Generating and Using Meteorological Data in AERMOD June 26, 2012 Prepared by: George J. Schewe, CCM, QEP BREEZE Software 12770 Merit Drive Suite 900 Dallas, TX 75251 +1 (972) 661-8881 breeze-software.com
Meteorology in Transportation ti Hot Spot Modeling AERMOD mentioned in Section 3.6 Focus here on AERMOD input files Section 7.5 - Incorporating Meteorological Data From where do the data come?
What is AERMOD? A steady-state plume model that incorporates air dispersion based on planetary boundary layer turbulence structure and scaling concepts, including treatment of both surface and elevated sources, and both simple and complex terrain. Support Center for Regulatory Air Models - www.epa.gov/scram001/dispersion_prefrec.htm
Hot-Spot t Modeling Process 1. Determine need for analysis 2. Determine approach, models, data 3. Estimate on-road motor vehicle emissions 4. Estimate emissions from road dust, construction, other sources 5. Select AQ model, meteorology, roadway configurations, receptors, background concentrations 6. Calculate l design values, compare to NAAQS, and determine conformity 7. Consider mitigation or control measures and repeat
Meteorological Data for AERMOD Finding representative meteorological data NWS, FAA, SCRAM, onsite Surface and upper air data AERSURFACE for albedo, Bowen ratio, surface roughness AERMET preprocessor
Selecting Meteorology for Project-Level Hot-Spot Analysis Surface met data NWS, Onsite, other Offsite met data minimum five years Onsite met data minimum one year Upper air met data Surface characteristics, land use Population data used for urban-rural Representative of the project area?
Representativeness ti of Meteorology for Hot-Spot Analysis Proximity of project to met data site Similarity of land use and surface characteristics Time period of data Similarity of terrain features Climate similarities
Airport vs Site LULC
Surface Data National Weather Service Data is typical TD-3505 format (Integrated Hourly Surface Data) obtained from National Climatic Data Center in Asheville or ftp://ftp3.ncdc.noaa.gov/pub/data/noaa Minute data obtained from NOAA at ftp://ftp.ncdc.noaa.gov/pub/data/asos-onemin noaa Verify station location at http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwdi~stnsrch
http://gis.ncdc.noaa.gov/map/cdo/ / / d /
http://gis.ncdc.noaa.gov/map/cd / / d o/
Station ti Location
Station Location Google Earth Bing
Upper Air Data National Weather Service Data is typical FSL Format (Forecast Systems Laboratory) obtained from NOAA online at http://www.esrl.noaa.gov/raobs Verify station location at http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwdi~stnsrch
Upper Air Observation sites
Upper Air Station Location Google Earth Bing
Land Use From the USGS Seamless Server at http://seamless.usgs.gov/website/seamless/viewer.htm Currently only NLCD92 format
R i f L d U Review of Land Use Facility Landuse
AERSURFACE Output t Season Sect Alb Bo Zo SITE_CHAR 1 1 0.17 0.92 0.026 SITE_CHAR 1 2 0.17 0.92 0.013 SITE_CHAR 1 3 0.17 0.92 0.012 SITE_CHAR 1 4 0.17 0.92 0.030 SITE_CHAR 1 5 0.17 0.92 0.021 SITE_CHAR 1 6 0.17 0.92 0.128 SITE_CHAR 1 7 0.17 0.92 0.571 SITE_CHAR 1 8 0.17 0.92 0.319 SITE_CHAR 1 9 0.17 0.92 0.285 SITE_CHAR 1 10 0.17 0.92 0.035 SITE_CHAR 1 11 0.17 0.92 0.018 SITE_CHAR 1 12 0.17 0.92 0.030 SITE_CHAR 2 1 0.16 0.66 0.036 SITE_CHAR 2 2 0.16 0.66 0.019 SITE_CHAR 2 3 0.16 0.66 0.017 SITE_CHAR 2 4 0.16 0.66 0.044 SITE_CHAR 2 5 0.16 0.66 0.031 SITE_CHAR 2 6 0.16 0.66 0.163 Alb albedo is the amount of solar radiation reflected by the surface Bo Bowen ratio is the ratio of sensible to latent heat Zo surface roughness length is related to the land use which interrupts smooth-flowing winds at the surface
AERMET Processing -------------- Stage 1 and 2 ----------------- Raw Sounding File AERMET QA Raw Surface File AERMET QA MERGE Raw Manual/AERMET On-site File QA Stage 3 Surface Upper 1-min data AERMINUTE Explicit Land Use Analysis Bowen ratio, roughness, albedo
Features of AERMET Processes one minute and hourly surface observations, twice-daily upper air soundings, and on-site measurements: AERMINUTE processes one minute u and AERMET processes in three stages Stage 1: Extracts/processes data a from AERMINUTE, archived data files and performs quality assessment (QA) Stage 2: Merges all data from Stage 1 and stores these data together in a single file Stage 3: Reads merged meteorological data and estimates boundary layer parameters for use by AERMOD
Surface Turbulence Parameters AERMET computes turbulence parameters for use in AERMOD Sensible heat flux Surface friction velocity Convective velocity scale Convective boundary layer height Vertical potential temperature gradient Stable boundary layer height Monin-Obukhov length
Processed Met Data Met Data File using PCRAMMET Surface Met Data File using AERMET
Questions/Discussion? George J. Schewe, CCM, QEP (859) 341-8100 gschewe@trinityconsultants.com www.trinityconsultants.com com