Example 5 Trajectory Matrix

1
Example 5Trajectory Matrix

• Configure a regular matrix of source locations by
  defining three points, representing the lower
  left, upper right, and source spacing.

2
Run a trajectory matrix with NAMF40 forecast data
from the Workshop archive.
Enter the lower-left point 42N, 72W
Enter the upper-right point 50N, 64W
Enter the first source location to the NE of the
lower left point to define a 2 degree increment
44N, 70W This will define 25 starting locations
in the CONTROL file (5x5 matrix).
Click Next
3
Allow transfer to/from the GFS.
Vertical motion method Isobaric
Total run time 24 hours
Starting height 2500 m AGL
Vertical plot height units Pressure
4
Submit the job and view the results
5
Trajectory Endpoints File
The resulting graphic shows the matrix of 24-h
duration isobaric trajectories. Again there is
very little difference noted between the
trajectories indicating small temporal and
spatial differences in the meteorology in this
region. Note that we are using spatial and
temporal offsets to get at trajectory error or in
this case sensitivity to the meteorological data.
At the top of the trajectory endpoints file is a
list of the 25 starting locations created between
the selected lower-left and upper-right points.