How Much Vertical Shear Can A Well-Developed Tropical Cyclone Resist?
Yuqing Wang, International Pacific Research Center, University of Hawaii, Honolulu, HI; and M. T. Montgomery and B. Wang Among many limiting factors, the unfavorable environmental conditions, especially the vertical shear-induced asymmetry in the inner core region, have been postulated as the primary impediment to a tropical cyclone reaching its maximum potential intensity (MPI). A related question is how strong vertical shear a mature tropical cyclone can resist. Observations from the western North Pacific and other regions show that in most circumstances strong tropical cyclones can resist vertical shear as strong as 15-20 m/s. Recent theoretical studies demonstrate that even dry tropical-cyclone-like vortex can survive against modest vertical shear. However, the numerical study by Frank and Ritchie (2001) showed that even in a 5m/s vertical shear a strong tropical cyclone could be substantially weakened in two days. They attributed the weakening of the storm to the outward transport
