAC) was observed over Northeast Asia and the Japan Sea in boreal win-ter 1997/98 and over the Japan Sea in spring 1998. The formation mechanism is investigated. On the bac...A robust anomalous anticyclonic circulation (AAC) was observed over Northeast Asia and the Japan Sea in boreal win-ter 1997/98 and over the Japan Sea in spring 1998. The formation mechanism is investigated. On the background of the vertically sheared winter monsoonal flow, anomalous rainfall in the tropical Indo-Western Pacific warm pool excited a wave train towards East Asia in the upper troposphere during boreal winter of 1997/98. The AAC over Northeast Asia and the Japan Sea is part of the wave train of equivalent barotropic structure. The AAC over the Japan Sea persisted from winter to spring and even intensified in spring 1998. The diagnostic calculations show that the vorticity and temperature fluxes by synoptic eddies are an important mechanism for the AAC over the Japan Sea in spring 1998.展开更多
The combined effect of the Pacific–Japan (PJ) pattern and Mediterranean–northern Eurasia (MnE) pattern on East Asian surface air temperature (SAT) during summer is investigated using the Japanese 55-year reanalysis ...The combined effect of the Pacific–Japan (PJ) pattern and Mediterranean–northern Eurasia (MnE) pattern on East Asian surface air temperature (SAT) during summer is investigated using the Japanese 55-year reanalysis and Climatic Research Unit SAT data over the period of 1958–2016. The results show that the combination of the two patterns in different phases can result in different SAT anomalies. During the in-phase PJ-MnE years, the overlapping of opposite signs of the atmospheric circulations associated with the PJ and MnE patterns results in weak atmospheric circulation and SAT anomalies in central East Asia;during these years, the significant SAT anomalies are over northern East Asia. In contrast, during the out-of-phase PJ-MnE years, the overlapping of the same signs of the atmospheric circulations associated with the PJ and MnE patterns leads to significant atmospheric circulation and SAT anomalies in central East Asia and northern Asia. The analysis in this study indicates that to better understand and predict the variability of East Asian summer SATs, the combined effect of the PJ and MnE patterns should be taken into account.展开更多
A massive earthquake occurred in the Tohoku and Kanto regions of Japan on the 1 lth of March 2011. In response, a tsunami alert, a tsunami warning and an advisory were issued for the entire Pacific coast region. This ...A massive earthquake occurred in the Tohoku and Kanto regions of Japan on the 1 lth of March 2011. In response, a tsunami alert, a tsunami warning and an advisory were issued for the entire Pacific coast region. This research investigates the evacuation behavior of ships by AIS (automatic identification system) data in Onahama port after the tsunami warning was issued. The unusual behavior observed was attributed to the emergency evacuation of ships. This research investigates the evacuation behaviors of the vessels using the data obtained from AIS, around the Onahama Port during alerting the major tsunami warning. The result shows that most vessels in the port started evacuating approximately 10 min after the major tsunami warning and completed offshore evacuation 40 min after this warning. This contributed in understanding the actual status of the vessel evacuation. In addition, the travel paths of each vessel revealed the influence of the tsunami on the vessels. Furthermore, the exceptional situation where several vessels moved in the same direction at the speed almost same for about 2 hours was confirmed. As a result, it can be estimated that the waves that affected both vessels were the drawback of the tsunamis.展开更多
This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected b...This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected by this disaster as well as for a reduction of the impact of natural disasters that may occur in the future with GIS (geographic information systems) as a social infrastructure positioned at the heart of the information infrastructure. Due to the fact that social media that used ICT (information and communication technology) was useful in the days directly after the disaster, it can be said that it is necessary to investigate the provision of an information infrastructure that uses ICT to reduce the impact of disasters. Therefore, this study proposes the construction of a geographical information database using GIS and the provision and sharing of information using social media GIS after discussion of the relationship between the development of the computerization of Japan and GIS as a valid example of using information systems for recovery and reconstruction after the Great East Japan Earthquake.展开更多
