pegwan
New member
I am attempting to run an idealised tropical cyclone simulation for the southern hemisphere, however I am running into some trouble when initialising the vortex.
In order to change the starting conditions, I am modifying 'module_initialize_tropical_cyclone.F' (user settings shown below).
Flipping the sign of the Coriolis parameter results in the intended Coriolis force for the southern hemisphere, however the actual winds of the initial vortex remain spinning counter-clockwise:
!-----------------------------------------------------------------------
! USER SETTINGS
! Parameters for analytic vortex:
! Reference: Rotunno and Emanuel, 1987, JAS, p. 549
r0 = 600000.0 ! outer radius (m)
rmax = 135000.0 ! approximate radius of max winds (m)
vmax = 15.0 ! approximate value of max wind speed (m/s)
zdd = 20000.0 ! depth of vortex (m)
! other settings:
fcor = -5.0e-5 ! Coriolis parameter (1/s)
sst = 30.0 ! sea-surface temperature (Celsius)
!-----------------------------------------------------------------------
For context, below is an ncview visualisation of horizontal-axis winds using the above settings:

Unfortunately, flipping the sign of vmax seemingly has no effect, with the vortex appearing identical to the image above.
Flipping the signs of r0 and rmax results in the complete absence of a vortex.
What actions can I take to create the desired simulation? Is there something here I have missed?
In order to change the starting conditions, I am modifying 'module_initialize_tropical_cyclone.F' (user settings shown below).
Flipping the sign of the Coriolis parameter results in the intended Coriolis force for the southern hemisphere, however the actual winds of the initial vortex remain spinning counter-clockwise:
!-----------------------------------------------------------------------
! USER SETTINGS
! Parameters for analytic vortex:
! Reference: Rotunno and Emanuel, 1987, JAS, p. 549
r0 = 600000.0 ! outer radius (m)
rmax = 135000.0 ! approximate radius of max winds (m)
vmax = 15.0 ! approximate value of max wind speed (m/s)
zdd = 20000.0 ! depth of vortex (m)
! other settings:
fcor = -5.0e-5 ! Coriolis parameter (1/s)
sst = 30.0 ! sea-surface temperature (Celsius)
!-----------------------------------------------------------------------
For context, below is an ncview visualisation of horizontal-axis winds using the above settings:

Unfortunately, flipping the sign of vmax seemingly has no effect, with the vortex appearing identical to the image above.
Flipping the signs of r0 and rmax results in the complete absence of a vortex.
What actions can I take to create the desired simulation? Is there something here I have missed?
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