A Numerical Study of the Track Deflection of Supertyphoon Haitang (2005) Prior to Its Landfall in Taiwan. REFERENCE: Jian, G.-J., and C.-C. Wu, 2008 : A Numerical Study of the Track Deflection of Supertyphoon
Jian, G.-J., and C.-C. Wu, 2008: A Numerical Study of the Track Deflection of Supertyphoon
Haitang (2005) prior to its landfall in Taiwan. Mon. Wea. Rev., 136, 598-615.
Speaker: Chen, D-S
Advisor : Prof. Yang, M-J
The three question:
1)What dynamical processes are responsible for Haitang’s track deflection before landfall in Taiwan?
2)What is the role played by Taiwan’s terrain?
3)What is the impact of the vortex structure ,that is, with different values of structure parameter in the initial vortex?
TD 230 N
TS 17 m/s 00Z 12 July 2005
TS 33 m/s 18Z 13 July 2005
Guam NNE 900 Km
ST 51 m/s 06Z 16 July 2005
# Max. intensity
Wind speed 55 m/s 15Z 16 July
MSLP 912 h Pa
About 30 km north of Hua-Lien at 0650 UTC 18 July
Hua-Lien (METEOR 1000S)
18Z 17 July ~ 05Z 18 July
• The NCAR–AFWA bogusing scheme (Davis and Low-Nam 2001) to implant an initial Rankine vortex into the operational CWB NFS analysis.
The Rankine vortex is
dBz 17/18Z ~ 18/05Z
CTRL 27h ～ 42h
Max. Wind Speed (m/s)
28h 29h 30h 31h 32h 33h
W 45.8 47.9 50.7 52.2 53.9 55.3
E 51.3 54.1 55.2 51.7 50.3 50.4
W-E -5.5 -6.3 -4.50.5 2.6 4.9
Average asymmetric flow
Storm motion vector
N Haitang (2005) Prior to Its Landfall in Taiwan
Max. tangential wind inside the radius
The higher Vmax before about 31h is on the northeastern , between 31 and 35 h, the max. shifts to the western side of the storm.
The advection wind vectors ( red arrow) of H70 and H40 experiment are also pointing to the southwest.
The storm motion vector (yellow arrow) parallel with 700 hPa.
The region of stronger wind in H10 and FLAT simula-tions generally appears in the NNE.
Moving westward with translation speed of 1.5 m/s and 2.3 m/s, which agree well with the adv-ection wind vectors
A35 A47 CTRL Haitang (2005) Prior to Its Landfall in Taiwan
MMTW (m/s) 52.3 47.4 42.1
MSLP (hPa) 941 952 960
RMWs (km) 70 65 60
MMTW : max. mean tangential wind
MSLP : mean sea level pressure
RMW : the radius of max. windNumerical Results
~ THANK YOU ~ Haitang (2005) Prior to Its Landfall in Taiwan