Conventional observation,meteorological satellite,and NCEP analysis data are employed to study the interaction patterns between cold air and TC circulation and the effect of cold air on TC precipitation in two TC cases:Matmo and Soudelor.It is shown that there were obvious differences in precipitation distribution features induced by cold air in these two TCs:Matmo showing more meridional pattern;while Soudelor appearing a zonally shape.The trajectories of cold air parcels illustrated that the cold air interacted with Matmo through a northwest path including cold air from both northwest clod trough and Northeast China clod trough.Contradistinctively,the intrusion route of the cold air in Soudelor was from east,and the cold air source was only the cold trough system in Northeast China,so its intensity was much weaker.In vertical direction,the cold air intrusion at low levels was prior to that at middle levels in Matmo,and vice versa for Soudelor.These two TCs were affected by the different interaction forms of cold air.There was a distinct inverted trough at low levels with very strong cold-and warmtemperature advection and distinct surface frontogenesis in Matmo,and both the positive-vorticity and upward motion were located along the TC inverted trough with a northeast southwest distribution.As for Soudelor,with much weaker low-level cold-advection and surface frontogenesis,significant positive vorticity and upward motion were triggered by the low-level east wind jet in the north of TC circulation.Furthermore,the intensification of potential instability in the north of Soudelor caused by the middle level cold air intrusion finally resulted in the east-west distribution of heavy rainfall along the easterly jet to the north of TC.
NETL
NSTL
维普
万方数据
