The size characteristics and physical explanation for the radius of maximum wind of hurricanes

In the present study, we conducted four idealized hurricane large-eddy simulation cases to investigate the size characteristics of the different radius of maximum wind (RMW) of hurricanes at different intensity levels. The RMW shows different characteristics for different grid resolutions and hurricane intensities, which shows a similar trend to absolute angular momentum. Thus, the absolute angular momentum consideration was proposed to explain the radial distribution of RMW in different hurricane intensity cases. This physical mechanism is that diabatic heating induces the enhancement boundary layer inflow in spiral rainbands. Then the considerable absolute angular momentum would be brought into the hurricane eyewall region with the strong radial inflow induced by this diabatic heating, increasing the tangential wind outside the eyewall, and thus leading to an outward expansion of the tangential velocity wind field, and finally, the RMW size increases.

Automated summary

In this study, we conducted simulations of four hurricane cases to investigate the size characteristics of the radius of maximum wind (RMW) at different intensity levels. The results show that the distribution of RMW exhibits a similar trend to absolute angular momentum. By considering the physical mechanism of absolute angular momentum, we explained the radial distribution of RMW in different hurricane intensity cases.