The SSEC Visualization Project

The Visualization Project at the Space Science and Engineering Center (SSEC) of the University of Wisconsin-Madison focuses on making advanced visualization techniques useful to Earth scientists in their daily work. We accomplish this goal by making two scientific visualization systems, named Vis5D and VisAD, freely available over the Internet, and by using these systems as testbeds for exploring and evaluating new techniques.

Vis5D

The Vis5D system is very widely used by scientists to visualize the output of their numerical simulations of the Earth's atmosphere and oceans. To see images generated by Vis5D, click on:

sulfer dioxide with iso-lines of nitric acid (the icons on the left of the image give scientists interactive control over the three-dimensional images as they are animated)
wind vorticity during the winter storm of March 1993
Florida thunderstorms generated by colliding sea breezes.

Vis5d is being used by the U.S. Environmental Protection Agency to visualize air quality models. Click here to read about our cooperation with the EPA.

We used Vis5D for experiments with the BLANCA Network as part of the Gigabit Testbed Project, and we adapted Vis5D to run in the virtual reality CAVE. We used Vis5D to generate The SIGGRAPH 94 Daily Weather Forecast demo in the VROOM (virtual reality room) at Siggraph '94.

We also used Vis5D to visualize a very large global coupled ocean-atmosphere climate model using a CAVE in San Diego connected via the high-speed I-WAY network to an SP-2 data server at Argonne National Labs, as part of the GII Testbed at the Supercomputing '95 Conference. Click here to see a Vis5D-CAVE view of sea surface temperatures and upper air winds from the global coupled ocean-atmosphere model.

Serving and Viewing Vis5D Files Via the Web

Scientists are using the World Wide Web to exchange the output of their models as Vis5D files. Links to Vis5D files are embedded in Web pages, just as links to GIF files are embedded in Web pages, and Web browsers invoke Vis5D to view them, just as browsers invoke xv to view GIF files.

Sites regularly serving model output as Vis5D files via the Web include:

The University of Wisconsin serving output from the Non-hydrostatic Modeling System.
The National Environmental Satellite Data and Information Service serving output from the CIMSS Regional Assimilation System.
The National Weather Service's Environmental Modeling Center serving output from the ETA model.

In order to view these model runs, you must install Vis5D and set up your Web browser (e.g., Netscape or Mosaic) to invoke Vis5D as an external viewer. Click here to find out how to do it, or to find out how to serve your own model runs via the Web.

VisAD

The VisAD system enables scientists to interactively steer and visualize their computations. The VisAD system is based on very general conceptual models of data, computation and display, in order to adapt easily to a wide variety of scientific applications. The ftp distribution of the VisAD system includes a large set of well-documented scientific algorithms and data sets that serve as a tutorial for understanding how the system's data, display and computational models can be applied. The VisAD system's lattice data model is described in our IEEE Visualization '94 paper (see reference below) and in a longer document available in this ftp archive.

Click here to see a screen shot of VisAD. It shows a time sequence of GOES satellite images displayed in four different ways. The upper-right window shows a single image with the infrared channel mapped to red and the visible channel mapped to blue-green. The upper-left window shows the infrared channel mapped to height in order to create a terrain (note the image is partitioned into 16 rectangular regions). The lower-right window shows the time sequence of four images stacked up along the vertical axis, and only pixels with infrared radiances in a selected range are displayed. The lower-left window shows one region of one image displayed as a colored three-dimensional scatter diagram - infrared and visible channels are mapped to the horizontal axes, a spatial variance of the infrared channel is mapped to the vertical axis, and an infrared texture is mapped to color. These images are used to diagnose problems with a cloud discrimination algorithm.

Mesa

You may also be interested in Mesa, which is available from our ftp server. Mesa is a 3-D graphics library with an API which is very similar to that of OpenGL.* To the extent that Mesa utilizes the OpenGL command syntax or state machine, it is being used with authorization from Silicon Graphics, Inc. However, the author makes no claim that Mesa is in any way a compatible replacement for OpenGL or associated with Silicon Graphics, Inc. Those who want a licensed implementaion of OpenGL should contact a licensed vendor. This software is distributed under the terms of the GNU Library General Public License, see the LICENSE file for details.

* OpenGL(R) is a registered trademark of Silicon Graphics, Inc.