We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(S...We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(SVD) and empirical orthogonal function(EOF). The monthly-mean rainfall data observed at 160 stations in China, monthly-mean sea surface temperature(SST) of the Hadley Center for Climate Prediction and Research and monthly-mean air temperature from the NCEP reanalysis during 1960–2011 were used. Correlation analysis indicates that the SSTAs in the Japan Sea in September may last for three or four months and are an important index for forecasting the winter rainfall and air temperature in NE China. Positive SSTAs in the central Japan Sea and in the sea area east of Tokyo correspond to positive rainfall anomaly and negative air temperature anomaly in NE China. With the rise of SST in the Japan Sea, a weak cyclone appears over the Japan Sea. The northeasterly wind transports water vapor from the Okhotsk to NE China, resulting in more rainfall and lower air temperature. Negative SSTA years are accompanied by warmer air temperature and less snow in NE China. The 1000 h Pa geopotential height anomaly and wind anomaly fields are simulated by IAP-9L model, which supports the analysis results.展开更多
A study of tsunami events in the East (Japan) Sea using continuous Galerkin finite element model, aiming at reproducing tsunami waves generated by underwater earthquakes in 1983 and 1993 respectively has been perfor...A study of tsunami events in the East (Japan) Sea using continuous Galerkin finite element model, aiming at reproducing tsunami waves generated by underwater earthquakes in 1983 and 1993 respectively has been performed focusing on the geographic extent of a topographic feature in the East (Japan) Sea. Numerical models can be the proper tools to study the combined effects of realistic topography. Subsequently, using the FEM based two-dimensional model we have simulated the smoothed and flattened topographic effects by removal of Yamato Rise and seamounts for the cases of tthe 1983 Central region earthquake tsunami and the 1993 southwestern Hokkaido earthquake tsunami. The results have shown that there will be higher tsunamis along the eastern coasts of Korea in general except some areas, like Sokcho with removal of topographic highs, thus providing complicated bottom topography of the East (Japan) Sea as effective tsunami energy scattering.展开更多
基金The Ministry of Land, Transport and Maritime Affairs of Korean Govenment as part of the EAST-I (East Asian Seas Time-series,East/Japan Sea) and OCCAPA (Ocean Chimate Change-Analyses, Projections and Adaptation), through KIOST Project under contract No. PE98742as part of the Development of Technology for CO2 Marine Geological Storage project under contract No. PMS246B
文摘Subinertial fluctuation of a strong northward deep current, which is referred to the Dokdo Abyssal Current (DAC) by Chang et al. (2009), is investigated from current records for about 16.5 and 8.0 months in the Ulle- ung Interplain Gap of the East/lapan Sea. The current below 300 m is bottom-intensified and has nearly depth-independent flow. Near bottom, the spectral peaks of the current were found near 10, 20, and 60 d. The DAC variability near 10 d and 20 d is reasonably consistent with the linear theory of topographic Rossby waves (TRWs) in the following aspects: (1) The motion is columnar and bottom-intensified; (2) the theo- retical cutoff frequency is similar to the observation; (3) The observation-based angles of the wavenumber vector are in good agreement with the theoretical ones. The wavelengths of the TRWs with periods of near 10 d and 20 d near Dokdo are significantly shorter than those with similar timescales in the open oceans (100-250 km). It is primarily due to the weak stratification below 300 m in the East Sea. The deep cur- rent fluctuations with periods of near 10 d and 20 d were accompanied by warm events in the upper layer resulting from eddying processes and/or meandering of the Tsushima Warm Current.
基金The Research Program on Climate Change Adaptation(RECCA)of the Ministry of Education,Culture,Sports,Science and Technology(MEXT)of Japan
文摘In this study the structure and seasonal variations of deep mean circulation in the East/lapan Sea (E/S) were numerically simulated using a mid-resolution ocean general circulation model with two different parameterizations for the eddy-topography interaction (ETI). The strong deep mean circulations observed in the EIS are well reproduced when using the ETI parameterizations. The seasonal variability in the EIS deep layer is shown by using ETI parameterization based on the potential vorticity approach, while it is not shown in the statistical dynamical parameterization. The driving mechanism of the strong deep mean currents in the E/S are discussed by investigating the effects of model grids and parameterizations. The deep mean circulation is more closely related to the baroclinic process and potential vorticity than it is to the wind driven circulation.
