The trajectory matrix option will run a grid of
trajectories bounded by the first 2 source locations (trajectory
1 is the lower left grid point and trajectory 2 is the upper
right grid point) and evenly spaced with a grid increment given
by the distance between the lower left grid point (trajectory 2)
and trajectory 3. Only one height is allowed.
The trajectory ensemble option will start multiple trajectories
from the first selected starting location. Each member of the trajectory
ensemble is calculated by offsetting the meteorological data by a fixed
grid factor (one grid meteorological grid point in the horizontal and
0.01 sigma units in the vertical). This results in 27 members for
all-possible offsets in X,Y, and Z. Note: the starting height should
be greater than 250 m for optimal configuration of the ensemble.
The trajectory fequency option will start a trajectory from a single
location and height every 6 hours and then sum the frequency that the
trajectory passed over a grid cell and then normalize by either the
total number of trajectories or endpoints. A trajectory may intersect
a grid cell once or multiple times (with residence time options 1, 2 or 3).