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[IDV #WHS-790529]: Issue with bottom velocity vectors

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  • Subject: [IDV #WHS-790529]: Issue with bottom velocity vectors
  • Date: Wed, 01 Jul 2015 15:34:12 -0600
Rich,

Here are a few comments:

- Update your IDV to the latest version (5.1u2, this will yield no improvement
probably, but it is usually best to work with the latest version of the IDV).

- For clarification, the flow vectors are supposed to be derived from what? The
data contain two u and v fields (momentum versus stokes). Which one are you
interested in? (I wonder if there is confusion/mismatches going on here.)

- Are you sure you are looking at the same geographic extents? The IDV is
displayed roughly over NY harbor. I cannot tell where the Python plot is
located.

- I wonder if there are numerical errors going on. One of the Derived Fields in
the IDV is "Speed (from U & V)".  When you do a "Value Plot" of these data, do
you get numbers you expect?

- Experiment with the Flow Vector Control in the IDV Dashboard, Displays Tab.

Keep us up-to-date on your progress.

Best,

Unidata IDV Support




> IDV Gurus,
> 
> We are struggling to get bottom velocity vectors displayed properly in
> IDV (5.0u2) for a Hurricane Sandy ocean simulation.
> 
> The bottom velocity for 2012-10-30 00:00:00 should look like the 1st
> attached image (plotted in python using this notebook):
> http://nbviewer.ipython.org/gist/rsignell-usgs/a85e68a71933910a171a
> 
> but instead it looks like the 2nd attached image.
> 
> In the IDV image you can see that the flow at the coast is the wrong
> direction, and there are those strange black areas with no vectors.
> 
> What is going on here?
> 
> I'm attaching the bundle so you can recreate this yourself.
> --
> Dr. Richard P. Signell   (508) 457-2229
> USGS, 384 Woods Hole Rd.
> Woods Hole, MA 02543-1598
> 
> 


Ticket Details
===================
Ticket ID: WHS-790529
Department: Support IDV
Priority: Normal
Status: Closed