Adequacy of Current Met Observations for Adequacy of Current Met Observations for Urban Dispersion ModelingUrban Dispersion Modeling

Challenges in Urban MeteorologyChallenges in Urban MeteorologyPanel 3Panel 3

September 21, 2004September 21, 2004

Mr. Richard FryMr. Richard FryDTRA, Consequence Assessment BranchDTRA, Consequence Assessment Branch

Making the World Safer

Observations – Surface

• WMO Reporting stations or opportunity• Hourly observations (WMO) or opportunity• Relatively dense network (over land)

Making the World Safer

Observations – Upper Air• WMO RAOB stations or opportunity• 12-Hourly observations (WMO) or temporal opportunity• Relatively coarse network• Urban Soundings almost non-existent

Moisture Temp Wind

Surface

Making the World Safer

Global and Mesonet Coverage

MesoWest Western US MesoWest Western US MesonetMesonet

WeatherFlow WeatherFlow US Coastal US Coastal

MesonetMesonet

•Standard WMO surface and upper air observations

•High resolution networks over limited geographic regions

•Provide enhanced detail in regions of complex coastline and/or terrain

Global Obs

Making the World Safer

VDRAS and VLASFuture Capability

Wash.D.C.

Release height – 10m1 kg inert, nonbuoyant gas15 June 1998

16:00 LT release

16:30 LT release

Doppler radar

Doppler lidar

Regional scale (1km res)

Neighborhood scale (75m res)

Making the World Safer

Summary

• Current Observation Systems of Limited Utility

• Observations within Urban Canopy not useful for Urban Dispersion Models

• Upper Air Soundings (SODAR, RAOB) and 4-D Data Assimilation (VLAS, VDRAS) show promise