Exercise #5




  • Problem #1 - The computational error tutorial showed only minor differences when the initial trajectory height was 750 m. Repeat the calculation using an initial height of 10 m.

  • Hint - Retrieve traj_fwrd_control.txt to get started or edit and run traj_error.bat.

  • Solution - Can you explain why the trajectories diverge?

  • Problem #2 - See if you can figure out how to use the Run Daily menu to create a graphic with hourly mid-bounday layer trajectories for 24 h starting at 1700 UTC.

  • Hint - Retrieve traj_fwrd_control.txt and edit the trajectory setup menu to define a simple output file name with just one letter: T. Then open the Special Runs / Daily menu and set the start interval and duration to one followed by execute script to obtain 24 trajectories, one per output file.

  • Solution - Open the command line prompt and go to the HYSPLIT working directory and create a file of trajectory file names by entering the command dir /b T8309* >INFILE. Then open the trajectory plotting menu and enter +INFILE into the input endpoints field to obtain the multi-trajectory graphic.