Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)

First Advisor

Lin, Yuh-Lang


With Geophysical Fluid Dynamic Model and Weather Research and Forecasting model, two tropical weather systems, African easterly wave (AEW) and Typhoon Morakot (2009), are studied, respectively. With regards to AEW, wave-like disturbances were generated on the lee side by vortex shedding for an easterly flow over an idealized mountain, with a wavelength of about 2000 km, a period of ~2-3 days, and a propagating speed of ~9.6 ms-1 which mimic an AEW. Thus an AEW may be generated by vortex shedding. Furthermore, these orographically generated hydrostatic, continuously stratified inertia-gravity waves on a β-plane are characterized as mixed Rossby-gravity waves based on the dispersion relationship.