The Distribution and Evolution of Multi-scale Moist energy within the Typhoon "Meranti"

The release of condensation latent heat associated with water phase changes is the most important non-adiabatic energy source in tropical cyclones (TCs) besides sea surface temperature, and will affect the energy conversion process inside TCs. Based on the derived moist atmospheric energy tendency equation in cylindrical coordinates,  the numerical simulation results were used in this paper to analyze the distribution and evolution characteristics of the multi-scale energy of Typhoon "Meranti".

The results showed that the high-value center of symmetric kinetic energy was always located at the Radius of maximum wind(RMW), distributed in a columnar shape and centrifugally inclined, whereas the high-value areas of asymmetric kinetic energy at the vortex scale and sub-vortex scale were mainly located in the strong updraft area within the eyewall and the low-level inflow area. At the strongest stage of the typhoon "Meranti", there also existed large kinetic energy in the middle-level inflow layer and the high-level outflow layer away from the vortex center. The high values of symmetric moist available potential energy were mainly distributed in the warm core and wet core within the eyewall, and their vertical stretching increased with the enhancement of the warm core structure and low-level moisture transport.

The moist available potential energy of symmetric vortices and asymmetric perturbations at each scale was generated by the non-adiabatic heating process at the corresponding scale, and was further converted into kinetic energy at the corresponding scale through vertical heat transfer.The research in this paper will help to analyze how the multi- water phase affect the energy and intensity of tropical cyclones from the energy perspective.