On the Processes Leading to the Rapid Intensification of Typhoon Megi (2010)

Abstract

The processes leading to the rapid intensification (RI) of Typhoon Megi (2010) are explored with a convection-permitting full-physics model and a sensitivity experiment using a different microphysical scheme. It is found that the temporary active convection, gradually strengthened primary circulation, and a warm core developing at midlevels tend to serve as precursors to RI. The potential vorticity (PV) budget and Sawyer–Eliassen model are utilized to examine the causes and effects of those precursors. Results show that the secondary circulation, triggered by the latent heat associated with active convection, acts to strengthen the mid- to upper-level primary circulation by transporting the larger momentum toward the upper layers. The increased inertial stability at mid- to upper levels not only increases the heating efficiency but also prevents the warm-core structure from being disrupted by the ventilation effect. The warming above 5 km effectively lowers the surface pressure.

Document Details

Document Type
Pub Defense Publication
Publication Date
Apr 01, 2017
Source ID
10.1175/jas-d-16-0075.1

Entities

People

  • Chuan-chieh Chang
  • Chun-Chieh Wu

Organizations

  • Microsoft
  • National Science and Technology Council
  • Office of Naval Research Global

Tags

Readers

  • Atmospheric Science/Meteorology