1. Western North Pacific Tropical Cyclone Formation and Structure Change
Project Title and Principal Investigator(s)
Background
Scientific Objectives
Field Experiment Requirements
Tropical Cyclone Structure-2008 (TCS-08) ONR/NRL Funded Projects
Monsoon depressions are the source of the large TCs in the western North Pacific (e.g., Harr et al Mon. Wea. Rev.).
Mesoscale convective systems within the monsoon depression determine the location and timing of TC formation
One of the primary mechanisms for changing the outer wind structure of a mature TC is the formation of a secondary eyewall (R. Stenger, PhD dissertation, in progress)
Western North Pacific Tropical Cyclone Formation and Structure Change
Patrick A. Harr
Russell L. Elsberry
Naval Postgraduate School
Monterey, CA 93943
Collect observations of the Mesoscale Convective Vortices structure and evolution in regions of tropical cyclone (TC) formation
Assess and advance the prediction of TC formation with COAMPS
Observe the external and internal processes leading to TC outer wind structure changes relative to the structure that exists at the time of formation
Observe and compare with COAMPS-predicted latent heating profiles during TC formation.
Sample the monsoon depression dynamic and thermodynamic structure leading up to formation time.
Obtain three-dimensional observations by the NRL P-3 ELDORA and Doppler wind lidar of the Mesoscale Convective System that forms near the center of a monsoon depression as merger with the depression circulation occurs
Monitor TC structure to document only small changes until secondary eyewall occurs, and then have NRL P-3 observations to document the role of an inward-spiraling outer rainband to complete the secondary eyewall