基金supported partially by the National Natural Science Foundation of China(No.40974004 and 40974016)the Key Laboratory of Surveying and Mapping Technology on Island and Reef of NASMG,China(No.2011A01)the Key Laboratory of Advanced Surveying Engineering of NASMG,China(No.TJES1101)
文摘Crustal deformation can provide constraints for studying earthquake rupture and shock wave transmission for the Mw9.0 eastern Japan great earthquake. Using the single- epoch precise point positioning (PPP) method and the appropriate positioning flow, we process GPS data from six IGS (International GNSS Service) sites (e.g., MIZU, TSK2, USUD, MTKA, AIRA and KSMV) located in Japan and obtain the positioning results with centimeter scale precision. The displacement time series of the six sites are analyzed using the least squares spectral analysis method to estimate deformations caused by the Mw9.0 mainshock and the Mw7.9 aftershock, and the cumulative displacements after 1 day. Mainshock displacements at station MIZU, the nearest site to the mainshock in the North (N), East (E), and Up (U) directions, are -1.202 m, 2.180 m and -0.104 m, respectively, and the cumulative deformations after 1 day are -1.117 m, 2.071 m and -0.072 m, respectively. The displacements at station KSMV, the nearest site to the Mw7.9 aftershock in the N, E and U directions, are -0.032 m, 0.742 m and -0.345 m, respectively. The other sites obviously experienced eastern movements and subsidence. The deformation vectors indicate that the horizontal displacements caused by the earthquake point to the epicenter and rupture. Elastic bounds evidently took place at all sites. The results indicate that the crustal movements and earthquake were part of a megathrust caused by the Pacific Plate sinking under the North American Plate to the northeast of Japan island arc.
基金This study was supported by Korea Meteorological Administration/National Meteorological Satellite Center and‘Long-term change of structure and function in marine ecosystems of Korea’and‘East Asian Seas Time series-I(EAST-I)’projects funded by the Ministry of Oceans and Fisheries,Korea.
文摘Sea surface temperature(SST)retrieved from Advanced Very High Resolution Radiometer(AVHRR)onboard National Oceanic and Atmospheric Administration(NOAA)polar orbiting environmental satellites were validated in the East/Japan Sea(EJS)using surface drifter measurements as ground truths from 2005 to 2010.Overall,the root-mean-square(rms)errors of multichannel SSTs(MCSSTs)and non-linear SSTs(NLSSTs)using global SST coefficients were approximately 0.85℃ and 0.80℃,respectively.An analysis of the SST errors(satellite-drifter)revealed a dependence on the amount of atmospheric moisture.In addition,satellite-derived SSTs tended to be related to wind speeds,particularly during the night.The SST errors also demonstrated diurnal variations with relatively higher rms from 0.80℃ to 1.00℃ during the night than the day,with a small rms of about 0.50℃.Bias also exhibited reasonable diurnal differences,showing small biases during the daytime.Although a satellite zenith angle has been considered in the global SST coefficients,its effect on the SST errors still remained in case of the EJS.Given the diverse use of SST data,the continuous validation and understanding of the characteristic errors of satellite SSTs should be conducted based on extensive in-situ temperature measurements in the global ocean as well as local seas.
文摘AIM:To elucidate the characteristics of hemorrhagic gastric/duodenal ulcers in a post-earthquake period within one medical district.METHODS:Hemorrhagic gastric/duodenal ulcers in the Iwate Prefectural Kamaishi Hospital during the 6-mo period after the Great East Japan Earthquake Disaster were reviewed retrospectively.The subjects were 27patients who visited our hospital with a chief complaint of hematemesis or hemorrhagic stool and were diagnosed as having hemorrhagic gastric/duodenal ulcers by upper gastrointestinal endoscopy during a 6-mo period starting on March 11,2011.This period was divided into two phases:the acute stress phase,comprising the first month after the earthquake disaster,and the chronic stress phase,from the second through the sixth month.The following items were analyzed according to these phases:age,sex,sites and number of ulcers,peptic ulcer history,status of Helicobacter pylori(H.pylori)infection,intake of non-steroidal anti-inflammatory drugs,and degree of impact of the earthquake disaster.RESULTS:In the acute stress phase from 10 d to 1mo after the disaster,the number of patients increased rapidly,with a nearly equal male-to-female ratio,and the rate of multiple ulcers was significantly higher than in the previous year(88.9%vs 25%,P<0.005).In the chronic stress phase starting 1 mo after the earthquake disaster,the number of patients decreased to a level similar to that of the previous year.There were more male patients during this period,and many patients tended to have a solitary ulcer.All patients with duodenal ulcers found in the acute stress phase were negative for serum H.pylori antibodies,and this was significantly different from the previous year’s positive rate of 75%(P<0.05).CONCLUSION:Severe stress caused by an earthquake disaster may have affected the characteristics of hemorrhagic gastric/duodenal ulcers.
