CONSTRUCTION AND APPLICATION OF GENESIS POTENTIAL INDEX FOR TROPICAL CYCLONES
Tropical cyclogenesis is one of the mysteries in atmospheric science. This subject becomes more important in recent years due to the increasing concern over the tropical cyclone (TC) activity under the influence of climate change. Large amount of studies are focusing on the large-scale environmental parameters which are favorable for TC formation. Such conditions are typically fulfilled by the atmosphere over the tropical ocean during summer time, but they do not always lead to the formation of tropical cyclones. The poor understanding of the formation mechanism leads to poor prediction of genesis events. Empirical genesis potential index, which aims to predict the frequency of formation event based on the large-scale environmental conditions, was first proposed by Gray (1977) and this idea has been extended by many others (e.g. Emanuel and Nolan 2004). Genesis potential index has been extensively used for short-term forecasting and projection based on future climate. However, the ability of the existing indices in predicting the number of genesis event is poor. This seminar will discuss why those indices have a poor performance and how to make a better index.