The dynamics of eastward shifting cyclonic vortices are investigated in terms of a barotropic primitive equation model, and six experiments are performed. Both the interaction of a cyclonic vortex with vorticity lumps...The dynamics of eastward shifting cyclonic vortices are investigated in terms of a barotropic primitive equation model, and six experiments are performed. Both the interaction of a cyclonic vortex with vorticity lumps and the interaction of the vortex with the shearing basic flow may induce the strengthening of the vortex in a short period, however, the vortex intensity still shows a general decreasing tendency over the whole integration time period. The interaction among the shearing basic flow, cyclonic vortex, and multiple vorticity lumps can change the tendency. The merging of the cyclonic vortex with vorticity lumps in the shearing basic flow of positive vorticity is directly responsible for the maintenance and development of the cyclonic vortex.展开更多
Based on multiple datasets, correlation and composite analyses, and case studies, this paper investigated possible influences of the Indian Ocean dipole(IOD) mode on the eastward propagation of intraseasonal oscillati...Based on multiple datasets, correlation and composite analyses, and case studies, this paper investigated possible influences of the Indian Ocean dipole(IOD) mode on the eastward propagation of intraseasonal oscillation in the tropical atmosphere. The results showed that(1) the 30-60 day outgoing longwave radiation anomalies in the southeastern Indian Ocean and the 30-60 day 850-hPa zonal wind anomalies over the equatorial central Indian Ocean were significantly correlated with the IOD index;(2) during positive IOD years, the anomalously cold water in the southeastern Indian Ocean and the 850-hPa anomalous easterlies over the equatorial central Indian Ocean might act as barriers to the continuously eastward propagation of the intraseasonal convection, which interrupts the Madden-Julian oscillation(MJO) propagation in the eastern equatorial Indian Ocean and western Pacific; and(3) during negative IOD years, the anomalously warm water in the southeastern Indian Ocean and the low-level westerly anomalies over the equatorial central Indian Ocean favor the eastward movement of MJO.展开更多
Northward propagation in summer and eastward propagation in winter are two distinguished features of tropical intraseasonal oscillation （TISO） over the equatorial Indian Ocean. According to numerical modeling result...Northward propagation in summer and eastward propagation in winter are two distinguished features of tropical intraseasonal oscillation （TISO） over the equatorial Indian Ocean. According to numerical modeling results, under a global warming scenario, both propagations were intensified. The enhanced northward propagation in summer can be attributed to the enhanced atmosphere-ocean interaction and the strengthened mean southerly wind; and the intensified eastward propagation in winter is associated with the enhanced convection-wind coupling process and the strengthened equatorial Kevin wave. Future changes of TISO propagations need to be explored in more climate models.展开更多
At 8:30 on October 27, the first international flight from Shanghai to Singapore MU576 took off at Pudong Airport. Thus,all international flights and those to Hong Kong and Macao were all moved to Pudong Airport. Besi...At 8:30 on October 27, the first international flight from Shanghai to Singapore MU576 took off at Pudong Airport. Thus,all international flights and those to Hong Kong and Macao were all moved to Pudong Airport. Besides internationalflights and Hong Kong and Macao flights, the eastward moving also cover some domestic flights, namely flights fromSanya, Haikou, Guangzhou, Shenzhen, Zhuhai, Qingdao, Yantai, Weihai, Weifang and so on in Northwest China, Mid-South China,and East China to Shanghai. After the eastward moving, the flight distribution at two airports in Shanghai changed greatly.展开更多
The“Eastward Migration Festival”is an emerging festival initiated by Yugur scholars,with the collective participation of the masses,and held in some areas of the Yugur,now held four times.As it carries the collectiv...The“Eastward Migration Festival”is an emerging festival initiated by Yugur scholars,with the collective participation of the masses,and held in some areas of the Yugur,now held four times.As it carries the collective heritage of the Yugur people,the“Eastward Migration Festival”draws on Pierre Nora’s theory of“Les Lieux de Memoire”,and explains why the“Eastward Migration Festival”activity has become the“Les Lieux de Memoire”of Yugur society from three aspects:history,symbol and narrative.展开更多
基金the National Natural Science Foundation under Grant No.49775263the project of the Tibetan Plateau Experiment(TIPEX)of Atmospheric Science and the 973 Project onheavy rain in China.
