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Internal Dynamics of the Generation of Atmospheric Teleconnection Patterns
Li Zhijin,Ji Liren,
Li Zhijin
,Ji Liren

大气科学进展 , 1996,
Abstract: A preferred growing perturbation concept has been introduced into the dynamical study on the generation of atmospheric teleconnection patterns. It is shown that all the important teleconnection patterns observed in the real atmosphere may be established through internal barotropic dynamical processes
Difference of the Atmospheric Teleconnection Patterns between Winter and Summer over the Northern Hemisphere and Its Relation with the Air Temperature Fields

CHEN Fangli,LI Weibiao,

大气科学 , 2009,
Abstract: The different features of the atmospheric teleconnection patterns between winter and summer over the Northern Hemisphere(NH) and their relations with the air temperature fields are studied using the 55 years NCEP/NCAR reanalysis data.It is found that there are obvious differences in the routes of the atmospheric teleconnection between winter and summer over the NH.The teleconnection route in winter exhibits meridional features while the teleconnection route is noticeably zonal in summer.Results also show th...
Atmospheric teleconnection patterns and eddy kinetic energy content: wavelet analysis
V. N. Khokhlov, A. V. Glushkov,I. A. Tsenenko
Nonlinear Processes in Geophysics (NPG) , 2004,
Abstract: In this paper, we employ a non-decimated wavelet decomposition to analyse long-term variations of the teleconnection pattern monthly indices (the North Atlantic Oscillation and the Southern Oscillation) and the relationship of these variations with eddy kinetic energy contents (KE) in the atmosphere of mid-latitudes and tropics. Major advantage of using this tool is to isolate short- and long-term components of fluctuations. Such analysis allows revealing basic periodic behaviours for the North Atlantic Oscillations (NAO) indices such as the 4-8-year and the natural change of dominant phase. The main results can be posed as follows. First, if the phases of North Atlantic and Southern Oscillations vary synchronously with the 4-8-year period then the relationship between the variations of the NAO indices and the KE contents is the most appreciable. Second, if the NAO phase tends to abrupt changes then the impact of these variations on the eddy kinetic energy contents in both mid-latitudes and tropics is more significant than for the durational dominance of certain phase.
How well do state-of-the-art atmosphere-ocean general circulation models reproduce atmospheric teleconnection patterns?
D?rthe Handorf,Klaus Dethloff
Tellus A , 2012, DOI: 10.3402/tellusa.v64i0.19777
Abstract: This article evaluates the ability of state-of-the-art climate models to reproduce the low-frequency variability of the mid-tropospheric winter flow of the Northern Hemisphere in terms of atmospheric teleconnection patterns. Therefore, multi-model simulations for present-day conditions, performed for the 4th assessment report of the Intergovernmental Panel on Climate Change, have been analysed and compared with re-analysis data sets. The spatial patterns of atmospheric teleconnections are reproduced reasonably by most of the models. The comparison of coupled with atmosphere-only runs confirmed that a better representation of the forcing by sea surface temperatures has the potential to slightly improve the representation of only wave train-like patterns. Due to internally generated climate variability, the models are not able to reproduce the observed temporal behaviour. Insights into the dynamical reasons for the limited skill of climate models in reproducing teleconnections have been obtained by studying the relation between major teleconnections and zonal wind variability patterns. About half of the models are able to reproduce the observed relationship. For these cases, the quality of simulated teleconnection patterns is largely determined by the quality of zonal wind variability patterns. Therefore, improvements of simulated eddy-mean flow interaction have the potential to improve the atmospheric teleconnections.
Summertime Atmospheric Teleconnection Pattern Associated with a Warming over the Eastern Tibetan Plateau

ZHU Weijun,Yongsheng ZHANG,

大气科学进展 , 2009,
Abstract: By using a surface air temperature index (SATI) averaged over the eastern Tibetan Plateau (TP), investigation is conducted on the short-term climate variation associated with the interannual air warming (or cooling) over the TP in each summer month. Evidence suggests that the SATI is associated with a consistent teleconnection pattern extending from the TP to central-western Asia and southeastern Europe. Associated rainfall changes include, for a warming case, a drought in northern India in May and June, and a stronger mei-yu front in June. The latter is due to an intensified upper-level northeasterly in eastern China and a wetter and warmer condition over the eastern TP. In the East Asian regions, the time-space distributions of the correlation patterns between SATI and rainfall are more complex and exhibit large differences from month to month. Some studies have revealed a close relationship between the anomalous heating over the TP and the rainfall anomaly along the Yangtze River valley appearing in the summer on a seasonal mean time-scale, whereas in the present study, this relationship only appears in June and the signal's significance becomes weaker after the long-term trend in the data was excluded. Close correlations between SATI and the convection activity and SST also occur in the western Pacific in July and August: A zonally-elongated warm tone in the SST in the northwestern Pacific seems to be a passive response of the associated circulation related to a warm SATI. The SATI-associated teleconnection pattern provides a scenario consistently linking the broad summer rainfall anomalies in Europe, central-western Asia, India, and East Asia.
K Gambo,Lu Li,Li Weijing,
K. Gambo
,Lu Li,Li Weijing