文摘The flora of the eastern China is the main part of Sino-Japaners floristic region. It shows from the analysis and comparison that the floristic relation of East China with Japan is closer than that with northeast China and Korea. The similarity indices of genera and species of seed plants in the two regions are very high, being 72.6% and 43.3% respectively. The structure and species composition of broad-leaval evergreen forests in the two regions are also similar, and there exist many corresponding communities, such as the forests of Castanopsis carlesii and C. sieboldii. Many plants in East China are conspecific with there in Japan, such as Cercidiphyllum japonicum, Magnolia sieboldii, Nandina domestica etc. Though the genera of Ginkgo, Liriodendron, Sassafras etc. existing now in China are extinct from Japan, their fossils have been discovered from the Tertiary strata in Japan. It seems to indicate that the phytogeographical affinities between East China and Japan are closer in ancient the than it is now, and both of the forest floras originated from the same flora. The flora in Japan did not evolve independently until it separated from Chinese continent and drifted northeastwards in the late period of the Tertiary.
基金supported by the National Key R&D Program of China(Grant No.2016YFA0600703)the National Natural Science Foundation of China(Grant Nos.41605059,41505073 and 41375083)+1 种基金the Young Talent Support Program of the China Association for Science and Technology(Grant No.2016QNRC001)the Research Council of Norway SNOWGLACE(244166/E10)project
文摘In contrast to previous studies that have tended to focus on the influence of the total Arctic sea-ice cover on the East Asian summer tripole rainfall pattern, the present study identifies the Barents Sea as the key region where the June sea-ice variability exerts the most significant impacts on the East Asian August tripole rainfall pattern, and explores the teleconnection mechanisms involved. The results reveal that a reduction in June sea ice excites anomalous upward air motion due to strong near-surface thermal forcing, which further triggers a meridional overturning wave-like pattern extending to midlatitudes.Anomalous downward motion therefore forms over the Caspian Sea, which in turn induces zonally oriented overturning circulation along the subtropical jet stream, exhibiting the east–west Rossby wave train known as the Silk Road pattern. It is suggested that the Bonin high, a subtropical anticyclone predominant near South Korea, shows a significant anomaly due to the eastward extension of the Silk Road pattern to East Asia. As a possible descending branch of the Hadley cell, the Bonin high anomaly ultimately triggers a meridional overturning, establishing the Pacific–Japan pattern. This in turn induces an anomalous anticyclone and cyclone pair over East Asia, and a tripole vertical convection anomaly meridionally oriented over East Asia. Consequently, a tripole rainfall anomaly pattern is observed over East Asia. Results from numerical experiments using version 5 of the Community Atmosphere Model support the interpretation of this chain of events.
