Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar...Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar region.After the onset of a December WPV event,the dynamic processes influencing Eurasian temperature can be split into two separate periods.Period I(lag of 0-25 days)is referred to as the stratosphere-troposphere interactions period,as it is mainly characterized by stratospheric signals propagating downwards.In Period I,a stratospheric negative Northern Annular Mode(NAM)pattern associated with the WPV propagates downwards,inducing a negative NAM in the troposphere.The anomalous low centers over the Mediterranean and North Pacific bring cold advection to northern Eurasia,resulting in a north-cold-south-warm dipole pattern over Eurasia.The zero line between negative and positive temperature anomalies moves southwards during days 5-20.Stratospheric cold anomalies at midlatitudes propagate downwards to high latitudes in the troposphere and contribute to the dipole structure.During PeriodⅡ(lag of 25-40 days),as downward signals from the stratosphere have vanished,the dynamic processes mainly take place within the troposphere.Specifically,a wave train is initiated from the North Atlantic region to northern Europe.The propagation of wave activity flux intensifies a cyclonic anomaly over northern Europe,which brings cold advection to Scandinavia and warm advection to central Asia.Therefore,a northwest-cold-southeast-warm dipole structure occupies Eurasia and migrates southeastwards during this period.展开更多
Illustration All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in ...Illustration All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.展开更多
Following an assessment by our editorial committee, with input given by our language services company, we have appointed additional experts as NRR reviewers during December 2009 December 2010. We wish to thank these n...Following an assessment by our editorial committee, with input given by our language services company, we have appointed additional experts as NRR reviewers during December 2009 December 2010. We wish to thank these new reviewers, and our long-term reviewers, in advance for their objective, fair and timely contributions in the coming year.展开更多
A sound scientific understanding of the factors affecting the environment is essential to guarantee the sustainable development of the world＇s economic and societal activities. Many environmental issues,such as air q...A sound scientific understanding of the factors affecting the environment is essential to guarantee the sustainable development of the world＇s economic and societal activities. Many environmental issues,such as air quality and climate展开更多
All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chi- nese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near Chi...All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chi- nese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.展开更多
Illustration All the data in this catalog are chosen from the ″Preliminary Seismological Report of Chi-nese Seismic Stations″ (Its abbreviation is ″Monthly Report″). The catalog includes the events of M≥4.7 in an...Illustration All the data in this catalog are chosen from the ″Preliminary Seismological Report of Chi-nese Seismic Stations″ (Its abbreviation is ″Monthly Report″). The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ″Monthly Report″ is monthly compiled展开更多
The European Union summit ended on December 16 in Madrid. European leaders set their seal on a drive to make Europe a global power ready for challenges of the next century with a new currency and a new list of members...The European Union summit ended on December 16 in Madrid. European leaders set their seal on a drive to make Europe a global power ready for challenges of the next century with a new currency and a new list of members. The US federal government partially shut down for the second time in a month on December 16, with President Bill展开更多
1. Systems Engineering 01 Systems Engineering and Its Theoretical Basis, Yu Jingyuan, Beijing Institute of Information and Control, July 1989, pp.1-12. This article provides an overview of the architecture of system s...1. Systems Engineering 01 Systems Engineering and Its Theoretical Basis, Yu Jingyuan, Beijing Institute of Information and Control, July 1989, pp.1-12. This article provides an overview of the architecture of system science developed by Qian Xuesen, with a particular stress laid upon the methodology and theoretical basis of systems engineering. The latter refers mainly to the establishment of systematology. Presented here is an introduction to some conclusions on the object, content and method of systematology展开更多
Russian President Boris Yeltsin arrived in Beijing on December 17 on a visit to China. Speaking to reporters at Beijing airport upon arrival, Yeltsin said it is only natural that Russia and China, which share a 4000-k...Russian President Boris Yeltsin arrived in Beijing on December 17 on a visit to China. Speaking to reporters at Beijing airport upon arrival, Yeltsin said it is only natural that Russia and China, which share a 4000-kilometre border, should seek to develop their friendship and co-operation. Yeltsin and Chinese President Yang Shangkun signed the joint declaration on the basic principles governing bilateral relations in Beijing on December 18 after separate talks in the morning between Yeltsin and Chinese Premier Li Peng and Communist Party General Secretary Jiang Zemin.展开更多
The spatial distribution of December temperature in Pakistan has been assessed by statistical method based on mean monthly data from 51 ground stations. The analysis is performed at decadal scale over the period of 19...The spatial distribution of December temperature in Pakistan has been assessed by statistical method based on mean monthly data from 51 ground stations. The analysis is performed at decadal scale over the period of 1950-2000. December is one of the representative months of winter season in Pakistan, the country with subtropical location and complex rugged terrains, plateaus and plains. The results support a slight rising temperature trend in December. However, this change in temperature varies from region to region as well as from decade to decade and reflects a complicated spatial-temporal structure of temperature anomalies. The assessment shows that the temperature anomalies in different national territories at local scale do not follow the assumption that winter months are warming in northern hemisphere. Both the isothermal shift and temperature anomalies confirm that the mountainous areas of Pakistan face more temperature variability than plains.展开更多
