UNCLASSIFIED Initial Study of HPAC Modeled Dispersion Driven

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UNCLASSIFIED Initial Study of HPAC Modeled Dispersion Driven by MM 5 With and Without

UNCLASSIFIED Initial Study of HPAC Modeled Dispersion Driven by MM 5 With and Without Urban Canopy Parameterizations Dr. Chris Kiley – NGC Dr. Jason Ching - ARL, NOAA, RTP CDR Stephanie Hamilton - DTRA UNCLASSIFIED

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UNCLASSIFIED Outline of Presentation • • Overview of HPAC Objective of Study Preliminary Results

UNCLASSIFIED Outline of Presentation • • Overview of HPAC Objective of Study Preliminary Results Next Steps UNCLASSIFIED 3

UNCLASSIFIED DTRA • Defense Threat Reduction Agency • Mission is to safeguard the USA

UNCLASSIFIED DTRA • Defense Threat Reduction Agency • Mission is to safeguard the USA (and its allies) from weapons of mass destruction (WMD) (chemical, biological, radiological, nuclear, and high yield explosives) by providing capabilities to reduce, eliminate, or counter such threats and mitigate its effects. • DTRA’s Hazard Prediction and Assessment Capability (HPAC) • Automated software system provides the means to accurately predict the effects of hazardous material releases into the atmosphere and its impact on civilian and military populations. • The system models hazard areas produced by military or terrorist incidents and industrial accidents using: • integrated source terms • high-resolution weather forecasts • particulate transport analyses UNCLASSIFIED 4

UNCLASSIFIED Weather and Environment Data Input Process for HPAC Source Data Land Cover (Landscan)

UNCLASSIFIED Weather and Environment Data Input Process for HPAC Source Data Land Cover (Landscan) Terrain Data (Landscan) Weather Data (Many sources) Interpolation to Uniform Grid Transport & Dispersion Concentration in space and time Calculate Mass. Consistent Wind Field UNCLASSIFIED 5

UNCLASSIFIED Meteorological Input Considerations • Primary influence on Atmospheric Transport and Dispersion (ATD) •

UNCLASSIFIED Meteorological Input Considerations • Primary influence on Atmospheric Transport and Dispersion (ATD) • Compatible spatial resolution for the venue of the hazardous release • Operational: Rapid calculations • Is it Urban? This is the “Problem” we are to address. UNCLASSIFIED 6

UNCLASSIFIED Model Resolution Coarser resolution (5 km) reveals little detail in the wind field

UNCLASSIFIED Model Resolution Coarser resolution (5 km) reveals little detail in the wind field Higher resolution (1. 67 km) reveals additional wind field structure UNCLASSIFIED 7

UNCLASSIFIED Urban AT&D • Urban environment greatly affects local meteorology • Wind velocity and

UNCLASSIFIED Urban AT&D • Urban environment greatly affects local meteorology • Wind velocity and direction • Turbulence profiles • Thermal characteristics • NWP models not well suited to simulate urban areas • Grid resolutions, detailed building information, parameterization, operational timeliness of forecasts, etc. UNCLASSIFIED 8

UNCLASSIFIED Urban AT&D • Urban meteorology and AT&D is a current area of focused

UNCLASSIFIED Urban AT&D • Urban meteorology and AT&D is a current area of focused R&D • Not well understood yet highest probability of terrorist attack • NWP does not currently handle urban areas well • AT&D systems include simplified assumptions that describe the influence of urban environment • Mass consistent adjustments to underlying building topography • CFD solutions as computational capabilities advance • Coupled CFD/NWP models • Urban dispersion models UNCLASSIFIED 9

UNCLASSIFIED UDM and other approaches • Urban Dispersion Model (UDM) • Dstl (UK) •

UNCLASSIFIED UDM and other approaches • Urban Dispersion Model (UDM) • Dstl (UK) • Operationally Fast • Current Urban Capability within HPAC UNCLASSIFIED 10

