在強烈磁暴發生時，地球磁層顯現出一種不尋常以及非線性的狀態，例如顯著的晨昏方向的不對稱性，極冠區的電位飽和現象以及磁重聯飽和現象。針對這些現象特性的模型預測與判斷可以是一個兼顧實驗與理論研究的主題。我們認為，磁層內部因磁暴所引發的全球性電流系統的增強可能造成了上述的這些飽和效應，而這些飽和效應也有可能為另一個原因造成，那就是發生在磁層邊界層及磁層頂的一些物理過程。而藉由全球性的磁流體模擬，我們可以區分磁層內部與外部的物理過程。在本研究中，磁暴發生時的地磁觀測資料、磁層邊界層之觀測資料以及船首震波之觀測資料將與我們藉由磁流體經驗模式(例如Tsyganenko模式)得到的預測來加以比較。這些比較結果將可以告訴我們哪一種主要的物理過程與機制造成了磁層中的非線性飽和效應。 During strong magnetic storms, the Earth’s magnetosphere exhibits unusual and nonlinear behavior such as prominent dawn-dusk asymmetry, saturation of polar cap potential and reconnection saturation. Model representation and determination of nature of these phenomena is a subject of extensive experimental and theoretical studies. These effects might result from either internal processes, related to substantial storm-time intensification of the global magnetospheric current system, or from external processes in the magnetosheath and at the magnetospheric boundary, magnetopause. Global MHD simulation provides a unique opportunity to distinguish between those processes. Comparison of experimental data on storm-time geomagnetic field and magnetospheric boundaries, magnetopause and bow shock, with predictions of the MHD and empirical models (such as such as Tsyganenko model etc.) allows revealing those physical phenomena which are responsible for the non-linear saturation effects in the magnetosphere 研究期間：10008 ~ 10107
