%0 Journal Article
%T TheoriesandSimulationsinSubstormResearch:AReview
%A R.
%A A.
%A Wolf
%J 空间科学学报
%P 125-149
%D 2011
%X Boththeoryandsimulationhaveplayedimportantrolesindefiningandilluminatingthekeymechanismsinvolvedinsubstorms.Basictheoriesofmagneticreconnectionandofinterchangeandballooninginstabilitiesweredevelopedmorethan50yearsago,andtheseplasmaphysicalconceptshavebeencentralindiscussionsofsubstormphysics.Avastamountofresearchonreconnection,includingboththeoreticalandcomputationalstudies,hashelpedprovideapictureofhowreconnectionoperatesinthecollisionlessenvironmentofthemagnetosphere.Still,however,wedonotfullyunderstandhowkeymicroscaleprocessesandlarge-scaledynamicsworktogethertodeterminethelocationandrateofreconnection.Whileinthelasttwentyyears,ithasbecomeclearthatinterchangeprocessesareimportantfortransportingplasmathroughtheplasmasheetintheformofburstybulkflowsandsubstormexpansions,westillhavenotreachedthepointwheresimulationsareabletorealisticallyanddefensiblyrepresentalloftheimportantaspectsofthephenomenon.Morethantwodecadesagoitwassuggestedthattheballooninginstability,thebasictheoryforwhichdatesfromthe1950s,mayplayanimportantroleinsubstorms.Nowthemajorityofexpertsagreethatregionsoftheplasmasheetareoftenlinearlyunstabletoideal-MHDballooning.However,itisalsoclearthatkineticeffectsintroduceimportantmodificationstotheMHDstabilitycriterion.Itisstilluncertainwhetherballooningplaysaleadingroleinsubstormsorhasjustaminorpart.Amongthedifferenttypesofsimulationsthathavebeenappliedtothesubstormproblem,globalMHDcodesareuniqueinthat,inasense,theyrepresenttheentireglobalsubstormphenomenon,includingcouplingtothesolarwindandionosphere,andtheimportantmechanismsofreconnection,interchange,andballooning.However,theyhavenotyetprogressedtothepointwheretheycanaccuratelyrepresentthewholephenomenon,becausegrid-resolutionproblemslimittheaccuracywithwhichtheycansolvetheequationsofidealMHDandthecouplingtotheionosphere,andtheycannotaccuratelyrepresentsmall-scaleprocessesthatviolateidealMHD.
%K Substorm
%K Reconnection
%K Interchange
%K Simulations
%U http://www.cjss.ac.cn/CN/abstract/abstract1537.shtml