During the severe precipitation, intruding of weak cold air in the mid-and upper-level makes convection strengthened and precipitation reinforced.
强降水期间，中高层弱冷空气侵入使对流加强和降水强度加大。
2
The polar ionosphere is strongly influenced by convection electric fields, auroral particle precipitation, and field-aligned electric currents etc.
极区电离层强烈地受到极区对流电场、极光粒子沉降和场向电流等的影响。
3
Supposing that the level of free convection is equal to the cloud bottom level, we considered the pulling effects of simulated sub-grid scale precipitation, which is under clouds.