近代日本“东洋学”的成立及其性质功能

近代日本的"东洋学"是亚洲区域研究的综合性学科,它主要是站在日本立场上研究亚洲,其中既有文献整理、注释、踏查、考古、考据等较为客观的学术研究,更与日本的近代战略、国力、国策、时局密切相关,具有强烈的时代性与国家主义性质。日本东洋学的根本功能,是在"东洋—西洋""东洋—日本"的二元结构中进行文化上的认同和辨异。它认同东洋文化即亚洲各国的连带性,同时又强调日本文化特殊论与日本优越论,沉溺于日本民族的自我赞美,直接间接地为日本主导东洋、成为东洋"盟主"制造学术理论依据。

Recent Climate Warming of Central China Reflected by Temperature-sensitive Tree Growth in the Eastern Qinling Mountains and its Linkages to the Pacific and Atlantic Oceans

We have developed a 202-year tree-ring width chronology of Shensi fir(Abies chensiensis) growing in an open canopy forest at the treeline of the eastern Qinling Mountains. Climate response analyses revealed that the ring width of Shensi fir trees is primarily controlled by the range of temperature from February–June. The regression model that we used for statistical temperature reconstruction passed the leave-one-out cross-validation used in dendroclimatology, resulting in a quality-controlled February–June reconstruction for the eastern Qinling Mountains. The model accounts for 36.7% of the instrumental temperature variance during the period of 1960–2012. Warm springs and early summers occurred during AD 1870–1873, 1909–1914, 1927–1958 and 1997–2012, while the periods of AD 1874–1908, 1915–1926 and 1959–1996 were relatively cold. Spatial climate correlation analyses with gridded land surface data revealed that our temperature reconstruction contains a strong regional temperature signal for central China. The linkages of ourtemperature reconstruction with sea surface temperature in the Atlantic and Pacific oceans suggest the connection of regional temperature variations to large-scale ocean–atmosphere–land circulation. Preliminary analysis of links between large-scale climatic variation and the temperature reconstruction also shows that there is a relationship between extremes in spring and early summer temperature and anomalous atmospheric circulation in the Qinling Mountains. Overall, our study provides reliable information for the research of past temperature variability in the Qinling Mountains, China.

Distribution of the tropical Pacific surface zonal wind anomaly and its relation with two types of El Nio

E1 Nino events with an eastern Pacific pattern （EP） and central Pacific pattern （CP） were first separated using rotated empirical orthogonal functions （REOF）. Lead/lag regression and rotated singular value decomposition （RSVD） analyses were then carried out to study the relation between the surface zonal wind （SZW） anomalies and sea surface temperature （SST） anomalies in the tropical Pacific. A possible physical process for the CP E1 Nifio was proposed. For the EP E1 Nino, strong westerly anomalies that spread eastward continuously produce an anomalous ocean zonal convergence zone （ZCZ） centered on about 165°W. This SZW anomaly pattern favors poleward and eastward Sverdrup transport at the equator. For the CP E1Nino, westerly anomalies and the ZCZ are mainly confined to the western Pacific, and easterly anomalies blow in the eastern Pacific. This SZW anomaly pattern restrains poleward and eastward Sverdrup transport at the equator; however, there is an eastward Sverdrup transport at about 5°N, which favors the wanning of the north-eastern tropical Pacific. It is found that the slowness of eastward propagation of subsurface warm water （partly from the downwelling caused by Ekman convergence and the ZCZ） is due to the slowdown of the undercurrent in the central basin, and vertical advection in the central Pacific may be important in the formation and disappearance of the CP E1 Nifio.

Equatorward shift of annual Rossby waves in the Equatorial Pacific Ocean

Annual Rossby wave is a key component of the ENSO phenomenon in the equatorial Pacific Ocean. Due to the paucity and seasonal bias in historical hydrographic data,previous studies on equatorial Rossby waves only gave qualitative description. The accumulation of Argo measurements in recent years has greatly alleviated the data problem. In this study,seasonal variation of the equatorial Pacific Ocean is examined with annual harmonic analysis of Argo gridded data. Results show that strong seasonal signal is present in the western equatorial Pacific and explains more than 50% of the thermal variance below 500 m. Lag-correlation tracing further shows that this sub-thermocline seasonal signal originates from the eastern equatorial Pacific via downward and southwestward propagation of annual Rossby waves. Possible mechanisms for the equatorward shift of Rossby wave path are also discussed.

