DIVERGENT AND ROTATIONAL WIND KINETIC ENERGY BUDGET AND CONVERSION DURING A TORRENTIAL RAIN PROCESS CAUSED BY TYPHOON LOW PRESSURE TROUGH

Divergent and rotational wind kinetic energy budget and conversion during a torrential rain process caused by typhoon low pressure trough are calculated using the complete equations of budget of divergent and rotational wind kinetic energy.The results show that the increment of the kinetic energy in the torrential rain area is one of the main contributions to the amplification of the torrential rain,while the rotational wind kinetic energy generation GK is the principle energy source,the horizontal flux HF provide convergence,especially in the lower troposphere,the sub-grid scale kinetic energy generation term change from the energy sink into the energy source in the torrential rain process.The energy conversion term C(KD,KR) is always positive which show that energy transformed from KD to KR,with the maximum in the lower troposphere as the torrential rain enhancement,and the term AF has the most important role during the energy conversion.It is also denoted that there is the enhancement of the baroclinic instability and the decrement of the barotropic stability during the torrential rain process,and the enhancement of the baroclinic instability in the lower troposphere is an important reason for the am plification of the torrential rain.