Hi all,
I want to get a stable velocity field of the South China Sea, and I tried the below scheme: I used the SODA data (u,v,t,s,sla) as initial field; the boundary is set to time-invariable for 0:1:29(days); the forcing is also set to time-invariable (0:1:29).
with the above scheme, I wanted to get a stable velocity field for about 30 days. However, the velocity seems to increase monotonously and become much larger than the initial value.
Could anyone give me suggestions?
Thanks
best,
Yan
velocity increasing problem
velocity increasing problem
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Re: velocity increasing problem
You show before and after. What you need is a timeseries of total energy to see if you are approaching a steady-state. I'm not surprised that your ROMS grid supports sharper fronts than what came from SODA. What I don't know is the spin-up time for getting to steady-state. Or perhaps it will go unstable and get to an unsteady equilibrium.
Re: velocity increasing problem
Hi kate,kate wrote:You show before and after. What you need is a timeseries of total energy to see if you are approaching a steady-state. I'm not surprised that your ROMS grid supports sharper fronts than what came from SODA. What I don't know is the spin-up time for getting to steady-state. Or perhaps it will go unstable and get to an unsteady equilibrium.
Thanks for your kind reply. I have got the velocity field for the ninth month. I think it has gone unstable and unsteady with excessive eddies. any suggestions to reduce the excessive eddies？
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Re: velocity increasing problem
The eddying nature of your solution is to be expected at your resolution. If you go to 1 degree or coarser, the eddies should go away. Or you can crank up the viscosity to the point where it will damp out those eddies.