基金The National Natural Science Foundation of China under contract Nos 40431002,40606016 and 40710069004the China-Korea joint research programme and the Primary Science Foundation of First Institute of Oceanography under contract No. 2007T09
文摘The present study is based on the sedimentological data from a piston core KCES1 off the southern Ulleung Basin margin,the East Sea(Sea of Japan).The data include sediment color(L^*),X-ray radiographs,grain size distribution and AMS^14C date.Four kinds of sediments(homogeneous,laminated,crudely laminated and hybrid sediments) are identified according to the characters of the sedimentary structures that were considered to reflect changes in bottom-water oxygenation.Alternations of dark laminated/crudely laminated sediments and light homogeneous sediments represent millennial-scale variations that are possibly associated with the high-resolution changes in the East Asian monsoon(EAM).The relative contributions of the East China Sea Coastal Water(ECSCW) and the Tsushima Warm Current(TWC) were likely the main reasons for the repetition of the anoxic and oxic depositional conditions in the East Sea since the last 48 ka BP.During the interstadial,the strengthen summer EAM was attributed to the expansion of the ECSCW because of more humid climate in central Asia,and then more strongly low-salinity,nutrient-enriched water was introduced into the East Sea.The ventilation of deep water was restricted and therefore the dark laminated layer deposited under the anoxic bottom water condition.During the lowest stand of sea level in the last glacial maximum(LGM),the isolated East Sea dominated by stratified water masses and the euxinic depositional environment formed.The homogenous sediments have been predominating since 17.5 ka BP indicating that the TWC has intruded into the East Sea gradually with the stepwise rise of sea level and the bottom water oxygen level was high.During the late Younger Dryas(YD) period,the last dark laminated layer deposited because the ventilation of bottom water was restricted by stronger summer EAM.The TWC strengthened and the bottom water became oxic again from 10.5 ka BP.
基金The National Basic Research Program of China under contract Nos 2010CB428902 and 2006CB400007the National Natural Science Foundation of China under contract No.40876088
文摘Many studies have revealed that anchovy has exhibited large variability in population size on decadal tim-escales. However, such works concerning anchovy population are mainly based on short historical catch records. In order to understand the causes of variability in fish stocks (natural and/or anthropogenic) and calibrate the error between catches and standing stocks, it is essential to develop long-term time series of fish stocks from the time when human impacts are minimal or negligible. Well preserved fish scales from sediment record are regarded as useful indicators revealing the history of fish population dynamics over the last centuries. Anchovy scales was first analyzed over the Yellow Sea and East China Sea and the largest abundance was found in the central South Yellow Sea where is regarded as the largest overwintering ground for Japanese anchovy (Engraulis japonicas). Thus in the central South Yellow Sea, two cores covering the last 150 years were collected for estimating fish scale flux. The scale deposition rate (SDR) records show that the decadal scale SDRs were obviously coherent between cores with independent chronologies. Thecalibration of downcore SDRs to the standing stocks of anchovy further validated that SDR is a reliable proxy to recon-struct the long-term anchovy population dynamic in the central South Yellow Sea where anoxic conditions prevail in the sediment. When assembled with other productivity proxies, it would be expected that SDR could be associated with changes in oceanic productivity and may make a contribution to determine the forcing factors and elucidate the mechanism of the process in future.
文摘<strong>Objective:</strong> The aim of the study is to evaluate the long-term changes in fatigue of cancer patients receiving outpatient chemotherapy after a disaster such as the Great Earthquake. <strong>Methods: </strong>From 2012 to 2014, we measured subjective fatigue, autonomic function, and physical activity with reference to the criteria for chronic fatigue syndrome. <strong>Results: </strong>The participants were 13, 9 males (69.2%) and 4 females (30.8%). The most common cancer among the participants was lung cancer 4 patients (30.8%). In 2012, eight patients (61.6%) received anti-cancer drugs and three (23.0%) received the drug by intravenous drip and oral administration. Physical fatigue (p = 0.004), mental fatigue (p = 0.002), comprehensive fatigue (p = 0.012), and comprehensive evaluations (p = 0.032) were significantly different. Significant differences in the autonomic nervous function were observed during the three years from 2012 to 2014 (log LF [p = 0.017], log HF [p = 0.023] and log LF/HF [p = 0.039]). Similar to Subjective fatigue, Significant differences in physical activity were observed during the three years from 2012 to 2014 (DA [p = 0.042], TST [p = 0.037], SE [p = 0.018], AW [p = 0.023] and Naps [p = 0.014]). <strong>Conclusions:</strong> The participants fatigue worsened at one time, but showed improvement over time. In the event of an emergency such as a disaster, it is necessary to evaluate the physical and mental condition based on objective indicators of cancer patients receiving anti-cancer drug treatment and provide nursing support.
