National Oceanic and
Atmospheric Administration
United States Department of Commerce

Configuring LAS to regrid hybrid-z data to a fixed-z grid

Last modified: Mon, 04/11/2011 - 12:52
The output product can be on the native hybrid z grid, or regridded to a fixed z axis.

With Ferret as the backend, we can visualize or list data in itsnative form, or to regrid it to a fixed-z axis. In the xml for the dataset, we need to add two things:

  1. A Ferret property pointing to the thickness variable <thk_var>, and if it's in a separate dataset, the dataset containing that variable, <thk_url>
  2. A UI element so that the constraint is available to regrid curvilinear to rectilinear data. An example UI file is in Example_hybrid_Z_ui.xml
 <properties>
 <ferret>
 <thk_url>http://someplace.edu/thredds/dodsC/lthk</thk_url>
 <thk_var>lthk</thk_var>
 </ferret>
 <ui>
 <default>file:ui.xml#Example_hybrid_Z</default>
 </ui>
 </properties>

The file Example_hybrid_Z_ui.xml contains the constraint menu and the choice to view z slices in native Z coordinates (if NO is chosen, then the data is regridded to the axis shown by the interface).

 <menus>
 <menu type="constraint" name="Hybrid_ZText">
 <item values="Native_Z_section">Z slices in Native Z Coordinates</item>
 </menu>
 <menu type="constraint" name="Hybrid_ZOps">
 <item values="=">=</item> 
 </menu>
 <menu type="constraint" name="Hybrid_ZVal">
 <item values="yes">yes</item>
 <item values="no">no</item>
 </menu> 
 </menus>