Meteorological Data Issues for Class II Increment Analysis

Modeling Domain For Class II Analysis and Meteorological Approach to the Analysis 1. Microscale - Individual Sources or Close Grouping of Sources Onsite data – Site Specific Analysis, 1 year of data Offsite data – Screening Analysis,, Multiple years of data Gaussian Models – up to 100km (50km + S.I.R.) 2. Mesoscale – Increment Consumption over large area, urban growth Onsite data – Site Specific Analysis, 1 year of data Offsite data – Screening Analysis, Multiple years of data Gaussian Models – up to 100km (50km + S.I.R.) Puff Models – 100s of km

Models and Meteorological Pre- Processors for Class II Analysis  ModelsMet Processors  SCREEN3 Met. internal to Model  ISCST3 MPRM, PCRAMMET  AERMOD AERMET  CALPUFF CALMET

MPRM and PCRAMMET - Input  Meteorological Input Parameters – Wind Speed, Wind Direction, Temperature, Opaque Cloud Cover, Ceiling Height, Upper Air Data, Precipitation Data  Data Formats - CD144 (surface data) Sampson (surface data support) TD5600 (upper air data) TD9689 (estimated mixing heights) TD3240 (hourly precipitation) On-site (site specific data)

MPRM and PCRAMMET - Output  Wind Speed  Wind Direction  Temperature  Stability Class  Urban Mixing Height  Rural Mixing Height

AERMET - Input  Meteorological Input Parameters – Multi-Level WS, WD, and Temperature, Opaque Cloud Cover, Ceiling Height, RH, Pressure, Surface Heat Flux, Friction Velocity, and Roughness Length, Delta- T, Solar Radiation, Upper Air Data  Data Formats - CD144, SCRAM, SAMPSON (surface data) TD 3280 (surface data t) TD6201 (upper air data) On-site (site specific data)

AERMET - Output  Boundary Layer File  sensible heat flux  surface friction velocity  convective velocity scale  potential temp. gradient above mixing height  convectively-driven mixing height  mechanically-driven mixing height  Monin-Obukhov length  surface roughness length  Bowen ratio  albedo  WS, WD, and anemometer. height  temperature and measurement height used  Profile File  Measurement height  WD, WS  Temperature  Standard Dev. of Lateral WD  Standard Dev. of Vertical WS

Meteorological Parameters Individual Issues

 Wind Speed Linear Relationship to Concentration Collection Height Terrain Channeling Surface Roughness  Wind Direction Persistency Collection Height Terrain Channeling Surface Roughness / Obstructions Range of Representation

Temperature Vertical Profile (Delta-T) Stability  Surface Roughness / Obstructions (sigma theta)

Mixing Height (ISC) Based on two observation Low mixing heights in early morning. Urban vs. Rural Determinations

Convective and Mechanical Mixing Heights (AERMOD) Data availability for calculations Sensitive to Surface Roughness Plume splitting (partial penetration) and transport above the mixing layer

Surface Roughness, Albedo, and Bowen Ratio NWS site are generally flat areas Use Met site or Source site Surface Characteristics How do you evaluate an areas Model sensitivity to parameters

General Issues Domain Size Straight Line Transport up to 100 km (model limited to 50 km) Generating meteorological parameters of domains extending out hundreds of kilometers – poor resolution Formulation of Equations and Algorithms /Transferring into Code Data Formats and Availability Obsolete Onsite Data Sets (Intro of AERMOD)

General Issues Available Resources to Collect Data and Perform Analysis Range of Representation – Horizontal and Vertical Surface Influences – Roughness, Obstructions, Terrain Effects, Albedo, Bowen Ratio Available Meteorological Parameters/Collection Rate / QA Cost – Purchasing, generating and collecting data

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