[IDV #HVX-641068]: 20130530: need simple example of back trajectories in IDV

> 
> Hi Guys,
> 
> Can you give me a quick ABC on how to do back trajectories in the
> IDV?
> 
> One group of students here at the PASI will be working on transport
> of Saharan dust to the Caribbean, and it would be very useful to
> be able to illustrate the likely origins of air parcels sampled.
> 
> This will be used Friday afternoon in a computer lab.
> 
> Thanks in advance...
> 
> Cheers,
> 
> Tom

Tom,
    It is very easy to do.
1)Open a globe view window.

2)Load a dataset, gfs 1 degree, you may need more than one dataset since it 
takes pretty long time to move dust from Saharan to Caribbean, if so, aggregate 
them.

3)In the field Selector,  select momentum > derived > Grid 3D trajectory, click 
create display, when a window popup, select the colored by parameter. Note: it 
would be good to use property window to subset the time, use every other, or 
something, otherwise, it is too big to load every time step.

4)In the trajectory control, select level to 85000, inital area as "Rectangle", 
 and check the "Backward trajectory" box,  and draw a rectangle in the globe 
view window around the Caribbean region, and click "Create Trajectory"

The only thing I worry about is the internet speed if you are getting data from 
remote server.


Yuan

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> * Tom Yoksas                                            UCAR Unidata Program *
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Ticket Details
===================
Ticket ID: HVX-641068
Department: Support IDV
Priority: Normal
Status: Closed