Damages and deaths due to a tropical cyclone (TC) can easily occur at three places belong to a TC: the small ring area (SRA) of maximum sustaining wind around TC eye, the large ring area (LRA) of the rotating wind fie...Damages and deaths due to a tropical cyclone (TC) can easily occur at three places belong to a TC: the small ring area (SRA) of maximum sustaining wind around TC eye, the large ring area (LRA) of the rotating wind field around SRA and the skin air belt (SKAB) around LRA. However, weather forecasters only use the intensity of the SRA of a TC as the proxy to gauge the whole TC intensity, which led to many “non-major” TCs proved to be “deadly” TCs. This is called as “over-generalization problem” (OGP). Here we introduce a new way to measure the intensity of a TC. After investigating 156 deadly TCs in North Atlantic, we found an important feature: 83.3% of the top 156 deadliest TCs usually made landfalls along “five major tracks”. Furthermore, we found that the new intensity of those “deadliest” TCs kept almost unchanged with the increasing of time intervals at earlier stage from the genesis points, whereas the new intensity of those “safe” TCs increased in a line with much steeper slope. Using these two features, weather forecasters can have two more options to identify those “non-major” and “deadly” TCs by SSHS in future.展开更多
A new two-parameter count distribution is derived starting with probabilistic arguments around the gamma function and the digamma function. This model is a generalization of the Poisson model with a noteworthy assortm...A new two-parameter count distribution is derived starting with probabilistic arguments around the gamma function and the digamma function. This model is a generalization of the Poisson model with a noteworthy assortment of qualities. For example, the mean is the main model parameter;any possible non-trivial variance or zero probability can be attained by changing the other model parameter;and all distributions are visually natural-shaped. Thus, exact modeling to any degree of over/under-dispersion or zero-inflation/deflation is possible.展开更多
文摘Damages and deaths due to a tropical cyclone (TC) can easily occur at three places belong to a TC: the small ring area (SRA) of maximum sustaining wind around TC eye, the large ring area (LRA) of the rotating wind field around SRA and the skin air belt (SKAB) around LRA. However, weather forecasters only use the intensity of the SRA of a TC as the proxy to gauge the whole TC intensity, which led to many “non-major” TCs proved to be “deadly” TCs. This is called as “over-generalization problem” (OGP). Here we introduce a new way to measure the intensity of a TC. After investigating 156 deadly TCs in North Atlantic, we found an important feature: 83.3% of the top 156 deadliest TCs usually made landfalls along “five major tracks”. Furthermore, we found that the new intensity of those “deadliest” TCs kept almost unchanged with the increasing of time intervals at earlier stage from the genesis points, whereas the new intensity of those “safe” TCs increased in a line with much steeper slope. Using these two features, weather forecasters can have two more options to identify those “non-major” and “deadly” TCs by SSHS in future.
文摘A new two-parameter count distribution is derived starting with probabilistic arguments around the gamma function and the digamma function. This model is a generalization of the Poisson model with a noteworthy assortment of qualities. For example, the mean is the main model parameter;any possible non-trivial variance or zero probability can be attained by changing the other model parameter;and all distributions are visually natural-shaped. Thus, exact modeling to any degree of over/under-dispersion or zero-inflation/deflation is possible.
