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RE: trouble mapping wind data in panoply

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MS
Michael Soracco, modified 4 Years ago.

trouble mapping wind data in panoply

Youngling Posts: 40 Join Date: 8/11/16 Recent Posts

I tried to map wind data in panoply and ran into some issues - I downloaded a netCDF file (Ocean Surface Winds - CCMP-Daily), and when I open it in panoply, the list of variables includes: latitude, longitude, nobs (number of observations), time, uwnd, and vwnd. I'm not sure how to get a plot using multiple variables - I think I need both the u-wind vector and the v-wind vector (this is a guess, I know nothing about wind data)? When I tried to plot each one individually, I get an error message: NcException: Could not init dimension variable time. Any tips? 

MS
Michael Soracco, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 40 Join Date: 8/11/16 Recent Posts
OK, two questions:
 
1. NcException: Could not init dimension variable time.
Not sure about this. I downloaded data from this dataset and it worked ok. https://oceanwatch.pifsc.noaa.gov/erddap/griddap/ccmp-daily-v2-0-NRT.html
Maybe a problem during the download? Try to download the data again and see if that fixes it. If not we can troubleshoot at office hours.
 
2. To plot combined u and v wind as vectors with Panoply (once we get the dataset working). 
You do need uwnd and vwnd. A nice set of instructions to plot the vectors are at this link: 
http://davidburchnavigation.blogspot.com/2020/01/viewing-netcdf-weather-files-in-panoply.html
 
Good luck.
-Dale
KM
Kaylyn McCoy, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 6 Join Date: 6/12/17 Recent Posts

I tried downloading the data again, but I got the same error message. Which variable did you map when it worked for you? 

MA
Melanie Abecassis, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 65 Join Date: 6/12/17 Recent Posts

Hi Kaylyn,

How are you trying to download the files?
​​​​​​​If using ERDDAP, can you copy the URL or send a screen shot?

KM
Kaylyn McCoy, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 6 Join Date: 6/12/17 Recent Posts

Here is the data request link: https://oceanwatch.pifsc.noaa.gov/erddap/griddap/ccmp-daily-v2-0-NRT.nc?uwnd[(2020-07-06T18:00:00Z):1:(2020-08-06T18:00:00Z)][(-78.375):1:(78.375)][(0.125):1:(359.875)],vwnd[(2020-07-06T18:00:00Z):1:(2020-08-06T18:00:00Z)][(-78.375):1:(78.375)][(0.125):1:(359.875)],nobs[(2020-07-06T18:00:00Z):1:(2020-08-06T18:00:00Z)][(-78.375):1:(78.375)][(0.125):1:(359.875)]

BC
Brett Cooper, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 9 Join Date: 4/13/20 Recent Posts

I also had some trouble getting wind data to work in Panoply. I tried downloading a dataset from the OSCAR 5 day average and one of the near real time. I couldn't get Panoply to open either, but for what it's worth, I was able to load it into R and do a little manipulation there on the 5 day average netCDF. I added a snip of the Panoply error I was getting after double clicking on "uwnd" (looks like it was the same as Kaylyn's), along with the nc files I got.

Attachments:

Attachment

DR
Dale Robinson, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 16 Join Date: 9/26/16 Recent Posts

Hi Brett,

There seems to be a glitch in the dataset's time attributes. Melanie is working to fix it.

error panoply
BC
Brett Cooper, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 9 Join Date: 4/13/20 Recent Posts

For what I need, I may switch my dataset to ASCAT. Using this dataset, it looks like I can get uwnd and vwnd by changing the "color" variable on the dropdown menu here: https://oceanwatch.pifsc.noaa.gov/erddap/griddap/ascat_daily_apdrc.graph?vwnd[(2020-03-27T00:00:00Z)][(-79.875):(80.125)][(-179.875):(179.875)]&.draw=surface&.vars=longitude%7Clatitude%7Cvwnd&.colorBar=%7C%7C%7C%7C%7C&.bgColor=0xffffffff

MA
Melanie Abecassis, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 65 Join Date: 6/12/17 Recent Posts

Hi Brett,
​​​​​​​Were you getting the same kind of error for OSCAR? We fixed CCMP, so it works in Panoply now, but OSCAR didn't have the same issue.

BC
Brett Cooper, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 9 Join Date: 4/13/20 Recent Posts

Sorry! I think I was getting my datasets mixed up. OSCAR is working great, thanks! CCMP is working for me now too. Thanks!

DR
Dale Robinson, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 16 Join Date: 9/26/16 Recent Posts

We think that the problem with the CCMP dataset is fixed. Try to download the data again and open in Panoply. 

error panoply
KM
Kaylyn McCoy, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 6 Join Date: 6/12/17 Recent Posts

It works! Thanks for the fix!

MA
Melanie Abecassis, modified 4 Years ago.

RE: trouble mapping wind data in panoply

Youngling Posts: 65 Join Date: 6/12/17 Recent Posts

yay!!