Large-scale environmental influences on tropical cyclone formation processes and development time

Moreover, there is a stronger inward short-term (less than 10 days) angular momentumflux (AMF) at middle levels (800-500 hPa) before TCC formation. Conversely, in monsoon environments, TCCs have more MCSs, which are located farther from the TCC center. A stronger inward short-term AMF at low levels (1000-850 hPa) is observed before TCC formation and develops upward during the development of TCC to TC.

The characteristics of MCS and AMF are significantly correlated with the development time of TCC to TC. In summary, large-scale easterly and monsoon environments cause TCCs to have different MCS and AMF characteristics, leading to higher efficiency for TCCs developing into TCs in easterly environments compared to monsoon environments.