Abstract Emanuel’s concept of maximum potential intensity (E-PI) estimates the velocity tropical cyclones from environmental parameters assuming thermal wind (gradient-wind and hydrostatic balances) slantwise neutrality in free troposphere. E-PI’s key equation relates proportionally radial gradients saturated moist entropy angular momentum. Here E-PI derivation is reconsidered to show that impl...

Iterative Hard Thresholding (IHT) is a class of projected gradient descent methods for optimizing sparsity-constrained minimization models, with the best known efficiency and scalability in practice. As far as we know, the existing IHT-style methods are designed for sparse minimization in primal form. It remains open to explore duality theory and algorithms in such a non-convex and NP-hard prob...

A numerical simulation of Typhoon Faxai (1915), which made landfall with a central pressure 960 hPa in the Kanto region Japan, was conducted using nonhydrostatic model 1-km grid spacing. sustained symmetric structure until and caused severe damage due to strong winds. The successfully simulated realistic track intensity for 48 h around landfall. time landfall, spatial size vortex small. Faxai, ...

Clouds within the inner regions of tropical cyclones are unlike those anywhere else in the atmosphere. Convective clouds contributing to cyclogenesis have rotational and deep intense updrafts but tend to have relatively weak downdrafts. Within the eyes of mature tropical cyclones, stratus clouds top a boundary layer capped by subsidence. An outward-sloping eyewall cloud is controlled by adjustm...

The fuzzy integrals are a kind of fuzzy measures acting on fuzzy sets. They can be viewed as an average membershipvalue of fuzzy sets. The value of the fuzzy integral in a decision making environment where uncertainty is presenthas been well established. Most of the integral inequalities studied in the fuzzy integration context normally considerconditions such as monotonicity or comonotonicity....

We review the four main paradigms of tropical cyclone intensification that have emerged over the past five decades, discussing the relationship between them and highlighting their strengths and weaknesses. A major focus is on a new paradigm articulated in a series of recent papers using observations and highresolution, three-dimensional, numerical model simulations. Unlike the three previous pa...

A decade has passed since the Hong Kong Observatory (HKO) and Government Flying Service (GFS) jointly commenced operational tropical cyclone (TC) reconnaissance over South China Sea in 2011, currently only such programme region a first USA terminated aircraft western North Pacific 1987. This paper reviews HKO–GFS flights between 2011 2020, including 24 storm-penetrating down to 2000ft 28 dropso...