Inthecontextofadvectiondynamics,19experiments(Exps.)areperformedusingaquasi-geostrophicbarotropicvorticityequationmodeltoexploretheconditionforthemergenceofbinaryvorticesandtheself-organizationofthelargerscalevortex.Resultsshowthattheinitialdistancebetweenthecentersofbinaryvorticesandthenon-axisymmetricdistributionsoftheirinitialvorticityaretwofactorsaffectingthemergenceofbinaryvortices.Thereisacriticaldistanceforthemergenceofinitialsymmetricbinaryvortices,however,themergenceofinitialnon-axisymmetricbinaryvorticesisalsoaffectedbytheasymmetricstructureofinitialvortices.Theself-organizationprocessesin19experimentscanbeclassifiedintotwotypes:oneisthemergingofidentical,axisymmetricbinaryvorticesinwhichtheinteractionofthetwovorticesundergoesslowlychange,rapidchange,andtheformation,stretching,anddevelopmentofthefilamentsofvorticity,andthetwovorticesmergeintoasymmetricvortex,withitsvorticitypiledupintheinnerregioncomingfromthetwoinitialvortices,andthevorticityofthespiralbandintheouterregionfromthestretchingofthefilamentsofthetwoinitialvortices.Andtheothertypeisthemergingofthetwonon-axisymmetricinitialvorticesofanellipticvortexandaneccentricvortexinwhichtheellipticvortex,ontheonehand,mutuallyrotates,andontheotherhandmovestowardsthecenterofthecomputationaldomain,atthesametimeexpandsitsvorticityarea,andatlastformstheinnercoreofresultantstatevortex;andtheeccentricvortexmutuallyrotates,meanwhilecontinuouslystretches,andfinallyformsthespiralbandofresultantstatevortex.Theinteractionprocessischaracteristicofthevorticitypiledupintheinnercoreregionofresultantstatevortexoriginatingfromtheellipticvortexandthevorticityinspiralbandmainlyfromthesuccessivestretchandruptureoftheeccentricvortex.
