Authors: Mei Hong Ren Zhang Feng Xue Kefeng Liu
Publish Date: 2009/10/07
Volume: 30, Issue: 10, Pages: 1263-
Abstract
To analyze the dynamic mechanism of unusual activities of the subtropical high the spacetime varible separation of the partial differential vortex equations is carried out with Galerkin methods based on the heat force and the whirl movement dissipation effect Aiming at the subjective and manmade conventional method of choice in the space basis functions we propose to combine the empirical orthogonal function EOF analysis with the genetic algorithm to inverse the space basis functions from the actual sequence of fields A group of trigonometric functions are chosen as a generalized space basis function With the leastsquares error of the basis function and EOF typical fields and with the complete orthogonality of basis functions we can get the dualbound function A genetic algorithm is then introduced to carry out surface fitting and coefficient optimization of the basis function As a result the objective and reasonable constant differential equation of the subtropical high is obtained by inversion Finally based on the obtained nonlinear dynamics model the dynamic behavior and mechanism of the subtropical high is analyzed and discussed under the influence of heat force We find that solar radiation and zonal differences in land and sea are important factors impacting the potential field and flow field changes of the subtropical areas These factors lead to strength changes of the subtropical high and mediumterm advance/retreat activities The former is a gradual change while the latter shows more break characteristics Meaningful results are obtained in the analysis
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