UNCLASSIFIED Urban Dispersion Model (UDM) UNCLASSIFIED 11

UNCLASSIFIED Urban Dispersion Model (UDM) UNCLASSIFIED 11

UNCLASSIFIED UWM Winds @ 50 m Height Yellow arrows show wind speed and direction

UNCLASSIFIED UWM Winds @ 50 m Height Yellow arrows show wind speed and direction At 50 m above the ground, the flow is from the north or northeast at a steady speed UNCLASSIFIED 12

UNCLASSIFIED UWM Winds @ 7 m Height At 7 m above the ground, the

UNCLASSIFIED UWM Winds @ 7 m Height At 7 m above the ground, the flow is channeled around Capitol Hill and down the Mall, with strong winds Weaker winds in built-up parts of the city UNCLASSIFIED 13

UNCLASSIFIED Study Description HPAC now driven by modeled meteorology (MM 5): Sensitivity study to

UNCLASSIFIED Study Description HPAC now driven by modeled meteorology (MM 5): Sensitivity study to grid size and to urbanization with Reynolds Averaging vs detailed Urban Canopy Parameterization versions. Preliminary results for Houston include: • • 4 km MM 5 with UDM 1 km MM 5 Urban Canopy Model Date: August 29, 2000 Time of Release: 0700 EDT Duration of release: 4 hours UNCLASSIFIED 14

UNCLASSIFIED Houston Case Study • 12 UTC (7 AM) 29 August 2000 • GB

UNCLASSIFIED Houston Case Study • 12 UTC (7 AM) 29 August 2000 • GB Release, location arbitrarily chosen UNCLASSIFIED 15

UNCLASSIFIED 4 km UNCLASSIFIED 16

UNCLASSIFIED 4 km UNCLASSIFIED 16

UNCLASSIFIED 4 km with UDM UNCLASSIFIED 17

UNCLASSIFIED 4 km with UDM UNCLASSIFIED 17

UNCLASSIFIED 1 km UNCLASSIFIED 18

UNCLASSIFIED 1 km UNCLASSIFIED 18

UNCLASSIFIED 1 km with UDM UNCLASSIFIED 19

UNCLASSIFIED 1 km with UDM UNCLASSIFIED 19

UNCLASSIFIED 1 km Urbanized MM 5 UNCLASSIFIED 20

UNCLASSIFIED 1 km Urbanized MM 5 UNCLASSIFIED 20

UNCLASSIFIED Status of Study, Preliminary Findings & Caveats • • Successfully linked urbanized MM

UNCLASSIFIED Status of Study, Preliminary Findings & Caveats • • Successfully linked urbanized MM 5 with HPAC. Only limited results performed at this time UDM appears to slow spread as expected Relative reduction in agent spread due to enhanced grid resolution not evident for early morning release • Urbanized MM 5 comparative reduction in spread also not pronounced at 0700 • Results pending for different time of day release times UNCLASSIFIED 21

UNCLASSIFIED Future investigations continues to: • Examine and understand sensitivity to different times of

UNCLASSIFIED Future investigations continues to: • Examine and understand sensitivity to different times of release, different release locations and different duration of puff travel in order to appreciate differences in flow and turbulence fields due to grid size and urban descriptions. • Understand mesoscale modeling abilities to simulate effect of urbanization on land-lake/sea breeze, boundary layer and heat island structures on HPAC simulations. • Develop operational (fast) and R&D versions. UNCLASSIFIED 22

UNCLASSIFIED The End Thank you for your attention Disclaimer: The research presented here was

UNCLASSIFIED The End Thank you for your attention Disclaimer: The research presented here was performed under the Memorandum of Understanding between the U. S. Environmental Protection Agency (EPA) and the U. S. Department of Commerce's National Oceanic and Atmospheric Administration (NOAA) and under agreement number DW 13921548. This work constitutes a contribution to the NOAA Air Quality Program. Although it has been reviewed by EPA and NOAA and approved for publication, it does not necessarily reflect their policies or views. UNCLASSIFIED 23