基金supported by the National Basic Research Program of China under Grant No. 973-2007CB- 411807
文摘Sea level observed by altimeter during the 1993-2007 period and the thermosteric sea level from 1945 through 2005 obtained by using the global ocean temperature data sets recently published are used to investigate the interannual and decadal variability of the sea level in the Japan/East Sea (JES) and its response to E1 Nifio and Southern Oscillation (ENSO). Both the interannual variations of the sea level observed by altimeter and those of the thermosteric sea level obtained from reanalyzed data in the JES are closely related to ENSO. As a result, one important consequence is that the sea level trends are mainly caused by the thermal expansion in the JES. An 'enigma' is revealed that the correlation between the thermosterie sea level and ENSO during the PDO (Pacific Decadal Oscillation) warm phase (post mid-1970s) is inconsistent with that during the cold phase (pre mid-1970s) in the JES. The thermosteric sea level trends and the Southern Oscillation Index (SOI) suggest a strong negative correlation during the period 1977-1998, whereas there appears a relatively weak positive correlation during the period 1945-1976 in the JES. Based on the SODA (Simple Oceanographic Data Assimilation) datasets, possible mechanisms of the interannual and decadal variability of the sea level in the JES are discussed. Comprehensive analysis reveals that the negative anomalies of SOI correspond to the positive anomalies of the southeast wind stress, the net advective heat flux and the sea level in the JES during the PDO warm phase. During the PDO cold phase, the negative anomalies of SOI correspond to the positive anomalies of the southwest wind stress, the negative anomalies of the net advective heat flux and the sea level in the JES.
基金Supported by the Soonchunhyang University Research Fund,No. 10210061
文摘Helicobacter pylori (H. pylori) infection is highly prevalent in East Asia. The overallseroprevalence rate of H. pylori infection is 44.2% in China, 37.6%-43.2% in Japan,and 51.0% in South Korea. H. pylori can cause peptic ulcer disease and gastriccancer. East Asian countries have high rates of gastric cancer (age-standardizedincidence rate: 20-30 per 100000). The Kyoto global consensus report emphasizedthat H. pylori gastritis should be considered the main cause for the development ofgastric cancer. H. pylori treatment guidelines in China, Japan, and South Koreahave recently been revised according to data from each of those countries.However, emerging antibiotic resistance is an important barrier to H. pylorieradication. The recommended H. pylori treatment regimens differ among thosethree East Asian countries. In this review, recent guidelines and up-to-dateresearch on H. pylori treatment regimens from China, Japan, and South Korea arediscussed.
基金supported by the Ministry of Science and Technology of China(National Basic Research Program of China(Grant No.2012CB955602))the National Key Program for Developing Basic Science(Grant No.2010CB428904)the Natural Science Foundation of China(Grant Nos.40830106,40921004,41176006)
文摘A robust anomalous anticyclonic circulation (AAC) was observed over Northeast Asia and the Japan Sea in boreal win-ter 1997/98 and over the Japan Sea in spring 1998. The formation mechanism is investigated. On the background of the vertically sheared winter monsoonal flow, anomalous rainfall in the tropical Indo-Western Pacific warm pool excited a wave train towards East Asia in the upper troposphere during boreal winter of 1997/98. The AAC over Northeast Asia and the Japan Sea is part of the wave train of equivalent barotropic structure. The AAC over the Japan Sea persisted from winter to spring and even intensified in spring 1998. The diagnostic calculations show that the vorticity and temperature fluxes by synoptic eddies are an important mechanism for the AAC over the Japan Sea in spring 1998.
基金jointly supported by the National Natural Science Foundation of China [grant numbers 41522503 and 41421004]
文摘The combined effect of the Pacific–Japan (PJ) pattern and Mediterranean–northern Eurasia (MnE) pattern on East Asian surface air temperature (SAT) during summer is investigated using the Japanese 55-year reanalysis and Climatic Research Unit SAT data over the period of 1958–2016. The results show that the combination of the two patterns in different phases can result in different SAT anomalies. During the in-phase PJ-MnE years, the overlapping of opposite signs of the atmospheric circulations associated with the PJ and MnE patterns results in weak atmospheric circulation and SAT anomalies in central East Asia;during these years, the significant SAT anomalies are over northern East Asia. In contrast, during the out-of-phase PJ-MnE years, the overlapping of the same signs of the atmospheric circulations associated with the PJ and MnE patterns leads to significant atmospheric circulation and SAT anomalies in central East Asia and northern Asia. The analysis in this study indicates that to better understand and predict the variability of East Asian summer SATs, the combined effect of the PJ and MnE patterns should be taken into account.
