To comprehensively understand the Arctic and Antarctic upper atmosphere, it is often crucial to analyze various data that are obtained from many regions. Infrastructure that promotes such interdisciplinary studies on ...To comprehensively understand the Arctic and Antarctic upper atmosphere, it is often crucial to analyze various data that are obtained from many regions. Infrastructure that promotes such interdisciplinary studies on the upper atmosphere has been developed by a Japanese inter-university project called the Inter-university Upper atmosphere Global Observation Network （1UGONET）. The objective of this paper is to describe the infrastructure and tools developed by IUGONET. We focus on the data analysis software. It is written in Interactive Data Language （IDL） and is a plug-in for the THEMIS Data Analysis Software suite （TDAS）, which is a set of IDL libraries used to visualize and analyze satellite- and ground-based data. We present plots of upper atmospheric data provided by IUGONET as examples of applications, and verify the usefulness of the software in the study of polar science. We discuss IUGONET＇s new and unique developments, i.e., an executable file of TDAS that can run on the IDL Virtual Machine, IDL routines to retrieve metadata from the IUGONET database, and an archive of 3-D simulation data that uses the Common Data Format so that it can easily be used with TDAS.展开更多
We performed three dimensional resistive magnetohydrodynamic simulations to study the magnetic reconnection using an initially shearing magnetic field configuration（force free field with a current sheet in the middle...We performed three dimensional resistive magnetohydrodynamic simulations to study the magnetic reconnection using an initially shearing magnetic field configuration（force free field with a current sheet in the middle of the computational box）.It is shown that there are two types of reconnection jets：the ordinary reconnection jets and fan-shaped jets,which are formed along the guide magnetic field.The fan-shaped jets are significantly different from the ordinary reconnection jets which are ejected by magnetic tension force.There are two driving forces for accelerating the fan-shaped jets.One is the Lorentz force which initially dominates the motion of fluid elements,and then the gas pressure gradient force accelerates the fluid elements in the later stage.The dependence on magnetic reconnection angle and resistivity value has also been studied.The formation and evolution of these jets provide a new understanding of dynamic magnetohydrodynamic jets.展开更多
基金supported by the Special Edu-cational Research Budget(Research Promotion)[FY2009]the Special Budget(Project)[FY2010 and later years]from the Ministry of Education,Culture,Sports,Science and Technology(MEXT),Japansupported by the GRENE Arctic Climate Change Research Project,Japan
文摘To comprehensively understand the Arctic and Antarctic upper atmosphere, it is often crucial to analyze various data that are obtained from many regions. Infrastructure that promotes such interdisciplinary studies on the upper atmosphere has been developed by a Japanese inter-university project called the Inter-university Upper atmosphere Global Observation Network （1UGONET）. The objective of this paper is to describe the infrastructure and tools developed by IUGONET. We focus on the data analysis software. It is written in Interactive Data Language （IDL） and is a plug-in for the THEMIS Data Analysis Software suite （TDAS）, which is a set of IDL libraries used to visualize and analyze satellite- and ground-based data. We present plots of upper atmospheric data provided by IUGONET as examples of applications, and verify the usefulness of the software in the study of polar science. We discuss IUGONET＇s new and unique developments, i.e., an executable file of TDAS that can run on the IDL Virtual Machine, IDL routines to retrieve metadata from the IUGONET database, and an archive of 3-D simulation data that uses the Common Data Format so that it can easily be used with TDAS.
基金Supported by the National Natural Science Foundation of China (NSFC,Grant Nos. 10878002,10610099,10933003 and10673004)a grant from the National Basic Research Program of China (973 project,No. 2011CB811402)+1 种基金support and under the auspices of the NIFS Collaboration Research program (NIFS07KTBL005)performed with the KDK system of the Research Institute for Sustainable Humanosphere (RISH) at Kyoto University, as a collaborative research project
文摘We performed three dimensional resistive magnetohydrodynamic simulations to study the magnetic reconnection using an initially shearing magnetic field configuration（force free field with a current sheet in the middle of the computational box）.It is shown that there are two types of reconnection jets：the ordinary reconnection jets and fan-shaped jets,which are formed along the guide magnetic field.The fan-shaped jets are significantly different from the ordinary reconnection jets which are ejected by magnetic tension force.There are two driving forces for accelerating the fan-shaped jets.One is the Lorentz force which initially dominates the motion of fluid elements,and then the gas pressure gradient force accelerates the fluid elements in the later stage.The dependence on magnetic reconnection angle and resistivity value has also been studied.The formation and evolution of these jets provide a new understanding of dynamic magnetohydrodynamic jets.
