IDV Status Report

Yuan Ho, Julien Chastang and Sean Arms
April, 2012

This report updates the status of Unidata's IDV development efforts since the last report (October, 2011).


In the Unidata 2013 proposal, IDV development was defined under the proposed thematic area 3, "Developing and deploying useful tools". The following goals were outlined in this area:
  1. Ability to access and visualize every data stream provided by Unidata.
  2. Support for analysis and visualization of ensemble model output (e.g., probabilistic threat and multivariate probabilities, mean-spread analysis, spaghetti diagrams, and aggregated remote access to large ensemble archives).
  3. Improved handling of sub-minute data (lightning and model) as well as long range climate data.
  4. Support for field project operations and datasets.
  5. Adaptation to GIS frameworks and integration of GIS data.
  6. Enhancements to the IDV framework and plug-in capabilities for a range of customized applications (e.g., lightweight IDV for use in educational settings).
The numbers are not in order of priority, but are used to indicate steps toward that goal in this report.

Progress since last report:

  • Two update versions 3.0u1 and 3.0u2 have been released since IDV 3.0 release. The latest update can be download at

    Some of the new features in this release include:

    • Added support for the new NEXRAD AR2V007 format and new radar stations. (Goal 1)
    • Added function to flip the grid along the central longitude, useful for converting 0-360 to -180 to 180 or vice-versa. (Goal 2)
    • Added funciton to calculate and display the grid trajectory, useful for visualization of the air parcel movement. (Goal 2)
    • Added fucntion to convert pressure to topography, defaulting to the standard atmosphere. (Goal 2)
    • All wind barb displays now use the same rendering scheme. The effect is that winds less than 2.5 knots, but greater than 0 will show as a staff with no flags. Previously, they were drawn as circles (calm). (Goal 3)
    • Added daily climatology functions clmDay and calcDayAnom. (Goal 2)
    • Added clockwise and counterclockwise rotation options so you can rotate about the north and south poles in globe view (or others). (Goal 6)
    • Augmented APIs to allow the ISL script to change probing location and time series chart name. (Goal 6)
    • A new version of netCDF-Java library (4.2.30) is included in this release. Among the changes are fix for Gaussian latitude grids in GRIB and a fix for NARR. (Goal 1)

    See the IDV 3.0U2 Release Notes for more information.

  • Unidata IDV team and its collaborators held a two days meeting in Madison, Wisconsin last November for the purpose of strengthening the collaboration between the IDV and the McIDAS-V projects. (Goal 6)
  • A two days IDV regional workshop was held in the California Univerisity at Pennsylvania on February 16 and 17. (Goal 6)
  • The IDV project hss officially moved to GitHub as a fully open source project. IDV-Github (Goal 6)
  • According to a recent survey of the WRF user group, there are about 17% of WRF users currently using the IDV or are interested in using the IDV. The number is identical to the GrADS package usage in the WRF community.
  • The IDV team gave a presentation of the IDV usage to WRF data assimilation group on December 20, 2011. This talk covers the area of the IDV display capabilities, integration of the observation and the WRF model output, and some basic analyzing features in the IDV.
  • The IDV team will conduct a two hours tutorial session in the WRF workshop in coming June, expecting 40 to 50 participants and focusing on the displaying and analyzing the WRF model output.
  • Meetings/Presentations:
    • Yuan, Julien and Sean attended the 2012 New Orleans AMS Meeting and presented IDV and RAMADDA demonstrations at the Unidata booth.
    • Yuan attended the 2011 AGU fall Meeting and gave a presentation in the visualization workshop.

New development:

Development is underway for the next release of the IDV (3.1) which should be released in a few months. Several of these features are already available for testing in the IDV nightly and test release. nightly build.
  • Time matching feature to allow users to use times of one display to control displays of other datasets.
  • Additional ensemble functions: multivariate ensemble probabilities.
  • Support for CF Radial NetCDF datasets. (Goal 1)
  • Support for GEMPAK surface and upper air data. (Goal 1)
  • Axis scale and labeling interface. (Goal 1)
  • Adde chooser satellite image preview feature. (Goal 1)

Ongoing efforts include:

  • Integrate the McIDAS-V's modification of the image chooser into the IDV.
  • Remote data access through NetCDF remote protocol. (Goal 1)
  • Improved geospatial handling to allow data selection based on existing displayed data. (Goal 3)
  • Continued labeling and color bar improvement work with SSEC.
  • Working with CDM/TDS groups on improving access and display of COSMIC data. (Goal 1)
  • Collaborating in the development of VisAD and McIDAS-V.
  • Keeping up with new Java interfaces and developments.
  • Continue to provide support to the IDV community.
  • Various IDV bug fixes and enhancements.


IDV usage:

  • IDV usage count
  • Top ten known sites are University of Wisconsin (Mc-V), China, Millersville University, University of Oklahoma, University of Twente, Mexico, NCAR/RAL, EUMETSAT, Plymouth State university and Lyndon State university.

    Metrics data: April 1 2011 to September 31 2011

    **When the IDV starts up interactively (i.e. not in script mode), it accesses some resource files (e.g. Favorite Bundles list) from the Unidata web server. The standard web server logs are used to generate information on what sites are running the IDV.

    This document is maintained by Yuan Ho <>