文摘A massive earthquake occurred in the Tohoku and Kanto regions of Japan on the 1 lth of March 2011. In response, a tsunami alert, a tsunami warning and an advisory were issued for the entire Pacific coast region. This research investigates the evacuation behavior of ships by AIS (automatic identification system) data in Onahama port after the tsunami warning was issued. The unusual behavior observed was attributed to the emergency evacuation of ships. This research investigates the evacuation behaviors of the vessels using the data obtained from AIS, around the Onahama Port during alerting the major tsunami warning. The result shows that most vessels in the port started evacuating approximately 10 min after the major tsunami warning and completed offshore evacuation 40 min after this warning. This contributed in understanding the actual status of the vessel evacuation. In addition, the travel paths of each vessel revealed the influence of the tsunami on the vessels. Furthermore, the exceptional situation where several vessels moved in the same direction at the speed almost same for about 2 hours was confirmed. As a result, it can be estimated that the waves that affected both vessels were the drawback of the tsunamis.
文摘This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected by this disaster as well as for a reduction of the impact of natural disasters that may occur in the future with GIS (geographic information systems) as a social infrastructure positioned at the heart of the information infrastructure. Due to the fact that social media that used ICT (information and communication technology) was useful in the days directly after the disaster, it can be said that it is necessary to investigate the provision of an information infrastructure that uses ICT to reduce the impact of disasters. Therefore, this study proposes the construction of a geographical information database using GIS and the provision and sharing of information using social media GIS after discussion of the relationship between the development of the computerization of Japan and GIS as a valid example of using information systems for recovery and reconstruction after the Great East Japan Earthquake.
基金supported by Innovation and Research Foundation of Ocean University of China(No.201261009)the National Natural Science Foundation of China(Nos.40930844 and 10735030)the National Basic Research Program of China(the 973 Program)under grant No.2005CB422 301
文摘We studied the impact of sea surface temperature anomaly(SSTA) in the Japan Sea and the sea area east of Japan on the winter rainfall and air temperature in Northeast(NE) China using the singular value decomposition(SVD) and empirical orthogonal function(EOF). The monthly-mean rainfall data observed at 160 stations in China, monthly-mean sea surface temperature(SST) of the Hadley Center for Climate Prediction and Research and monthly-mean air temperature from the NCEP reanalysis during 1960–2011 were used. Correlation analysis indicates that the SSTAs in the Japan Sea in September may last for three or four months and are an important index for forecasting the winter rainfall and air temperature in NE China. Positive SSTAs in the central Japan Sea and in the sea area east of Tokyo correspond to positive rainfall anomaly and negative air temperature anomaly in NE China. With the rise of SST in the Japan Sea, a weak cyclone appears over the Japan Sea. The northeasterly wind transports water vapor from the Okhotsk to NE China, resulting in more rainfall and lower air temperature. Negative SSTA years are accompanied by warmer air temperature and less snow in NE China. The 1000 h Pa geopotential height anomaly and wind anomaly fields are simulated by IAP-9L model, which supports the analysis results.
基金The work was financially supported by the Korean Ministry of Land,Transport and Maritime AffairsINTAS(Grant No.06-1000013-9236)
文摘A study of tsunami events in the East (Japan) Sea using continuous Galerkin finite element model, aiming at reproducing tsunami waves generated by underwater earthquakes in 1983 and 1993 respectively has been performed focusing on the geographic extent of a topographic feature in the East (Japan) Sea. Numerical models can be the proper tools to study the combined effects of realistic topography. Subsequently, using the FEM based two-dimensional model we have simulated the smoothed and flattened topographic effects by removal of Yamato Rise and seamounts for the cases of tthe 1983 Central region earthquake tsunami and the 1993 southwestern Hokkaido earthquake tsunami. The results have shown that there will be higher tsunamis along the eastern coasts of Korea in general except some areas, like Sokcho with removal of topographic highs, thus providing complicated bottom topography of the East (Japan) Sea as effective tsunami energy scattering.