French films with Chinese (and sometimes English) subtitles Tickets: RMB 20 (Students: RMB 10) Fidelity card: RMB 100/5 films + 1 free (Students: RMB 50) Cinema, Institut Fran ais de Chine More information on activiti...French films with Chinese (and sometimes English) subtitles Tickets: RMB 20 (Students: RMB 10) Fidelity card: RMB 100/5 films + 1 free (Students: RMB 50) Cinema, Institut Fran ais de Chine More information on activities: www.institutfran-cais-chine.展开更多
基金supported by the National Natural Science Foundation of China [grant numbers 41730964,41575079,and 41421004]
文摘Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar region.After the onset of a December WPV event,the dynamic processes influencing Eurasian temperature can be split into two separate periods.Period I(lag of 0-25 days)is referred to as the stratosphere-troposphere interactions period,as it is mainly characterized by stratospheric signals propagating downwards.In Period I,a stratospheric negative Northern Annular Mode(NAM)pattern associated with the WPV propagates downwards,inducing a negative NAM in the troposphere.The anomalous low centers over the Mediterranean and North Pacific bring cold advection to northern Eurasia,resulting in a north-cold-south-warm dipole pattern over Eurasia.The zero line between negative and positive temperature anomalies moves southwards during days 5-20.Stratospheric cold anomalies at midlatitudes propagate downwards to high latitudes in the troposphere and contribute to the dipole structure.During PeriodⅡ(lag of 25-40 days),as downward signals from the stratosphere have vanished,the dynamic processes mainly take place within the troposphere.Specifically,a wave train is initiated from the North Atlantic region to northern Europe.The propagation of wave activity flux intensifies a cyclonic anomaly over northern Europe,which brings cold advection to Scandinavia and warm advection to central Asia.Therefore,a northwest-cold-southeast-warm dipole structure occupies Eurasia and migrates southeastwards during this period.
文摘Illustration All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.
文摘Following an assessment by our editorial committee, with input given by our language services company, we have appointed additional experts as NRR reviewers during December 2009 December 2010. We wish to thank these new reviewers, and our long-term reviewers, in advance for their objective, fair and timely contributions in the coming year.
文摘A sound scientific understanding of the factors affecting the environment is essential to guarantee the sustainable development of the world＇s economic and societal activities. Many environmental issues,such as air quality and climate
文摘All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chi- nese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.
文摘Illustration All the data in this catalog are chosen from the ″Preliminary Seismological Report of Chi-nese Seismic Stations″ (Its abbreviation is ″Monthly Report″). The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ″Monthly Report″ is monthly compiled
文摘The European Union summit ended on December 16 in Madrid. European leaders set their seal on a drive to make Europe a global power ready for challenges of the next century with a new currency and a new list of members. The US federal government partially shut down for the second time in a month on December 16, with President Bill
文摘1. Systems Engineering 01 Systems Engineering and Its Theoretical Basis, Yu Jingyuan, Beijing Institute of Information and Control, July 1989, pp.1-12. This article provides an overview of the architecture of system science developed by Qian Xuesen, with a particular stress laid upon the methodology and theoretical basis of systems engineering. The latter refers mainly to the establishment of systematology. Presented here is an introduction to some conclusions on the object, content and method of systematology
文摘Russian President Boris Yeltsin arrived in Beijing on December 17 on a visit to China. Speaking to reporters at Beijing airport upon arrival, Yeltsin said it is only natural that Russia and China, which share a 4000-kilometre border, should seek to develop their friendship and co-operation. Yeltsin and Chinese President Yang Shangkun signed the joint declaration on the basic principles governing bilateral relations in Beijing on December 18 after separate talks in the morning between Yeltsin and Chinese Premier Li Peng and Communist Party General Secretary Jiang Zemin.
文摘The spatial distribution of December temperature in Pakistan has been assessed by statistical method based on mean monthly data from 51 ground stations. The analysis is performed at decadal scale over the period of 1950-2000. December is one of the representative months of winter season in Pakistan, the country with subtropical location and complex rugged terrains, plateaus and plains. The results support a slight rising temperature trend in December. However, this change in temperature varies from region to region as well as from decade to decade and reflects a complicated spatial-temporal structure of temperature anomalies. The assessment shows that the temperature anomalies in different national territories at local scale do not follow the assumption that winter months are warming in northern hemisphere. Both the isothermal shift and temperature anomalies confirm that the mountainous areas of Pakistan face more temperature variability than plains.
文摘French films with Chinese (and sometimes English) subtitles Tickets: RMB 20 (Students: RMB 10) Fidelity card: RMB 100/5 films + 1 free (Students: RMB 50) Cinema, Institut Fran ais de Chine More information on activities: www.institutfran-cais-chine.