文摘The dynamics of eastward shifting cyclonic vortices are investigated in terms of a barotropic primitive equation model, and six experiments are performed. Both the interaction of a cyclonic vortex with vorticity lumps and the interaction of the vortex with the shearing basic flow may induce the strengthening of the vortex in a short period, however, the vortex intensity still shows a general decreasing tendency over the whole integration time period. The interaction among the shearing basic flow, cyclonic vortex, and multiple vorticity lumps can change the tendency. The merging of the cyclonic vortex with vorticity lumps in the shearing basic flow of positive vorticity is directly responsible for the maintenance and development of the cyclonic vortex.
基金National Science foundation of China(41005038)Chinese Public Sector(Meteorology)Research and Special Project(GYHY200906016)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2009BAC51B01,2009BAC51B02)
文摘Based on multiple datasets, correlation and composite analyses, and case studies, this paper investigated possible influences of the Indian Ocean dipole(IOD) mode on the eastward propagation of intraseasonal oscillation in the tropical atmosphere. The results showed that(1) the 30-60 day outgoing longwave radiation anomalies in the southeastern Indian Ocean and the 30-60 day 850-hPa zonal wind anomalies over the equatorial central Indian Ocean were significantly correlated with the IOD index;(2) during positive IOD years, the anomalously cold water in the southeastern Indian Ocean and the 850-hPa anomalous easterlies over the equatorial central Indian Ocean might act as barriers to the continuously eastward propagation of the intraseasonal convection, which interrupts the Madden-Julian oscillation(MJO) propagation in the eastern equatorial Indian Ocean and western Pacific; and(3) during negative IOD years, the anomalously warm water in the southeastern Indian Ocean and the low-level westerly anomalies over the equatorial central Indian Ocean favor the eastward movement of MJO.
基金supported by the "973" projects (Grant Nos. 2012CB417203,2012CB955400,and 2013CB955803) "863" project (Grant No.2010AA012305)NSFC (Grant Nos. 41005036 and 41023002)
文摘Northward propagation in summer and eastward propagation in winter are two distinguished features of tropical intraseasonal oscillation （TISO） over the equatorial Indian Ocean. According to numerical modeling results, under a global warming scenario, both propagations were intensified. The enhanced northward propagation in summer can be attributed to the enhanced atmosphere-ocean interaction and the strengthened mean southerly wind; and the intensified eastward propagation in winter is associated with the enhanced convection-wind coupling process and the strengthened equatorial Kevin wave. Future changes of TISO propagations need to be explored in more climate models.
文摘At 8:30 on October 27, the first international flight from Shanghai to Singapore MU576 took off at Pudong Airport. Thus,all international flights and those to Hong Kong and Macao were all moved to Pudong Airport. Besides internationalflights and Hong Kong and Macao flights, the eastward moving also cover some domestic flights, namely flights fromSanya, Haikou, Guangzhou, Shenzhen, Zhuhai, Qingdao, Yantai, Weihai, Weifang and so on in Northwest China, Mid-South China,and East China to Shanghai. After the eastward moving, the flight distribution at two airports in Shanghai changed greatly.
基金This essay is an achievement of the project“Graduate Research and Innovation Project”(Yxm 2019002)funded by Northwest Minzu University,China。
文摘The“Eastward Migration Festival”is an emerging festival initiated by Yugur scholars,with the collective participation of the masses,and held in some areas of the Yugur,now held four times.As it carries the collective heritage of the Yugur people,the“Eastward Migration Festival”draws on Pierre Nora’s theory of“Les Lieux de Memoire”,and explains why the“Eastward Migration Festival”activity has become the“Les Lieux de Memoire”of Yugur society from three aspects:history,symbol and narrative.
