A Four-Member CCT Team Creates a Computer Visualization of Hurricane Katrina
Can a three-dimensional visualization of Hurricane Katrina better educate scientists about the nature of hurricanes? LSU’s Center for Computation and Technology (CCT) is betting on it. A four-person team from CCT has created a visualization based on data from different sources. The team hopes that this data will help:
- Scientists, to study and predict hurricanes
- Decision makers, to decide what is best for citizens of the Gulf Coast
- Citizens, to decide how to prepare for an approaching hurricane
The Visualization
The Hurricane Center has used the ADvanced CIRCulation model (ADCIRC) to forecast hurricane storm surges since 2002. ADCIRC is a surface simulation that is formulated on LSU’s supercomputer, Mike, to predict storm surges based on projected hurricane paths. After wind velocity, atmospheric temperature, and pressure are inputted, the ADCIRC simulation provides surge height and water flow direction data.
But if ADCIRC works so well, then why is the atmospheric visualization such a big deal?
“The ADCIRC simulation is a purely theoretical case demonstrating what happens when a hurricane directly hits New Orleans,” said CCT staff member Werner Benger. “In contrast, the atmospheric model stems from a simulation which was synchronized with observations. So the atmospheric model depicts the real path of Katrina, which was a little east of the city.”
CCT and the Hurricane Center discussed the concept of presenting hurricane data in a three-dimensional form in early 2005. However, they were overly committed to another project, said LSU staff member Shalini Venkataraman.
“The onslaught of Katrina certainly accelerated our efforts. Just after Katrina hit, [CCT] was invited by the Supercomputing ’05 steering committee to make a presentation on computational and visualization challenges for Katrina (and beyond),” Venkataraman said. “This was a good opportunity to make a case to the wider community about the challenges and opportunities of modeling our coast and to build up a national alliance of researchers. That’s what gave us the impetus for our visualization efforts.
“The objective was to have a comprehensive presentation, pulling together modeling and visualizations showing the development of the hurricane’s wind fields, the approach, the storm surges, wave models, [geographic] data, comparisons to what actually happened, and also post-Katrina studies of what went wrong.”
She added that they are hoping for “new approaches to do a much more sophisticated job of forecasting in the future.”
The project began with CCT gathering basic hurricane data to present at the Supercomputing ’05 conference in Seattle, Washington. The international conference is one in which organizations showcase innovations in high-performance computing, networking, storage, and analysis.
“The original plan [for the visualization] had been to just show data from the ADCIRC model, plus some photographs depicting the land,” said Benger. “However, it became clear quite soon that just looking at a surface is visually boring and that we could not learn much from just visualizing an existing, single dataset.”
To make the visualization more interesting and more educational, the team started to incorporate more data. “Most of the time [spent on this project] in autumn ’05 was just communication efforts to find out where to get which data and how to interpret them,” said Benger.
“Finally, we came up with an atmospheric dataset which encompasses the date Katrina hits New Orleans, and we could show a three-dimensional visualization at Supercomputing ’05.
Supercomputing ’05 took place in November. At this time, the visualization included “atmospheric wind and temperature outputs, ADCIRC storm surge [data] and some aerial photography maps,” Venkataraman explained. The visualization that was presented at the conference can be found at: http://www.cct.lsu.edu/projects/sc05/index.php.
Six months later, the team finished another, more detailed information sequence. The data in the March 2006 visualization includes that of the early visualization, as well as satellite images and elevation maps. Although it was no easy task for the team to coordinate time and position in space for all of this information, they put in the time and effort to make the visualization as accurate as possible.
Although each separate piece of data is not particularly innovative, scientists have never before seen the data presented together in a composite 3D visualization. With this information, they can see how everything works together. This is a giant step toward better understanding hurricanes and the forces behind them. As Stephen Beck, producer of the visualization explained, “We’re trying to give a sense of the inside of the storm.”
The Visualization Team
The Katrina visualization was created at the Lab for Creative Arts and Technologies (LCAT), a division of CCT, by a team of four people from four very different backgrounds. According to Brygg Ulmer, an assistant professor who works at CCT and whose hardware devices help to steer the visualization, “one of CCT’s major roles is to bring together different people with diverse skills.” The team includes faculty member Beck, staff members Benger and Venkataraman, and graduate student Amanda Long.
Beck serves as professor of composition and computer music at the LSU School of Music. He is also the head of LCAT, which brings together science and the arts.
Benger, who is from Germany, where he worked for eight years, joined LSU in September of 2005. His specialty is in exploring and developing techniques for visualizing scientific data.
Venkataraman has expertise in advanced visualization algorithms that maximize the performance of graphics hardware.
Long joined the team in January 2006 and works on the animation, color maps, the narrative, and video editing.
“I was pretty impressed that they wanted me,” Long said. “They gave me a pretty big role [in the project]. It’s inspiring when you collaborate with professionals. These people have amazing backgrounds. It was nice to be valued for having a different background, having come from fine arts.”
Continuing the Vision
Although CCT has accomplished much in terms of hurricane simulations, their work is far from over.
“With each step of refining the visualizations, more details become visible, and with our current methods we do require consistent data to make meaningful visualizations,” explained Benger. According to Beck, “We’re working to help evolve the science.”
The team has several goals:
- To include more hurricane data in the visualization
- To better synchronize the data that they have in order to form a picture that is as accurate as possible
- To build a workflow that can render a visualization that can be seen in a matter of hours rather than a matter of months
Another important aspect of the project is that the visualization program can be the foundation for making hurricane simulations. Hypothetical information can be inputted to “create” a hurricane; this is important for studying and predicting hurricanes. According to Venkataraman, “The goal of this project is … to aid in disaster forecasting, awareness, and management.”
The ability to accurately make hurricane predictions is especially important for the LSU Hurricane Center.
“Our focus is on forecasting. Our big problem is trying to get the forecast out as quickly as possible, said Associate Professor Paul Kemp, who works at the Hurricane Center. “Our main purpose is to educate people about the dangers of storms. Anything that makes the storm threat more real to people is beneficial.
Sandra Stepongzi | Mass Communication
| student writer
LSU Office of Public Affairs
Spring 2006
