NUMERICAL EXPERIMENTS

Atmospheric and Ocean Waves-572

Experiment 4. Horizontal Jet over a circular topography.

We will analyze the solution of a jet U(y)=U*sin(PI*sin(y**2)**5 (this profil is like a Gaussian) that flows over a small isolated topography, for two cases A) No earth rotation and B) earth rotation.

A) NO EARTH ROTATION.

You need to modify your basic state, from the previous case U=Cte. U=U(y).

cp /t90/io/CLASS01/bastat.F .

Then modify your zeta_setup as follow: (this is assuming that you already modified zeta_setup for Experiment 3.

 jetset   = T      ; set a jet structure for the basic flow 
 jetbeg   = 35.    ; latitude of jet beginning [deg]
 jetend   = 55.	  ; latitude of jet end [deg]
The file spherical.h controls what horizontal coordinates the model uses; cartesian (FPLANE), spherical (SPHERICAL, this is the default) etc.

Comment in that file the #define SPHERICAL and uncomment #define FPLANE.

Remeber that:

Note that 3000 time spet will take close to 1800 sec. This is to much for an interactive job, run only for 2000 time steps. for longer runs, no more than 3600sec use gsub "script name"

* compare the solution with the barrier experiment for the same U velocity.

* Describe the structure of each of the dynamic variables in the steady state solution.

A) EARTH ROTATION on a FPLANE.

Using the same parameters than the jet experiment without rotation, You will run a case that includes the earth rotation

Open the file zeta_defines.h at the end of the list, the command #define NOROTATE

should be commented

c#define NOROTATE.

Note that 3000 time spet will take close to 1800 sec. This is to much for an interactive job, run only for 2000 time steps.

* compare the solution with the NOROTATION case for the same U velocity.

* Describe the structure of each of the dynamic variables in the steady state solution.

To see instructions on the model or commands for ferret and grads go back to 1st class.

for questions: I.Orlanski Isidoro.Orlanski@noaa.gov