Publications

Here are a few publications of the SSEC Visualization Project:

Interactive Visualization of Earth and Space Science Computations
W. L. Hibbard, B. E. Paul, D. A. Santek, C. R. Dyer, A. L. Battaiola, and M-F. Voidrot-Martinez, Computer 27, No. 7, July 1994, 65-72.
A Lattice Model for Data Display
W. L. Hibbard, C. R. Dyer, and B. E. Paul, Proc. IEEE Visualization '94, 1994, 310-317.
Display of Scientific Data Structures for Algorithm Visualization
W. Hibbard, C. R. Dyer, and B. Paul, Proc. IEEE Visualization '92, 1992, 139-146.
Interactive Atmospheric Data Access Via High Speed Networks
W. Hibbard, D. Santek, and G. Tripoli, Computer Networks and ISDN Systems 22, 1991, 103-109.
The VIS-5D System for Easy Interactive Visualization
W. Hibbard, and D. Santek, Proc. IEEE Visualization '90, 1990, 129-134.
Visualizing Large Data Sets in the Earth Sciences
W. Hibbard, and D. Santek, Computer 22, No. 8, August 1989, 53-57.
Interactivity is the Key
W. Hibbard, and D. Santek, Proc. Chapel Hill Workshop on Volume Visualization, 1989, 39-43.
Application of the 4-D McIDAS to a Model Diagnostic Study of the Presidents' Day Cyclone
W. Hibbard, L. Uccellini, D. Santek, and K. Brill, Bull. Amer. Met. Soc. 70, 1989, 1394-1403.
4-D Display of Meteorological Data
W. Hibbard, and D. Santek, Proc. 1986 Workshop on Interactive 3D Graphics, 1986, 23-36.
Computer Generated Imagery for 4-D Meteorological Data
W. Hibbard, Bull. Amer. Met. Soc. 67, 1986, 1362-1369.
3-D Weather Displays Using McIDAS
W. Hibbard, R. Krauss, and J. Young, Preprints, Conf. Interactive Information and Processing Systems for Meteorology, Oceanography, and Hydrology, 1985, 153-156.
An Efficient Method of Interpolating Observations to Uniformly Spaced Grids
W. Hibbard, and D. Wiley, Preprints, Conf. Interactive Information and Processing Systems for Meteorology, Oceanography, and Hydrology, 1985, 144-147.

Video Publications

And here are a few video publications of the SSEC Visualization Project:

Verifying a Weather Model Using Satellite Observations
W. Hibbard, and B. Paul, Siggraph Video Review 114, 1995.
Computational Steering with VisAD
W. Hibbard, and B. Paul, Siggraph Video Review 108, 1995.
Real-time Volume Rendering of Downbursts
W. Hibbard, and B. Paul, Siggraph Video Review 105, 1994.
Hurricane Gilbert
W. Hibbard, and B. Paul, Siggraph Video Review 105, 1994.
Energy Generation by Controlled Thunderstorm
W. Hibbard, and B. Paul, Siggraph Video Review 82, 1992.
Using VIS-AD to visualize a cloud discrimination algorithm
W. Hibbard, and B. Paul, Video Proceedings of IEEE Visualization '92, 1992.
El Nino Satellite Observations and Downburst Simulation
W. Hibbard, and D. Santek, Siggraph Video Review 74, 1991.
Cold Fronts Moving Across the North Atlantic
W. Hibbard, and D. Santek, Siggraph Video Review 61, 1990.
Volume Visualization of Clouds
W. Hibbard, Siggraph Video Review 44, 1989.
Interactive Earth Science Visualization
W. Hibbard, and D. Santek, Siggraph Video Review 43, 1989.
Visualization of Four-dimensional Meteorological Data
W. Hibbard, D. Santek, and G. Dengel, Siggraph Video Review 37, 1988.
Presidents' Day Storm
W. Hibbard, and D. Santek, Siggraph Video Review 35, 1988.

You can obtain copies of most of these videos from the Siggraph Video Review.

If you are in Europe

Recently users in Europe have had problems with low bandwidth to North American ftp servers. The Deutsches Klimarechenzentrum has offered to serve as a mirror site for our software. See the Vis5D homepage and the VisAD homepage for links to their ftp server.

Or, you can click here to browse their server.

More Information

Here's a comprehensive list of scientific visualization web sites.

For broader information try the New York Times on the Web, the Yahoo directory or one of these Web searchers.

For more information about the SSEC Visualization Project please contact Bill Hibbard or Brian Paul.