Affiliation:
1. Key Laboratory of Geoscience Big Data and Deep Resource of Zhejiang Province School of Earth Sciences Zhejiang University Hangzhou China
2. Key Laboratory of Meteorological Disaster Ministry of Education / Joint International Research Laboratory of Climate and Environment Change / Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing China
Abstract
AbstractThis study investigated the kinetic and potential energy budgets during the slow (SI) and rapid intensification (RI) periods of Typhoon Mujigae, which occurred in October 2015, by conducting a Weather Research and Forecasting model simulation. We found that the kinetic energy conversion between asymmetric and symmetric rotational circulations in the lower troposphere plays a pivotal role in initiating the difference in the tendency of symmetric rotational kinetic energy between the RI and SI via the horizontal advection process of asymmetric circulations. Southerly and easterly environmental flows transported asymmetric anticyclonic flows in SI and cyclonic flows in RI to the radius of maximum wind, respectively, where asymmetric rotational circulation was developed by vertical shear of environmental flow. Such transports initiate the growth of symmetric cyclonic rotational circulation from SI to RI. The kinetic energy conversion of symmetric divergent circulations supported by symmetric potential energy accelerates the growth of symmetric rotational kinetic energy from SI to RI. These findings can shed light on the fundamental dynamics of the RI of tropical cyclones.
Publisher
American Geophysical Union (AGU)