AERMOD, the preferred model of the U.S. EPA for near-field air dispersion modeling, requires the use of two meteorological files: the surface (.SFC) and profile (.PFL) files.
Generating and Using Meteorological Data in AERMOD
1. Prepared by:
BREEZE Software
12770 Merit Drive | Suite 900 | Dallas, TX 75251
+1 (972) 661-8881 | breeze-software.com
George J. Schewe, CCM, QEP
June 26, 2012
Generating and Using
Meteorological Data in AERMOD
2. M t l i T t tiMeteorology in Transportation
Hot Spot ModelingHot Spot Modeling
AERMOD mentioned
i S ti 3 6in Section 3.6
Focus here on
AERMOD input filesAERMOD input files
Section 7.5 -
Incorporating
Meteorological Data
From where do the
data come?data come?
3. Wh t i AERMOD?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
4.
5. H t S t M d li PHot-Spot 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
sourcessou ces
5. Select AQ model, meteorology, roadway configurations,
receptors, background concentrations
6 C l l t d i l t NAAQS d6. Calculate design values, compare to NAAQS, and
determine conformity
7. Consider mitigation or control measures and repeat
6.
7. Meteorological Data for AERMOD
Finding representative meteorological
d t NWS FAA SCRAM itdata – NWS, FAA, SCRAM, onsite
Surface and upper air data
AERSURFACE for albedo, Bowen
ratio, surface roughness
AERMET preprocessor
8. S l ti M t l fSelecting Meteorology for
Project-Level Hot-Spot AnalysisProject Level Hot Spot Analysis
Surface met data – NWS, Onsite, other
Offsite met data – minimum five years
Onsite met data – minimum one year
U i t d t Upper air met data
Surface characteristics, land use
Population data – used for urban-rural
Representative of the project area?
9. R t ti fRepresentativeness of
Meteorology for Hot-Spot AnalysisMeteorology 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 Similarity of terrain features
Climate similarities
11. S f D tSurface Data
National Weather Service Data is typical
TD-3505 format (Integrated Hourly Surface 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-oneminftp://ftp.ncdc.noaa.gov/pub/data/asos-onemin
Verify station location at
http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?WWDI~StnSrch
12. htt // i d / / d /http://gis.ncdc.noaa.gov/map/cdo/
13. htt // i d / / dhttp://gis.ncdc.noaa.gov/map/cd
o/o/
16. U Ai D tUpper Air Data
National Weather Service Data is typical
FSL Format (Forecast Systems Laboratory) 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
18. Upper Air Station LocationUpper Air Station Location
BiGoogle Earth Bing
19. L d ULand Use
From the USGS Seamless Server at
http://seamless.usgs.gov/website/seamless/viewer.htm
Currently only NLCD92 format
20. R i f L d UReview of Land Use
Facility Landuse
21. AERSURFACE O t tAERSURFACE Output
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
Alb – albedo is the
amount of solar radiation
reflected by the surface
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
Bo – Bowen ratio is the
ratio of sensible to latent
heat_
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
Zo – surface roughness
length is related to the
land use which interrupts
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
land use which interrupts
smooth-flowing winds at
the surface
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
22. AERMET P iAERMET Processing
Stage 1 and 2
Raw Sounding
File
AERMET QA
-------------- Stage 1 and 2 -----------------
Stage 3
Surface
Raw
S f Fil
AERMET QA
File
MERGE
Surface File
AERMET QA
Raw
MERGE
Upper
Manual/AERMET
On-site File
Explicit Land
Bowen ratio,
roughness,
QA
1-min data AERMINUTE
Explicit Land
Use Analysis
g ,
albedo
23. F t f AERMETFeatures of AERMET
Processes one minute and hourly surface observations,
twice-daily upper air soundings, and on-site
measurements:
AERMINUTE processes one minute u and AERMINUTE – processes one minute u and
AERMET – processes in three stages
Stage 1: Extracts/processes data from AERMINUTE,S age ac s/p ocesses da a o U ,
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
b d l t f b AERMODboundary layer parameters for use by AERMOD
24. Surface Turbulence Parameters
AERMET computes turbulence parameters
for use in AERMOD
Sensible heat flux
Surface friction velocity
Convective velocity scale Convective velocity scale
Convective boundary layer height
Vertical potential temperature gradientp p g
Stable boundary layer height
Monin-Obukhov length
25. Processed Met DataProcessed Met Data
Met Data File using PCRAMMETMet Data File using PCRAMMET
Surface Met Data File using AERMET
26. Questions/Discussion?
George J. Schewe, CCM, QEP
(859) 341-8100(859) 341-8100
gschewe@trinityconsultants.com
www trinityconsultants comwww.trinityconsultants.com