2.7.3.7. Reading UHDAS (CODAS) ADCP NetCDF (*.nc) files into ODV

1) First, get Ocean Data View from http://odv.awi.de/.  These
instructions apply to Mac ODV version 4.3.9, but should hold for more
recent versions too, at least on the Mac.

2) Open os75nb.nc or 0s150nb.nc file as follows:
    - Click on file
    - Go to “Open with” in the “File” menu, and select “Other”
    - In menu “Choose Application”, enable “All Application” and go to
      ODV, bin_macx, odv4.app, then open odv4.app
    - Should get “Define netCDF Emulation” screen
    - Select (highlight) both Dimensions shown (Time and depth_cell)
    - When you do that, a bunch of corresponding variables should appear
      to the right
    - Click “Next”
    - Should get “Associate Meta Variables” screen; likely you will do
      nothing but select “Next”
    - Should get “Select Primary Dimension” screen: select “depth_cell” by
      clicking on it
    - Click “Next”
    - Should get “Subset Dimensions” screen

All your stations should show up here, along with a Map showing their
geographical location.  Unless you want to subset the data, just click
“Finish”

NOW WAIT: depending upon the number of stations, it may take a minute
or two to load the data into ODV (which you should see on the screen).

3) Once the data is in ODV:
    - View, Layout Template, Full Screen Map
    - Right-click, with cursor on the map, and select “Zoom” (note that if you
      can’t right-click, option-click should work as well).

There will be a red box around the map: you can pull in the edges to
select the area on the map where your data is – do so, hitting the
return key at the end to finish the operation.  If you mess up, repeat
by right-clicking again on the map and either zoom in or zoom out.

Alternatively, you can select “Valid Domain” and the area encompassing
your data should fill the map.

4) SAVE YOUR WORK: At this stage, it is a good idea to save your
progress so far: go to save view and your default view for these data
will be saved (you could call it “Map view.xview”).

Another thing you can do at this point is Export the data into a text
file (Export, ODV Spreadsheet File).  This will give you a text file
that you can manipulate separately, should you desire to do so.  Note
that ODV occasionally crashes, so saving your data is a good idea...

5) To view a specific Transect of the data (the whole point of the exercise!):
    - “View”, “Templates”, “1 Section Window”
    - Then, right-click on map and select “manage section”, “define section”
    - Then click once on each end of the desired transect, and hit return key
    - You should get a “Section Properties” menu
    - Name the section
    - Select the section coordinate (distance, longitude or latitude)
    - Select whether you want bathymetry or not

Look at the section on the map: if the red box around it doesn’t
encompass all your stations, then make the mean width of the section
wider so that it does.  Then hit OK.

Your section should show up with data.  It is a good idea to save the
section now, in case ODV crashes:

  - Right-Click on the map, Manage Section Save Section As: give it a name.
    Then if the program crashes, you can just load the section in this
    same menu.

Now you need to select your X, Y, and Z axes for the section.

There are a few ways to do this: the fastest way is to right-click on
the data plot, and select “Properties”

    -In Properties Window 1, General:
        - Select the BlueRed Palette (default selection is ODV palette)
    - On same menu, decide if you want a grid on your plot or not and
      select accordingly
    -Next go to the Data window in Properties Window 1:
        - X-axis: select Distance component (Latitude, Longitude,
         whatever you want)
        - Y-axis: select Depth (meters), click reverse range box too
        - Z-axis Meridional Velocity Compenent (or Zonal or whatever
         you want that is listed)
    - Next go to the Display Style window in Properties Window 1:
        - The best display will be to use a Gridded Field, so select that
          box (default is always original data)
        - Since ADCP data are usually quite dense, the X and Y scale length
         at the default of 20 is probably fine.  You can adjust this, but
         be careful not to obsure patterns in the data.
    - When done with these menus, hit OK

The data will probably still look a bit weird, as the scale for the
Z-parameter will probably default to something that is not ideal.  So,
right-click on the plot, and try selecting “Full Range” – if the plot
looks good, then see what the range is (should be something between
+1.5 and -1.5 or so) and select a range that will give you a
symmetrical distribution about zero (like +1.5 and -1.5 or narrower,
like +0.6 and -0.6, for example).  Right-click on plot again, and
select “Set Ranges” and put in the the range you decided on.

6) Page layout: If you want to have 2 plots on this page, one for
Zonal and one for Meridional velocities, for instance, then
right-click somewhere on the ODV page (NOT on the map or the plot),
and select “Window Layout”

The window will now show the current layout.  To change it,
right-click on the map or the section plot and move/resize or create a
new window as appropriate.  You can also change the X/Y/Z coordinates
here.  When you are done manipulating the window, hit the return key
and you will go back to the normal view for the windows.

7) To save a plot as a jpg/tiff/whatever, right-click on the plot,
select save as, then save as the format you want.  You can do this for
plots or maps.  If you like the layout of the entire page and want to
save it as a whole, you click somewhere on the white part of it, and
get the Save Canvas As menu.  It is a good idea to save the View again
(top, View, Save View As) when you get the individual plots and map to
look the way you want them to so you don’t have to re-create it every
time.

Note that when you exit ODV, if you have saved any views previously,
when you open ODV again, you can go to recent files and find them.

..