Features of variation in total, barotropic and baroclinic kinetic energy with the mechanism explored around the 1998 scs summer monsoon onset

This paper concerns atmospheric kinetic energy variation related to the onset of summer monsoon in May, 1998 over the SCS (South China Sea).Results show that around the onset, noticeable conversion occurs in atmospheric total, barotropic and baroclinic kinetic energy (KE) at 300-1000 hPa;three days before the onset, total and barotropic KE are already growing markedly and baroclinic KE increases simultaneously with the onset:the monsoon's onset is associated closely to the meridional propagation of barotropic and baroclinic KE in the SCS region and study of equations of barotropie/baroclinic KE indicates that the net production term is the dominant factor for the change of the two forms of KE, the term of fluxes plays a part in weakening the energies and the conversion term is responsible for transforming barotropic into baroclinic KE.