大气科学进展 , 1987,
Abstract: In this paper, the anomaly of disturbance height field over Northern Hemisphere due to SST anomaly in the tropical Atlantic Ocean is simulated by using the general circulation model of IAP. A quasi-geostrophic, 34-level spherical coordinate model is also used to compute the distribution of atmospheric circulation anomaly when there is an anomaly of heat source over the tropical Atlantic. The computed results show that, owing to the heat source anomaly over the tropical Atlantic, the EU-pattern anomaly in the winter circulation may be caused. Namely, a ridge will be enhanced over the northwest Europe, a trough will be deepened over Siberia, but a positive anomaly of disturbance height field will be formed over the northeast China, Japan and other areas of East Asia. Moreover, the numerically simulated results show that the above-mentioned EU-pattern anomalies of circulation are due to the propagations of planetary wave train. About 15 days after an anomaly of the beat source over the tropical Atlantic is injected, the EU-pattern anomaly of atmospheric circulation is formed. This is in good agreement with the results analysed theoretically.
An Inter-hemispheric Teleconnection and a Possible Mechanism for Its Formation
LIU Ge,JI Liren,SUN Shuqing,ZHANG Qingyun,
,JI Liren,SUN Shuqing,ZHANG Qingyun

大气科学进展 , 2010,
Abstract: Through observational analyses, an inter-hemispheric teleconnection is identified between the subtropical region of the South China Sea to the western Pacific near the Philippines (WP) and the region to the east of Australia (AE). The teleconnection is significantly correlated with sea surface temperature anomalies (SSTAs) in key sea areas (including the Indian Ocean, the South China Sea, and the area to the east of Australia). Based on the IAP T42L9 model, numerical experiments are performed to explore a possible mechanism for the formation of the teleconnection. The results show that the positive SST anomalies in the key sea areas may jointly contribute to the occurrence and maintenance of the positive geopotential height anomalies over both the WP and AE and be a critical factor in the teleconnection formation. The large-scale SST anomaly in the Indian Ocean, involving the tropics and subtropics of both hemispheres, may lead to concurrent atmospheric responses over both the WP and AE, while the effect of the local SST anomaly to the east of Australia seems to reinforce and maintain the positive height anomaly over the AE.
Atmospheric $ν$ and Long Baseline $ν$ experiments II  [PDF]
Giorgio Giacomelli
Physics , 2011,
Abstract: A short introduction summarizes the experimental high energy field of neutrino oscillations and the oscillation notations. Then the results obtained by experiments on atmospheric neutrino oscillations are summarized and discussed. At the beginning of the new century a number of long baseline neutrino beams became available. The results obtained by different long baseline neutrino oscillation experiments are considered, including the first possible event $\nu_{\mu} \rightarrow \nu_{\tau}$ in appearance mode. Finally conclusions and perspectives are discussed.
Teleconnection Patterns in the Northern Hemisphere Simulated by IAP GCM
Teleconnection Paterns in the Northern Hemisphere Simulated by IAP GCM

Xue Feng,Zeng Qingcun,
Xue Feng
,Zeng Qingcun

大气科学进展 , 1997,
Abstract: Based on monthly mean sea level pressure and 500 hPa height data for a 20-year period simulated by IAP 2L AGCM, teleconnection patterns in the Northern Hemisphere appearing in the model are identified and compared with observations. The results show that almost all of the observed teleconnection patterns in the Northern winter can be reproduced by the model, thus these patterns exist in the atmosphere without any external anomalies. On the other hand, the simulated teleconnection patterns are more dependent on each other than the observed, i.e., they are lack of spatial orthogonality among them, therefore, it is possible that more complex patterns will appear under the action of anomalous external factors. Besides, the simulated teleconnection patterns in summer are greatly different from those in winter, in particular, its scale in summer is much less than that in winter
Teleconnection Pattern between the Arctic Ice Area and the 500 hPa Geopotential Height Field during the Northern Hemispheric Summer

Fang Zhifang,Tan Youbang,Sui Xuehai,

大气科学 , 1991,
Abstract: In this paper, the correlation field between the Arctic ice area and 500 hPa geopotential height field, the one-point correlation maps at 500 hPa, and the 1000-500 hPa thickness difference chart between the strongest arctic ice year and the weakest year for July and August (etc.)are analyzed.According to the foregoing statistical discussion, it may be noted: the arctic ice cold source in summer can be forcing the teleconnection pattern in the northern hemispheric atmosphere. The teleconnection pattern has two-dimensional Rossby wave train and equivalent barotropic structure.The centers of action in the teleconnection pattern can across the westerly jet and into the subtropics, but they only exist in the westerly belt.The teleconnectin pattern effects the atmospheric circulation and weather showing the polar ice being excessive, the polar low pressure being stengthened, the Canada ridge and the Northern American trough being strengthened too, and vice versa.
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