Preliminary Study on Relationship between Clustering Activity of Tibetan Plateau Vortex and 10～30 day Low\|Frequency Oscillations
Updatetime：2010-11-26From：
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The researacher Zhang Pengfei etc. recently statistically annalyzed the temporal\|spatial locations and frequencis of Tibetan Plateau (TP) Vortex occurred from May to September 1998 and 2003, the clustering activity periods of TP Vortex in 1998 and 2003 have been determined, 500 hPa relative vorticity and 10～30 day low\|frequency oscillation (LFO) of OLR are discussed also. The results show that the occurrence of TP Vortex is of clustering activity feature and periodicity. The nine active periods of TP Vortex are closly associated with 10～30 day and 30～60 day LFOs. The most of TP Vortex developed in the positive phase (cyclone) of 10~30 day LFO and negative phase (convection) of convective disturbance. All nine active periods of TP Vortex are corresponding to the cyclonic phase of 10～30 day oscillations. The 10～30 day positive vorticity turbulence provided the cyclonic vortictiy dynamics condition for development and maintenance of TP Vortex to make for the frequently development of TP vortex in positive phase of turbulence. It is found that the 10～30 day oscillations of relative vorticity of atmosphere are of improtant modulation action for clustering activity of TP Vortex. The convective phase of 10～30 day oscillations of convective activity in TP is to take the clustering activity of TP Vortex as main character. TP Vortex repeatedly and continuously develops in convective phase to make for the active development of convective disturbance.
issued by <<Plateau Meteorology>>
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