Partners from academia and the public and private sector are joining NCAR in the effort, sponsored by the Defense Advanced Research Projects Agency (DARPA). NCAR brings to the test years of experience in developing systems that detect and warn for wind shear and turbulence at airports and protect against terrorism at high-profile events, such as the Olympic Games.
"Knowing how to properly respond to an attack or a toxic industrial incident requires the best modeling tools and sensors available today, and these must all work in a coordinated fashion in real time," says NCAR project leader Scott Swerdlin.
Understanding air circulation around the Pentagon is a unique challenge, says Swerdlin. The air circulations are very complex because of the building's size and unusual geometry. Temperature inversions, especially at night, could allow an airborne hazard to spread below rooftop height, which adds to the complexity of a monitoring system.
To tackle the problem, NCAR and partners built a nest of concentric computer models--each with a different strength--that predict weather conditions from the entire Washington region inward to the Pentagon itself. Information is routed among them every 15 minutes.
"The weather modeling system tested here is one of the most complex ever constructed," says NCAR's Thomas Warner, lead scientist on the project.
DARPA program manager Paul Benda adds, "The weather modeling system being tested will greatly improve our understanding of how to best protect the occupants of the Pentagon from a chemical or biological attack."
This spring's testing
Tests will occur between April 15 and May 15. In addition to the system's standard equipment (below), these tests will include
The dates of the SF6 releases hinge on day-to-day weather conditions. Scientists are taking advantage of wind directions and speeds that allow SF6 to be tracked from a release point directly toward the Pentagon.
"It's a very challenging exercise," says Swerdlin. "We're calling on a lot of experienced players and advanced weather forecasting systems in order to precisely time the releases."
What's in the system
Most modern weather forecasts target areas the size of a county, not a single building. NCAR and colleagues are developing a unique, fine-scale weather monitoring and forecasting system. It includes
NCAR's portion of this research is nonclassified. NCAR's primary sponsor is the National Science Foundation. Opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of the National Science Foundation.