Geoscience Reference
In-Depth Information
(
a
)
(
b
)
Fig. 10. The non-dimensional symmetric tangential wind profiles at 12 h for
(a) wavenumber 2 and (b) wavenumber 3 initial disturbances. To obtain tangential wind
in ms
−
1
, multiply by 50. To obtain radial displacement in km, multiply by 1000.
wavenumber 2 disturbance (Fig. 9(b)). It is again the down-shear tilt of the
asymmetric perturbation and so induced asymmetry-to-symmetry energy
transfer in the outer region that generate the second peak in the symmetric
tangential wind profile (Fig. 8).
For the same-structure initial perturbation, is there a preferred radius
location for the double eyewall formation? Our sensitivity experiments
with the same wavenumber 2 or 3 initial perturbation but with different
radial locations show that indeed there exists such an optimal radius.
When the perturbation is placed more outward (i.e. T25, T30, H25, and
H30) compared to the T20 and H20 experiments, the second peak in
the symmetric tangential wind profile becomes weaker (Fig. 10), which
means that the symmetric flows gain less energy from the asymmetric
perturbations. On the other hand, when the initial asymmetry is placed
more inward in T15 and T10 (H15 and H10), there is no obvious second-
peak in the tangential wind profile. Thus, the sensitivity experiments above
point out an optimal location near
2(i.e.twiceofRMW),wherethe
initial asymmetry may generate the most significant double peaks in the
symmetric tangential wind profile (Fig. 10).
r
=0
.
4. Summary
The role of two-way interactions between a symmetric core vortex and an
asymmetric disturbance in generating TC concentric eyewalls is examined
