By using a two-dimensional Full Implicit Continuous Eulerian (FICE) scheme and taking the atmospheric basic motion equations as the governing equations, a numerical model for nonlinear propagation of Acoustic Gravity Wave (AGW) disturbance in two-dimensional polar coordinates is solved. Results of numerical simulation show that the AGW packets propagate steadily upward and keep its shape well after several periods. This shows that FICE scheme is reliable for simulating the nonlinear propagation of AGW disturbance in a two-dimensional compressible atmosphere. The response of middle and upper atmosphere to the pulse disturbance of lower atmosphere in background winds or without background winds is simulated by using this model, and obtain the distribution of a certain physical quantity in time and space from earth's surface to 300 km above. The results reveal that the response of ionosphere occurs at a large horizontal distance from the source and the disturbance becomes greater with increasing of height. The situation when the direction of the background wind is opposite to or the same as the direction of disturbed velocity of gravity-wave is studied. The results show that gravity wave propagating against winds is easier than those propagating along winds and the background wind can accelerate gravity wave propagation. Just upon the source, an acoustic wave component with period of 6min can be found. These images of simulation are similar to observations of the Total Electron Content (TEC) disturbances caused by the great Sumatra-Andaman earthquake on December 26 in 2004.
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