...
FLEXTRA is an atmospheric trajectory model used by a large user community. It can be driven by meteorological input data from a variety of global and regional models including ECMWF analyses and forecasts.
FLEXTRA can compute both forward and background trajectories using various trajectory types such as: three-dimensional, model level, mixing layer, isobaric and isentropic trajectories. Trajectory computations can be carried out in the three different modes. These are as follows:
...
Rename it 'run_normal' and open up its editor.
First, set the input data parameters:
...
Here we set the run mode to 'NORMAL' and defined a set of forward trajectories starting on 11 January 2012 at 3, 9,12 and 15 UTC. We set the length of the trajectories to 72 h and specified that the output data (i.e. trajectory waypoints) will be written out every three hours.
| Warning | ||
|---|---|---|
| ||
FLEXTRA cannot start the computations from the very first available date and time. So we could start from 2012-01-11 00 UTC (the first available date and time in our data) as a starting date and time but had to use the next available step (3h). |
The last step is to define the starting point parameters:
...