Variation in joint mode of the tropical Indian-Pacific Ocean thermodynamic anomaly

Previous research has defined the index of the Indian-Pacific thermodynamic anomaly joint mode (IPTAJM) and suggested that the winter IPTAJM has an important impact on summer rainfall over China. However, the possible causes for the interannual and decadal variability of the IPTAJM are still unclear. Therefore, this work investigates zonal displacements of both the western Pacific warm pool (WPWP) and the eastern Indian Ocean warm pool (EIOWP). The relationships between the WPWP and the EIOWP and the IPTAJM are each examined, and then the impacts of the zonal wind anomalies over the equatorial Pacific and Indian Oceans on the IPTAJM are studied. The WPWP eastern edge anomaly displays significant interannual and decadal variability and experienced a regime shift in about 1976 and 1998, whereas the EIOWP western edge exhibits only distinct interannual variability. The decadal variability of the IPTAJM may be mainly caused by both the zonal migration of the WPWP and the 850 hPa zonal wind anomaly over the central equatorial Pacific. On the other hand, the zonal migrations of both the WPWP and the EIOWP and the zonal wind anomalies over the central equatorial Pacific and the eastern equatorial Indian Ocean may be all responsible for the interannual variability of the IPTAJM.

Change in Spring Meridional Circulation and Its Relation to Summer Typhoon Activities

This study documents the decadal changes of the spring meridional circulation （SMC） over 110°E- 165°E and the relationship between the SMC and summer （June-July-August-September） typhoon activity over the Western North Pacific （WNP） during 1948-2010. The authors found that the SMC was changed after 1969. Before its change, the SMC had no clear relation with the summer typhoon number over the WNP （TNWNP）, but after the change, it has become positively correlated with the TNWNP, with a correlation coefficient of 0.57 be- tween them （above the 99% confidence level）. It was ob- served that after the SMC was changed, the positive tropical sea surface temperature anomaly associated with the SMC was shifted from the Equatorial Eastern Pacific （El Nifio） to the equatorial middle Pacific （El Nifio Mo- doki）; at the same time, the Pacific decadal oscillation （PDO） pattern over the North Pacific, which is associated with the SMC, was enhanced. The SMC and the TNWNP are both modulated by the E1 Nifio Modoki after 1969, so the relationship between them becomes significant.

西田哲学的东西方文化观及日本文化论

西田几多郎从“东洋的无”出发建构哲学体系,他把核心概念“纯粹经验”和“场所”界定为主客统一、身心一如的“绝对的无”,并作为唯一的实在,又把“绝对矛盾的自己同一的自己限定”作为其“场所的逻辑”,在此基础上阐述了他的东洋(东方)观及日本文化论,认为东西方文化的根本差异在于究竟是把“有”作为实在还是把“无”作为实在。而作为东洋文化的日本文化贯彻了东洋的“绝对无”,在“行为的直观”中不断改变又保持统一,其鲜明表现就是“情”的艺术的文化。将东西方文化观及日本文化论予以哲学化的表述,是西田对于日本的东方学思想史的独特贡献。

Using CMIP5 model outputs to investigate the initial errors that cause the “spring predictability barrier” for El Nio events

Most ocean-atmosphere coupled models have difficulty in predicting the E1 Nifio-Southern Oscillation （ENSO） when starting from the boreal spring season. However, the cause of this spring predictability barrier （SPB） phenomenon remains elusive. We investigated the spatial characteristics of optimal initial errors that cause a significant SPB for E1 Nifio events by using the monthly mean data of the pre-industrial （PI） control runs from several models in CMIP5 experiments. The results indicated that the SPB-related optimal initial errors often present an SST pattern with positive errors in the central-eastern equatorial Pa- cific, and a subsurface temperature pattern with positive errors in the upper layers of the eastern equatorial Pacific, and nega- tive errors in the lower layers of the western equatorial Pacific. The SPB-related optimal initial errors exhibit a typical La Ni- fia-like evolving mode, ultimately causing a large but negative prediction error of the Nifio-3.4 SST anomalies for El Nifio events. The negative prediction errors were found to originate from the lower layers of the western equatorial Pacific and then grow to be large in the eastern equatorial Pacific. It is therefore reasonable to suggest that the E1 Nifio predictions may be most sensitive to the initial errors of temperature in the subsurface layers of the western equatorial Pacific and the Nifio-3.4 region, thus possibly representing sensitive areas for adaptive observation. That is, if additional observations were to be preferentially deployed in these two regions, it might be possible to avoid large prediction errors for E1 Nifio and generate a better forecast than one based on additional observations targeted elsewhere. Moreover, we also confirmed that the SPB-related optimal initial errors bear a strong resemblance to the optimal precursory disturbance for E1 Nifio and La Nifia events. This indicated that im- provement of the observation network by additional observations in the identified sensitive areas would also be helpful in de- tecting the signals provided by the precursory disturbance, which may greatly improve the ENSO prediction skill.