USEPA/OAQPS Meteorologic

Modeling Analyses

Ad Hoc Met Modeling Meeting

July 30, 2002

Pat DolwickUSEPA: OAQPS/EMAD/AQMGNOAA: ARL/ASMD/APSB
Overview

 Importance of Meteorological M

 often-overlooked, relative to emissions/ increasingly important in PM/visibility

 Recent Meteorological Analyses 

 1996 continental U.S. MM5 data set (MC U.S./Canada modeling (July 1995 MM5)

 Present Meteorological Analyses 

 support upcoming regulatory actions improve overall quality of Federal/State

meteorological activities
Three-legged stool analogy

Emissions estimates Emissions estimates Meteorologic

Meteorologic

AQM: physics/chemistry AQM: physics/chemistry

Air Quality Model Air Quality Model
Three-legged stool analogy (the hidden 

AQ Model

Decision Maker
Importance of Meteorological Modeling 

(often overlooked)

 Case Study: EPA Technical Analy

 Emissions: develop/evaluate modeling t

significant contractor resources; dedicatw/in EMAD (EFIG)

 Air Quality Modeling: develop/evaluate 

tools; significant contractor resources; dgroup w/in EMAD (AQMG)

 Meteorology: limited & sporadic contrac

resources; extremely limited staff resou

 Tends to be rule rather than exc
Importance of Meteorological Modeling 

(increasing for PM/Vis)

 Migrating from ozone to 1-atmo

 Key parameters were generally well und

for local/regional ozone simulations. (PBUV, T)

 For PM/visibility, accurate representatio

humidity, clouds, and precipitation will bfor successful AQ model applications.
Importance of Meteorological Modeling 

(increasing for PM/Vis)
Importance of Meteorological Modeling 

(increasing for PM/Vis)
Importance of Meteorological 

Modeling (increasing for PM/V
Importance of Meteorological Modeling 

(increasing for PM/Vis)
Importance of Meteorological Modeling 

(increasing for PM/Vis)
Recent Meteorological Analyses @ USE

 Continental U.S. MM5 Applicatio

 MM5 v2.12, 108/36 km, 23 layers applied by MCNC MRF, K-F, simple ice, long & short-wave  resources did not permit diagnostic test model evaluation (low T, low PBL, wind used in Tier-2, Heavy-Duty Diesel, Clea data also sent to multiple other groups 

 (WRAP, TVA, Trinity Consulting, Ontario, AE
Recent Meteorological Analyses @ USE

 Eastern U.S. MM5 application: J

 MM5 v3.5, 108/36/12/04 km, 28 layers applied at EPA Blackadar, K-F, simple ice, surface radia schedule permitted only limited diagnos only qualitative model evaluation used in US/Canada annex modeling, pro

concept
Recent Meteorological Analyses @ USE

(July 1995, Eastern US)
Recent Meteorological Analyses @ USE

(July 1995, Eastern US)
Recent Meteorological Analyses @ USE

(July 1995, Eastern US)
Recent Meteorological Analyse

USEPA (July 1995, Eastern US

Developing Meteorological Input Data f

Quality Modeling Analyses

 Goal: development of high-quality, gridded meteorologic

that can be used to support urban, regional, and nationamodeling exercises over the United States.

 Alpine Geophysics is the primary contractor for the work 

with assistance from Atmospheric, Meteorological and EnTechnologies, LLC (ATMET)

 The work assignment consists of four major activities:

 Recommend meteorological model evaluation methodologie Investigate the utility of alternative meteorological data set Perform episodic, 12km MM5 simulation over the eastern U

2001)

 Perform an annual, continental U.S. MM5 simulation (2001) 
Annual Application of MM5 to the Cont

U.S.

 Goal: development of gridded meteorological datasets th

to support national air quality modeling

 A modeling protocol has been developed and is available

 Version 3.5 of MM5 Model to be run in 5-day intervals, with 12 hours of overlap  RPO grid projection (40°, -97° centroid; true latitudes of 33 34 vertical layers; surface layer 38 m Key model physics options (pending final determination): 

 Kain-Fritsch cumulus parameterization,  Blackadar PBL scheme,  Dudhia Simple Ice microphysics,  RRTM radiation scheme, and  the P-X land surface model (???).
Annual Application of MM5 to the Cont

U.S.

 The performance of the model will be assessed via an op

evaluation and a scientific evaluation:

 Operational: parameters will include winds, temperature, moisture, 

precipitation, etc.

 Operational: statistics will include bias, error, RMSE, index of agreem

of the mean values and standard deviations, skill scores, etc.

 Operational: evaluation will be conducted on national, RPO, and Sta

several time scales.

 Scientific: several diagnostic tests have been identified to provide ad

into model performance (i.e., assess the sensitivity of the results to options).

 Several diagnostic/sensitivity tests have been completed 

done for two 20-day episodes in February and July)

 use of larger domain with NNRP initialization data; use of “ZFAC” m

double FDDA; alternative land surface models; alternative microphy(Reisner).