The synoptic variation of the atmospheric radio refractive index, evaluated from standard weather observations, is examin ed d uri ng an ou t break of polar continental air. It is found t hat t he reduced-t o-sea-Ieve1 value of t he r efractive index is a more sensitive synoptic parameter t han t he station value. The reduced valu e is quite sensit ive to the humidity and density structure of t...

Analysis of observational data suggests two-way interactions between the tropical intraseasonal oscillation (ISO) and synoptic-scale variability (SSV). On one hand, SSV is strongly modulated by the ISO; that is, a strengthened (weakened) SSV appears during the enhanced (suppressed) ISO phase. The northwest– southeast-oriented synoptic wave train is strengthened and well organized in the northwe...

The development mechanism of synoptic-scale disturbances over the tropical western North Pacific (WNP) associated with boreal summer intraseasonal oscillation (BSISO) under different phases interannual Pacific-Japan (PJ) pattern is investigated. Intraseasonal convection enhanced widely WNP for BSISO 5-7 in positive PJ years, when seasonal-mean convective activity enhanced. By contrast, develope...

A large wide-field telescope and camera with optical throughput over 200 m deg – a factor of 50 beyond what we currently have – would enable the detection of faint moving or bursting optical objects: from Earth threatening asteroids to energetic events at the edge of the optical universe. An optimized design for LSST is a 8.4 m telescope with a 3 degree field of view and an optical throughput o...

This paper has the finality of describe climatology of extratropical cyclones, anticyclones and storm tracks for the NH and SH. There is a long history of studies on the characteristics of synoptic systems, beginning with classical work on mid-latitude cyclones. For the SH, analyses of pressure data provide extensive statistics of the climatology of synoptic systems. Interestingly, the anticycl...

abstract in recent years, dust storm in western part of iran, especially fars province, caused various problems for people. the aim of this research is the identification of circulation patterns producing dust storms over fars province. for this purpose, firstly the code number 6 of current weather at 12 gmt belongs to 8 synoptic stations during the statistical period of 1992-2003 has been extr...

Abstract Tropical precipitation and circulation are often coupled span a vast spectrum of scales from few to several thousands kilometers hours weeks. Current operational numerical weather prediction (NWP) models struggle with representing the full range tropical phenomena. Synoptic planetary particular importance because improved skill in representation larger-scale features such as convective...

The effect of the advection of magnetic features on synoptic frames has been estimated and it shows that for the time interval ranging from 4 to 14 days the differential rotation of magnetic features accounts for most of the surface transport of photospheric magnetic fields. It is shown that both the 1996.08.27 19:12:30 synoptic frame with the effect of differential rotation included and the fo...

[1] In this paper, by using a dynamic model with synoptic eddy and low-frequency flow (SELF) interaction, we show that the SELF feedback is of significant importance for the formation of the AO/NAO in both winter and summer. Although background storm activity is significantly weaker in summer than that in winter, the positive SELF feedback associated with the AO/NAO mode in summer can be as str...