我國華衛一號(現已更名為福衛一號)上的電離層電漿電動效應儀，自1999年起，已觀測五年多在電離層頂部的離子資料。透過這豐富的資料庫，我們已建立隨時間、季節與太陽週期變化的全球離子溫度分布。在 2006 年，我們曾探究午後時段離子溫度脊之觀測結果。在此之前，從未在文獻上有看到此一現象。但在那時候，我們沒有模式可進行精細的研究。僅能用相關之觀測資料進行粗略的解釋，認為氧離子的絕熱壓縮是其主因。近日我們已學會如何正確地使用與改良 SAMI2 模式，並可產生模式資料來與現有的離子觀測資料做比對。此外，我們會使用 HINOTORI 衛星的電子溫度量測，來驗證我們的推論與 SAMI2 模式的正確性。透過一系列的比較，我們希望能進一步改良 SAMI2 模式，使其能釐清產生午後時段離子溫度脊之物理機制。Ion temperature has been measured with the Ionospheric Plasma and Electrodynamics Instrument (IPEI) onboard the first satellite of Republic of China (ROCSAT-1) at 600 km altitude for 5.3 years. Global distributions of ion temperature have been constructed and investigated for different local times, seasons and solar variability. In 2006, we have published an article to describe the variations of the temperature crests in the afternoon sector. Such temperature crests in the afternoon sector were not shown in the literature before. However, we can only suspect the adiabatic compression of the field-aligned plasma flow to produce such distributions but cannot make exact conclusions about it. Right now we can play SAMI2 model very well and it is time to investigate the possible causes with it. Furthermore, electron temperature distribution from HINOTORI satellite would also be used to check the correctness of the SAMI2 model and our explanation. We hope that this study can help improve the SAMI2 model and clarify the physical mechanisms to produce the temperature crests in the afternoon sector. 研究期間 : 9808 ~ 9907
