• ClamsTools
• lyapunov

Program lyapunov

This program calculates the lyapunov exponent and adds it to the clams file.

Arround every point in the clams file (init file) a circle with a specified radius and a specified number of points is created. For all these points trajectories (max. 24 hours) are calculated by calling traj. Then the lyapunov exponent for all points in the clams file is calculated and added to this file.

Configuration file

The options for the execution of lyapunov can be set in the configuration file lyapunov.inp:

1)  12 09 08 2003                                ! date
2)  /private/icg112/clim/BN0_ECZ_3d_24_1.5       ! directory with init files
3)  BN0                                          ! prefix of init files
4)  /usr/nfs/clams/icg125/cawses/isen_zeta/links ! directory with wind files
5)  ECZ                                          ! prefix of wind files
6)  /private/icg112/lyap                         ! output directory
7)  24                                           ! time step (in hours)
8)  y                                            ! y/n -> backward/forward run 
9)  y                                            ! y/n -> 3d/2d run 
10) 100.                                         ! circle radius in km
11) 6                                            ! number of APs/circle
12) icg112                                       ! userid
13) N.Thomas                                     ! user name
14) /home/icg1/icg112/clams/traj/traj            ! traj executable

Remarks:

1. Date of init file
2. Directory with init file
3. Prefix of init file consisting of three characters

   The init file name corresponds to the format init_xxx_yymmddhh.nc with the prefix xxx in line 3 and the date specified in line 1.

4. Directory with wind files used by program traj

5. Prefix of wind files

   The filenames must correspond to the format isen_xxx_yymmddhh.nc. The prefix xxx must be specified in this line.

6. Output directory for temporal files (pos file used by traj and trajectory file created by traj)

7. Length of trajectories in hours (max. 24)

8. Specification, if forward or backward trajectories should be calculated:
   y = backward trajectories
   n = forward trajectories

9. 2d or 3d trajectory run:
   y = 3d run (with theta_dot)
   n = 2d run (without theta_dot)

10. Circle radius in km

11. Number of air parcels per circle
    Arround every point in the clams file a circle with the specified radius and the specified number of points is created.

12. Userid
13. User name
14. Traj executable