太阳风向磁层-电离层(Magnetosphere and Ionosphere,MI)系统输入能量,而输入的能量随后在MI系统中消耗.本文从能量守恒原理出发,讨论太阳风-磁层-电离层(SMI)耦合过程中的能流路径和能量收支的定量关系.主要讨论9个问题:(1)太阳风向MI...太阳风向磁层-电离层(Magnetosphere and Ionosphere,MI)系统输入能量,而输入的能量随后在MI系统中消耗.本文从能量守恒原理出发,讨论太阳风-磁层-电离层(SMI)耦合过程中的能流路径和能量收支的定量关系.主要讨论9个问题:(1)太阳风向MI系统的能量输入,(2)MI系统对能量输入的响应,(3)环电流的能量消耗,(4)极区电离层焦耳加热的能量消耗,(5)极光粒子沉降的能量消耗,(6)磁尾能量的消耗、储存以及返回下游太阳风,(7)平静期间的能量积累与释放,(8)能量在不同能汇中的分配,(9)评价能量函数的准则和方法.展开更多
This paper presents a brief summary of our recent work based on global MHD simulations of the Solar wind-Magnetosphere-Ionosphere (SMI) system with emphasis on the electrodynamic coupling in the system.The main conclu...This paper presents a brief summary of our recent work based on global MHD simulations of the Solar wind-Magnetosphere-Ionosphere (SMI) system with emphasis on the electrodynamic coupling in the system.The main conclusions obtained are summarized as follows.(1) As a main dynamo of the SMI system,the bow shock contributes to both region 1 Field-Aligned Current (FAC) and cross-tail current.Under strong interplanetary driving conditions and moderate Alfv'en Mach numbers,the bow shock's contribution may exceed more than fifty percent of the total of either region 1 or cross-tail currents.(2) In terms of more than 100 simulation runs with due southward Interplanetary Magnetic Field (IMF),we have found a combined parameter f=E sw P sw M A -1/2 (E sw,P sw,and M A are the solar wind electric field,ram pressure,and Alfv'en Mach number,respectively):both the ionospheric transpolar potential and the magnetopause reconnection voltage vary linearly with f for small f,but saturate for large f.(3) The reconnection voltage is approximately fitted by sin 3/2 (θ IMF /2),where θ IMF is the IMF clock angle.The ionospheric transpolar potential,the voltage along the polar cap boundary,and the electric fields along the merging line however defined they may be,respond differently to θ IMF,so it is not justified to take them as substitutes for the reconnection voltage.展开更多
文摘太阳风向磁层-电离层(Magnetosphere and Ionosphere,MI)系统输入能量,而输入的能量随后在MI系统中消耗.本文从能量守恒原理出发,讨论太阳风-磁层-电离层(SMI)耦合过程中的能流路径和能量收支的定量关系.主要讨论9个问题:(1)太阳风向MI系统的能量输入,(2)MI系统对能量输入的响应,(3)环电流的能量消耗,(4)极区电离层焦耳加热的能量消耗,(5)极光粒子沉降的能量消耗,(6)磁尾能量的消耗、储存以及返回下游太阳风,(7)平静期间的能量积累与释放,(8)能量在不同能汇中的分配,(9)评价能量函数的准则和方法.
基金Supported by grants NNSFC (40831060,40621003)NKBRSF G2006CB806304 in China
文摘This paper presents a brief summary of our recent work based on global MHD simulations of the Solar wind-Magnetosphere-Ionosphere (SMI) system with emphasis on the electrodynamic coupling in the system.The main conclusions obtained are summarized as follows.(1) As a main dynamo of the SMI system,the bow shock contributes to both region 1 Field-Aligned Current (FAC) and cross-tail current.Under strong interplanetary driving conditions and moderate Alfv'en Mach numbers,the bow shock's contribution may exceed more than fifty percent of the total of either region 1 or cross-tail currents.(2) In terms of more than 100 simulation runs with due southward Interplanetary Magnetic Field (IMF),we have found a combined parameter f=E sw P sw M A -1/2 (E sw,P sw,and M A are the solar wind electric field,ram pressure,and Alfv'en Mach number,respectively):both the ionospheric transpolar potential and the magnetopause reconnection voltage vary linearly with f for small f,but saturate for large f.(3) The reconnection voltage is approximately fitted by sin 3/2 (θ IMF /2),where θ IMF is the IMF clock angle.The ionospheric transpolar potential,the voltage along the polar cap boundary,and the electric fields along the merging line however defined they may be,respond differently to θ IMF,so it is not justified to take them as substitutes for the reconnection voltage.
